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HomeMy WebLinkAboutReports - Drainage - 03/25/2025 FINAL DRAINAGE REPORT FOR POLESTAR VILLAGE Prepared For: POLESTAR GARDEN, INC PO BOX 211582 FORT COLLINS, COLORADO 80521 Michael Gornik (808) 443-9956 March 25t", 2025 Project No. 39797.01 Prepared By: JR Engineering, LLC 2900 South College Avenue, Suite 1 A Fort Collins, CO 80525 i ii TABLE OF CONTENTS TABLE OF CONTENTS.........................................................................................................................ii APPENDIX..................................................................................................................................... iii Engineer's Certification Block........................................................................................................... iii GENERAL DESCRIPTION AND LOCATION............................................................................................1 LOCATION .....................................................................................................................................1 DESCRIPTION OF PROPERTY ..........................................................................................................1 MASTER DRAINAGE BASIN DESCRIPTION.......................................................................................1 FLOODPLAIN SUBMITTAL REQUIREMENTS.....................................................................................2 DRAINAGE BASINS AND SUB-BASINS.................................................................................................2 MAJOR BASINS AND SUB-BASINS...................................................................................................2 EXISTING SUB-BASIN DESCRIPTION................................................................................................2 EXISTING OFFSITE DRAINAGE BASINS ............................................................................................3 EXISTING OFFSITE DRAINAGE DESCRIPTIONS.................................................................................3 PROPOSED SUB-BASINS DESCRIPTIONS .........................................................................................4 PROJECT DESCRIPTION......................................................................................................................9 PROJECT DESCRIPTION ..................................................................................................................9 PROPOSED DRAINAGE FACILITIES......................................................................................................9 GENERAL CONCEPT.......................................................................................................................9 WATER QUALITY/ DETENTION FACILITIES......................................................................................9 LOW IMPACT DEVELOPMENT......................................................................................................10 DRAINAGE DESIGN CRITERIA...........................................................................................................10 REGULATIONS.............................................................................................................................10 FOUR STEP PROCESS TO PROTECT RECEIVING WATERS ...............................................................10 DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS ...........................................................11 HYDROLOGIC CRITERIA................................................................................................................13 HYDRAULIC CRITERIA...................................................................................................................14 FLOODPLAIN REGULATIONS COMPLIANCE...................................................................................15 MODIFICATIONS OF CRITERIA......................................................................................................15 EROSION CONTROL.....................................................................................................................15 CONCLUSIONS.................................................................................................................................16 COMPLIANCE WITH STANDARDS.................................................................................................16 DRAINAGE CONCEPT...................................................................................................................16 REFERENCES....................................................................................................................................17 ii iii APPENDIX Appendix A—Figures Appendix B—Hydrologic Calculations Appendix C—Hydraulic Calculations Appendix D—Water Quality Calculations Appendix E—Reference Appendix F—Maps Appendix G—LID Exhibit Engineer's Certification Block I hereby attest that this report for the final drainage design for the Polestar Village was prepared by me or under my direct supervision, in accordance with the provisions of the Fort Collins Stormwater Criteria Manual. I understand that the City of Fort Collins does not and will not assume liability for drainage facilities designed by others. Joseph Martin Frank, PE Registered Professional Engineer State of Colorado No. 53399 iii I GENERAL DESCRIPTION AND LOCATION LOCATION The site is located in The Northwest Quarter of Section 16, Township 7 North, Range 69 West of the 6th P.M. in the City of Fort Collins, Larimer County, Colorado. More specifically, the site is a 20.77-acre property that is currently undeveloped. The site borders Mountaire Subdivision to the east, and to the south, the site borders the back of single-family residential lots facing West Elizabeth Ave. To the west, the site borders the Scenic Views retention pond and the Scenic Views Subdivision. To the north, the site borders single-family residential subdivisions, Locust Grove Filing No. 3, Locust Grove Filing No. 2, and the street Orchard Place. For additional information, refer to the site vicinity map within Appendix A of this report. DESCRIPTION OF PROPERTY The site generally drains west to east at a 2.5% to 1% slope. The site is located in the Canal Importation Basin, specifically north of West Elizabeth Street, east of South Overland Trail, and directly East of the Scenic Views Subdivision. The existing streets Orchard Place and West Plum Street dead end within the site. The Natural Resources Conservation Service (NRCS)soil survey shows that the majority are type C soils, which are characterized by a lower infiltration rate and corresponding higher runoff rates. The remaining soil on site are made up of Type B soils, which are characterized by a moderate infiltration rate and lower runoff rates. For additional information, refer to the NRCS soil map within Appendix A of this report. The existing site is currently used for Agricultural purposes and has an existing house,greenhouse, and field purposed for crops and areas with native grass. The existing irrigation ditch; i.e. the Pleasant Valley and Lake Canal is within the site, it borders the western boundary.The existing groundwater depths and boring locations are shown in Appendix E of this report. The depth from the bottom of the proposed pond to groundwater is approximately 6 feet, as shown in the Polestar Groundwater measurements spreadsheet in Appendix E of this report. MASTER DRAINAGE BASIN DESCRIPTION The site is located in the Canal Importation basin. The 2022 Canal Importation Basin — Selected Plan Update by Jacobs Engineering report specifies that the site is to have a regional detention facility. For additional information on the drainage patterns and characteristics of the site, refer to the Drainage Basins and Sub-Basins section of this report. 2 FLOODPLAIN SUBMITTAL REQUIREMENTS The site is on FEMA FIRM panel 08069C0960F, dated 12/19/2006, as shown in Appendix A. The site lies within FEMA Zone X, areas which are determined to be outside the 0.2% annual chance floodplain. The site is not located within a FEMA regulated floodplain, as shown in Appendix A in the FEMA attachments. The site is located in the City of Fort Collins Canal Importation floodway and floodplain, as shown in Appendix A in the City of Fort Collins Flood map. JR Engineering has prepared a CLOMR for the Polestar site. Once the grading on the site is completed,a LOMR will be submitted to verify the site is in compliance with the CLOMR. No building permits for the residential structures in the existing effective floodway will be issued until the LOMR is approved. The finished floor elevations near the Rain Garden and Scenic Views Pond are currently 1.5 feet above the base floodplain elevation, while the finished floor elevations for the homes and lots adjacent to the Polestar Detention Facility are at least 1.5 feet above the base floodplain elevation. These areas incorporate essential features, including HVAC and electrical equipment,which must all be elevated above the Required Flood Protection Elevation (RFPE). These elevations comply with Chapter 10 of the City Code, ensuring adherence to floodplain regulations such as flood proofing, floodway regulation, erosion buffer zone regulation, and no-rise certification. Additionally, the Conditional Letter of Map Revision (CLOMR) has been submitted,and the floodplain use permit will be submitted prior to the overlot grading, further securing compliance and safety against potential flood events. DRAINAGE BASINS AND SUB-BASINS MAJOR BASINS AND SUB-BASINS The Polestar Village site is 20.78 Acres; the site will be developed into a single-family, multi-family residential community with a community center and other amenities. The site will include future regional onsite and offsite detention. The site is located in the Canal Importation basin. EXISTING SUB-BASIN DESCRIPTION There are offsite areas that flow across the proposed development site.The existing drainage basins within the site flow from west to east. The existing corrected effective basin map is shown in Appendix E of this report. 3 Basin EP 21.5, acres and 3.1% impervious. This basin is composed of native grassland and an existing shed and includes a small portion of residential lots from Locust Grove that drains directly onto the site and drains to a swale towards West Plum Street. EXISTING OFFSITE DRAINAGE BASINS Currently, the site collects offsite runoff at two different locations. The site is currently in the overflow path of the Scenic Views retention pond and receives direct runoff from Locust Grove Filing No. 3; which enters the site via curb and gutter from Locust Grove Drive. The Scenic Views retention facility receives overflow runoff from the Pleasant Valley and Lake Canal, runoff from the Scenic Views multi-family Subdivision, the Colorado State Equine Horse Center, and the Center of Disease Control facility. For additional information, refer to the existing drainage basin SWMM map done in the hydrology portion of the CLOMR in Appendix E of this report. EXISTING OFFSITE DRAINAGE DESCRIPTIONS The offsite flows are currently routed through the site. The existing offsite basins have been modeled in the Canal Importation Basin Selected Plan Update Conceptual Design Report —Plum Channel Flow Path by Jacobs Engineering Group; Dated June, 2022 and within the Canal Importation Basin Hydrologic Conversion from MODSWMM to EPA SWMM 5.1; Anderson Consulting Engineers, Inc., December 6, 2013, (Revised July 3rd 2014). JR Engineering has revised some of the basins in section 5.0 of the CLOMR to account for Polestar site. The basin map for the offsite areas is shown within the corrected effective SWMM drainage map within Appendix E for the revised hydrology update within the CLOMR. Basin 13 is 2.9 acres and 10% impervious. This basin is directly tributary to the privately owned Scenic Views retention facility. The Scenic Views Pond was designed by JR Engineering, LTD to be a temporary retention facility in 1998 as shown in Appendix E of this report. The temporary retention facility has not yet been converted into a detention facility. The retention pond is pumped into the Pleasant Valley and Lake Canal via the existing submersible sumps pump, as shown in Appendix E of this report. The main pump has to be manually started, so the pond was modeled as a complete retention pond with no outflow, just an overflow path within the existing SWMM model. From the 1998 Scenic Views report, the manually operated pump system is designed to evacuate the pond within 24 hours after a large rainstorm event. Since this pond is a retention pond, without a gravity outfall the City does not model any volume below the spillway (the gravity outfall). This offsite basin is shown in the existing SWMM map shown within Appendix E of this report. 4 17W is 10.2 Acres and 45% impervious. This offsite basin is shown in the existing SWMM map, as shown within Appendix F of this report. For SWMM master planning purposes, Anderson used 45% impervious for single-family detached residential homes. This basin drains from Locust Grove Drive onto the Polestar site. Basin 10, 64.4 Acres, and 20% impervious. This basin is tributary to the Colorado State University Equine Reproduction Laboratory, located west of the site directly west of South Overland Trail. Runoff from this basin is released from the Equine Center pond and is then piped to the Scenic Views pond. This offsite basin is shown in the existing SWMM map shown within Appendix F of this report. Basin 11, 23.1 Acres and 70% impervious. This basin is tributary to the Scenic View's subdivision. Runoff from this basin is detained in the Scenic Views pond. This offsite basin is shown in the existing SWMM map shown within Appendix E of this report. PROPOSED SUB-BASINS DESCRIPTIONS To model the proposed runoff going into the on-site detention facility the pond was modeled as a composite 21.5-acre basin in SWMM a with 50% impervious value. The Polestar SWMM model was slightly more conservative than the basin area and impervious values to account for potential site changes and design variations through the CLOMR process, and the basin was delineated over a small portion of the Locust Grove subdivision that accounts for additional area. The proposed net area of the site is 20.77 acres at 47.5% impervious. The following is a description of the individual sub-basins for the onsite composite basin. The drainage sub-basin basins have been broken up and delineated, the onsite runoff is being routed with the rational method. The proposed site and pond drainage was modeled in a composite basin within SWMM, as part of the revised hydrology section of the CLOMR. Basin Al, 1.02 acres and 15.8% impervious this basin is composed of open space a proposed walk, a rain garden, and an overflow structure that treats runoff and water quality from the Polestar Village site. Basin A2, 0.58 acres and 51.6% impervious this basin is composed of multi-family residential units, a 24' wide private alley- Hoku Lane,and onsite parking.The runoff from this basin will be conveyed via a paned alley to the curb and gutter on West Plum Street. 5 Basin A3, 0.78 acres and 25.3% impervious this basin is composed of multi-family residential units, duplex units, a private walk and a swale. The runoff from this basin will be conveyed via a swale and chase to West Plum Street at dp 3a. Basin A4, 1.23 acres and 65.0% impervious this basin is composed of multi-family residential units, paved walk and paved driveways, paved parking spaces, a portion of the mitigated wetland and a 24' wide private alley Ohana Circle . The runoff from this basin goes to design point 4a and drains to W. Plum Street. Basin A5, 0.42 acres and 56.5% impervious this basin is composed of a courtyard, paved walks, duplex and multi-family units. The runoff drains to multiple area inlets. The runoff is then piped within the proposed storm sewer system in West Plum Street. Basin A6, 1.03 acres and 56.5% impervious this basin is composed of a local street West Plum Street, paved walk and front-facing multi-family units. The runoff from this basin goes to a sump inlet at design point 6a. Basin AT 0.85 acres and 60.5% impervious this basin is composed of a local Street West Plum, paved walk. The runoff from this basin goes to a sump inlet at design point 7a. Basin A8, 0.58 acres and 83.8% impervious, composed of the mixed-used community building, the northern portion of the temple, community, bed and breakfast building, the wellness center, a duplex, multi-family units, pedestrian walks, and a 24' wide private alley Ohana Circle. Runoff from this basin drains to W. Plum Street at dp 5d. Basin A9.1, 0.16 acres and 84.4% impervious, this basin is composed of the mixed used community building and a multi-family unit. Runoff from this basin will be captured via a series of on-grade inlets at dp 9a and piped to the proposed storm sewer in W. Plum St. Basin A9.2, 0.03 acres and 54.5% impervious, this basin is composed of open space, pedestrian walks and parts of the multi-family units drain to this basin. This basin drains to an area inlet at dp 9.2a,where runoff is then piped to the storm sewer in W. Plum St. 6 Basin A10, 0.09 acres and 84.7% impervious, is composed of the eastern portion of the temple, community, bed and breakfast building. Runoff from this building will drain into an area inlet at dp 10a, where it will then be piped to the proposed storm sewer system in W. Plum St. Basin A11, 0.13 acres and 68.8% impervious, this basin is composed of pedestrian walks, a portion of a multi-family unit, a gazebo. Runoff from this basin makes its way to an area inlet at dp 11a,where it is then piped to the proposed storm sewer system in W. Plum St. Basin Al2, 0.26 acres and 33.7% impervious this basin is composed of pedestrian walks a portion of the onsite playground and picnic area. Runoff from this basin makes its way to an area inlet where it is then piped to the proposed storm sewer system in W. Plum St. Basin A13, 0.40 acres and 61.0% impervious, this basin is made up a portion of the eastern half of the group home/ wellness center and the western portion of the temple, community, bed and breakfast building. Basin A15, 0.49 acres and 23.5% impervious, this basin is made up of pedestrian walks and a portion of the mitigated wetland. Runoff from this basin overtops the wetland and drains to an area inlet a dp 15a, where it is then piped to the proposed storm sewer system in W. Plum St. Basin A16, 0.13 acres and 51.1% impervious, this basin is made up of pedestrian walks, the pickle ball court, and drains to an area inlet at dp 16a. The runoff is then piped to the proposed storm sewer system in W. Plum St. Basin A17, 0.43 acres and 29.6% impervious, is made up of pedestrian walks, the community garden, and multi-family units. Runoff from this basin drains to a series of on-grade area inlets at dp 17a. The runoff from this basin is then piped to the proposed storm sewer system in W. Plum Street. Basin A18, 0.72 acres and 45.8% impervious, is made up of pedestrian walks, the community garden, the agriculture building, and multi-family units. Runoff from this basin is pipe via a series of on-grade inlets and a pipe with a trench drain at dp 18a due to the shallow slope of the swale. The runoff from this basin is then piped to the proposed storm system within W. Plum St. 7 Basin A19, 0.35 acres and 51.5% impervious is made up of pedestrian walks, the agriculture building, and a portion of the pickleball court. Runoff from this basin drains to a series of on-grade area inlets at dp 19a where it is then piped to the proposed storm sewer system in W. Plum St, Basin B1, 1.23 acres and 49.8% impervious, is made up of pedestrian walks, multi-family units, duplex units, a rain garden, and a 24' wide private alley - Mele Lane. Runoff of from this basin drains via a chase drain to a rain garden where it is treated for water quality. This the runoff from this basin goes to the onsite Polestar detention pond. Basin B2, 0.31 acres and 77.7% impervious, is made up of pedestrian walks, multi-family units, and a 24' wide private alley- Koku Lane. Runoff of from this basin drains via a chase drain to a rain garden where it is treated for water quality. This the runoff from this basin goes to the onsite Polestar detention Pond. Basin C1, 0.28 acres and 47.0% impervious this basin is composed of residential multi family units, paved walk, and a rain-garden. The runoff from this basin drains into a rain garden, where it is then released into the Polestar detention facility. Basin C2, 0.32 acres, and 30.5% impervious this basin is composed of paved walk, grass and the multi- family units. The runoff from this basin drains into an area inlet a design point 2C. Basin D1, 0.35 acres and 64.1% impervious this basin is composed a 24' wide paved private alley— Happy Heart Way, a duplex unit and paved walk. The runoff from this basin drains via the alley to a curb cut at 2d where it confluences with the runoff from Basin D2 and is treated for water quality. Basin D2, 0.22 acres and 62.9% impervious basin, is composed of a 24' wide paved private alley — Happy Heart Way, a duplex unit, and a paved walk. The runoff from this basin drains via the alley to a curb cut at 2d. Basin D3, 0.16 acres and 69.8% impervious this basin is this basin is composed a 24' wide paved private alley— Happy Heart Way, a duplex unit and paved walk. The runoff from this basin drains via the alley to a curb cut at 3d. From then the runoff is treated for water quality in a rain garden where it is then piped to the Polestar detention facility. 8 Basin D4, 0.25 acres and 60.9% impervious this basin is this basin is composed a 24' wide paved private alley— Happy Heart Way, a duplex unit and paved walk. The runoff from this basin drains via the alley to a curb cut at 4d. From then the runoff is treated for water quality in a rain garden where it is then piped to the Polestar detention facility. Basin D5, 0.29 acres and 67.3% impervious this basin is this basin is composed W. Plum Street, pedestrian walks and a portion of some multi-family units. The runoff from this basin drains to the rain garden via a chase a 5d. From then the runoff is treated for water quality in a rain garden where it is then piped to the Polestar detention facility. Basin D6, 0.28 acres and 60.5% impervious this basin is this basin is composed W. Plum Street. Runoff from this basin drain to a rain garden via a modified 5' type R inlet at dp 6d. From there on the runoff is then piped to the onsite Polestar detention pond. Basin D7, 0.11 acres and 85.5% impervious this basin is this basin is composed of a 24' wide private alley - Pono Way, and a duplex unit. Runoff from this basin drain to a rain garden via a curb cut at dp 7d. From there on the runoff is then treated within a rain garden and then it is pipe to the onsite Polestar detention pond. Basin D8, 0.18 acres, and 90.5% impervious this basin is composed of a 24'wide private—Pono Way, and pedestrian walks. Runoff from this basins drains via a curb cut at dp 8d. Basin E1 is 2.24 acres and 41.1% impervious. This basin consists of West Orchard Place and single-family residential units. The runoff from this basin will drain via a mid-block pan at dp le. Basin E2, 0.54 acres and 54.2% impervious this basin consists of a local residential road West Orchard Place, single family units and drains via curb and gutter to an on grade a mid block pan at dp 2e. Basin E3, 0.31 acres and 59.0% impervious this basin consists of a local residential road West Orchard Place, single family units and drains via curb and gutter to an on grade inlet a design point 3e. Basin F1, which is 3.9 acres and 31.6% impervious, is composed of the onsite detention facility. 9 OS1, 0.61 acres and 15.2% impervious this basin drains onto West Orchard Place, this basin is part of the back of lots of the Locust Grove subdivision. The runoff from this basin drains in the mid-block pan in West Orchard St and is released into the interim detention facility. OS2, 0.09 acres and 50.8% impervious, part of the Locust Grove Subdivision, this basin drains onto West Orchard Place and drains into the detention facility. PROJECT DESCRIPTION PROJECT DESCRIPTION Polestar Village is a residential multi-family development that will consist of a community center, wellness center, alleys, and local and collector roadways. The Polestar Village site will hold regional detention and water quality for the site. In the future, after the site is fully developed, the Canal Importation basin offsite improvements will be built with additional volume from the Jacobs Canal Importation basin Selected Plan updated June 2022. JR Engineering has designated approximately 3 acres of the site for regional detention. The proposed and future detention facility volume requirements were done by modeling the site in EPA SWMM as part of the revised hydrology portion of the CLOMR, as shown within Appendix E. The future onsite regional detention facility is shown in Appendix F of this report. PROPOSED DRAINAGE FACILITIES GENERAL CONCEPT The proposed improvements to the Polestar Village site will result in the developed condition being treated and detained for water quality. Low-impact development best management practices are proposed to improve the quality of runoff and aid in reducing peak flows. Specifically, rain gardens are proposed near the central portion of the site to treat and provide water quality for the majority of the development. Runoff from the site is captured in inlets located in the alleys and grate inlet along the curb and gutter. Runoff is conveyed in storm sewers, along curb and gutter, and via surface flow to rain gardens. Secondly, surface overflow paths will be provided, such that the 100-year storm flows remain at least 1.0 to 1.5 feet below the finished floor elevation. WATER QUALITY/ DETENTION FACILITIES The majority of the water quality is treated within the onsite rain gardens. The remaining water quality within the site will be treated in the water quality and detention facility. A small portion of the site of a 10 type A lot,will be left untreated due to the lot draining to the existing West Orchard R.O.W and pavement adjacent to the lot frontage. Additionally, a portion of the berm and access road to the detention pond will drain off-site and into the Plum Channel drainage way. This is not anticipated to have any negative impact on downstream drainage infrastructure, and the total water quality is being treated for 99% of the Polestar site's modified impervious area. For additional information, the LID water quality treatment exhibit is shown in Appendix G of this report. LOW IMPACT DEVELOPMENT A minimum of 75 percent of new impervious surface area is treated by a Low-Impact Development (LID) best management practice (BMP) in accordance with City criteria. An illustrative LID/ Surface Map is provided in Appendix G, and the sizing of the LID methods is provided in Appendix D. DRAINAGE DESIGN CRITERIA REGULATIONS This report was prepared to meet or exceed the City of Fort Collins stormwater criteria. The City of Fort Collins Stormwater Criteria Manual (dated 2018)(FCSCM) and the Urban Drainage Flood Control District's (UDFCD) Drainage Criteria Manual (USDCM)Volumes 1,2 and 3 were referenced as guidelines for this design. FOUR STEP PROCESS TO PROTECT RECEIVING WATERS The City of Fort Collins requires the Four Step Process to protect receiving waters.The four-step process incorporates reducing runoff volume, treating water quality capture volume, stabilizing streams, and implementing long-term source controls. Volume reduction is an important part of the Four Step Process and is fundamental to effective stormwater management. Per City Criteria, a minimum of 75 percent of new impervious surface area must be treated by a Low-Impact Development (LID) best management practice (BMP). The site incorporates rain gardens to provide water quality. The rain gardens will need to be cleaned and maintained to allow for long-term protection of the receiving waters. The proposed LID BMPs will have the effect of slowing runoff through the site lot and increasing infiltration and rainfall interception by encouraging infiltration and careful selection of vegetative cover. The improvements will decrease the runoff coefficient from the site and are expected to have no adverse impact on the timing, quantity, or quality of stormwater runoff. Overall, water quality will be improved by the development. The majority of the new impervious area is treated by the proposed raingarden in the northwestern 11 portion of the site as illustrated in the LID/Surface Map is provided in Appendix G. Refer to Appendix G for additional information on water quality treatment methods throughout the site. Step 1— Employ Runoff Reduction Practices All of the developed runoff through the site will be routed through the onsite interim Polestar detention pond. Step 2— Implement BMPS that Provide a Water Quality Capture Volume The Polestar site BMP treatment methods include bioretention basins (rain gardens),and WQCV provided within the interim Polestar detention pond. Step 3—Stabilize Drainageways The Interim Polestar detention facility provides flood control for the site. The runoff leaving the site will be channelized via a swale with a reinforced wall and a concrete pan with an energy dissipation forebay. In addition, a headwall is being built for the existing twin 24" RCP conduits to provide further stabilization to the existing drainage way. Step 4— Implement site-specific and other source-control BMPs To further enhance the stormwater management practices at the Polestar site, a dog waste station will be installed near the detention pond. This station will include waste bags and a disposal waste station, encouraging pet owners to clean up after their pets. DEVELOPMENT CRITERIA REFERENCE AND CONSTRAINTS The site is part of the Canal Importation - Basin Selected Plan Updates Alternatives Analysis Report, by Jacobs Engineering Group and is currently in the process of conceptual design. The site was previously analyzed in the Canal Importation Basin Hydrologic Conversion from MODSWMM to EPA SWMM 5.1; Anderson Consulting Engineers, Inc, December 6, 2013, (Revised July 3rd 2014). Jacobs Engineering group is currently modifying the Anderson model for the City of Fort Collins Capital Improvement plan for the Canal Importation basin. JR Engineering has evaluated the floodplain for the site, and JR Engineering has prepared a CLOMR to show that the improvements to the site are not within the floodplain.The CLOMR shows to the newly mapped floodway and floodplain, ultimately a LOMR will need to be approved to ensure the site complies with the CLOMR. The improvements for the planned regional Happy Hearts detention facility will take place in the future after the site is developed into Polestar Village. The Polestar Community will not impact the downstream development, and onsite detention will be provided within the site, but the homes downstream of the site will remain within the floodplain until the improvements 12 to the offsite and onsite facilities are put in place as recommended in the Canal Importation - Basin Selected Plan Updates, by Jacobs. The following items are a list of the subject improvements. • Conversion of Scenic Views retention pond to a detention pond. • Addition of a pipe outfall from the Scenic Views detention pond to the Happy Heart Farms, i.e., Polestar detention pond. • The volume of the onsite detention pond should be increased per the proposed outfall. • Construction of the planned outfall from the regional detention facility Currently, in the 100-year event, the Pleasant Valley and Lake Canal overflows and spills into the Scenic Views pond. The Scenic Views pond has a manually operated pumped outfall to the Pleasant Valley and Lake Canal. In the 100-year event, water overtops the Scenic Views pond and goes on the Polestar site, creating a floodplain as shown in the existing drainage map within Appendix F. In the proposed condition, the floodplain will go onto the onsite rain garden, overtop W. Plum Street and then the floodplain will be contained within the proposed detention facility. However, due to the shallow gravity outfall and limited volume the ultimate detention facility, as shown in Appendix E. - cannot be built due to the lack of a deep gravity outfall. The interim condition provides a drainage easement, an energy dissipation structure, and a concrete pan and will convey runoff, as shown in the Drainage Map in Appendix F. The onsite detention requirement for the site is the runoff difference between the 100-year developed inflow rate and the 2-year historic runoff is 4.88 Acre-ft. For additional information on the detention pond volume calculation, please refer to the referenced CLOMR provided hydrology portion provided in Appendix E. Jacobs calculated the ultimate volume (Happy Heart Detention Pond)within the Canal Importation- Basin Selected Plan Updates dated June 2022 as 8.3 Acre-ft. The total ultimate detention volume was calculated by adding the Happy Heart Detention pond of volume 8.3 Acre-ft with the required interim (onsite) detention volume 4.88 Acre-ft for the Polestar site for a total volume of 13.18 Acre-ft. JR Engineering has verified that the proposed pond layout can be graded in the future to detain over 13.18 Acre-ft as shown in the Future regional detention map provided in Appendix F. JR Engineering has prepared three SWMM models for the Polestar site within the City of Fort Collins Canal Importation Basin: the Corrected Effective Model, the Proposed Model, and the Ultimate Model. 13 The City of Fort Collins has requested that JR Engineering incorporate the Polestar Drainage model into the City master Canal Importation Drainage Plan SWMM mode. This was completed within the revised hydrology portion of the CLOMR, as shown within Appendix E. The groundwater for the site is greater than two feet below the Polestar detention pond invert, as noted in the CTL groundwater exhibit in Appendix E. HYDROLOGIC CRITERIA Weighted percent imperviousness were calculated for each basin using the Fort Collins Stormwater Criteria Manual Table 3.2-2 for each basin. EPA SWMM was used to model the runoff for the site and size the Polestar detention facility since the corresponding tributary area of the site is over 20 acres, and there are multiple detention basins upstream of the site that are in series with one another. The City of Fort Collins area has rainfall depths associated with the table below, as shown in Chapter 5 of the Fort Collins Stormwater Criteria Manual (FCSCM). Table 4.1A. IDF Table for SWMM Intensity Intensity Intensity Intensity Intensity Intensity Duration 2-year 5-year 10-year 25-year 50-year 100-year rain inthr indhr i nib r inlhr inlh inlhr 5 0.29 0.40 I1_49 0.63 0.79 1.00 10 0.33 0.45 0.56 0.72 0.90 1.14 15 0.38 0.53 0.65 0.84 1.05 1.33 20 0.64 0.89 1.09 1.41 1.77 2.23 25 0.81 1.13 1.39 1.80 2.25 2.84 30 1.57 2.19 2.0 3.48 4.36 5.49 35 2.85 3.97 4.87 6.30 7.90 9.95 40 1.18 1.64 2.02 2.61 3.27 4.12 45 0.71 0.99 1..21 1.57 1.97 2.48 50 0.42 0.58 0.71 0.92 1.16 1.45 55 0.35 0049 0.60 0.77 0.97 122_ 60 0.30 0.42 0.52 0.67 0.84 1.06 65 0.20 0.28 0.39 0.62 0.79 1.00 70 0.19 0.27 0.37 0.59 0.75 0.95 75 0.11B 0.25 0.35 0.56 0.72 0.91 s0 0.17 0.24 0.34 0.54 0.69 0_67 85 0.17 0.23 0.32 0.52 0.66 0.84 90 0.16 0.22 031 0.50 0.64 0.81 95 0.15 0.21 0.30 0.48 0.62 0.79 100 0.15 9.20 0.29 0.47 0.60 0.75 105 0.14 0.19 1 0.28 0.45 0.58 1 .73 110 0.14 0.19 0.27 0.44 0.56 0.71 115 0.13 0.18 0.26 0.42 0.54 0.69 120 0.13 0.18 0.26 0.41 0.53 0_67 14 The rational method was used to size the onsite storm sewer drainage facilities. Runoff coefficients from the FCSCM Table 3.2-1. Zoning Classification - Runoff Coefficients and Table 3.2-2. Surface Type - Runoff Coefficients were utilized to calculate the composite C values. Rainfall intensities for the 2 year minor storm and 100 year major storm were taken from table 3.4-1. IDF Table for Rational Method. HYDRAULIC CRITERIA StormCAD was utilized to determine the hydraulic capacity of the storm sewer system on site. Headloss coefficients were input as recommended by AMEC. "Modeling Hydraulic and Energy Sewer Gradients in Storm Sewers: A Comparison of Computational Methods." UDFCD, 6 Oct. 2009. The stormCAD V8i input/results are shown in Appendix C. A tailwater condition was used in the stormCAD model. The tailwater entered into the StormCAD model for the storm outfalls corresponds to the peak inflow within the pond for the 100-year event. This occurs 40 minutes into the model, and the depth of the pond is at 5105.98. No tail water was used for the 2-year model. For rain garden number 1, the water WQCV depth was used as the tailwater condition in the 100-year event. This corresponds to an elevation of 5107.35. For the outfall, a 100-year tailwater condition of 5106.23 was used to model the outfall into the floodplain located within the energy dissipation forebay. 5106.23 is the water surface elevation in the CLOMR at section 4673.7 —which is within in the energy dissipation directly downstream of the pipe. There is a mid-block pan that bi-sects West Orchard Place, that accepts runoff from Locust Grove. Runoff from the midblock pan drains into a swale in the 100 year event drains directly into the Polestar detention facility. The hydraulics of the mid-block plan and the swale were modeled within Flow Master as shown in Appendix C of this report. The 100-year spillway from the Scenic Views Pond and the Polestar Pond were sized during the CLOMR process in Flow Master. For additional information on the Spillway sizing, refer to the attached variance letter for the CLOMR in Appendix E of this Report. The inlets for the site were sized using parameters from the Fort Collins Stormwater Criteria Manual (FCSCM). The UD Inlet MHFD-Inlet, Version 5.03 (August, 2023) spreadsheet was utilized for the design and sizing of these inlets, as shown in Appendix C of this Report. 15 FLOODPLAIN REGULATIONS COMPLIANCE As previously stated, the site lies within FEMA Zone X, areas which are determined to be outside the 0.2% annual chance floodplain. The site is not located within a FEMA-regulated floodplain, as shown in Appendix A in the FEMA attachments. The site is located in the City of Fort Collins Floodplain and there is a floodway within the site, as shown in Appendix A in the City of Fort Collins Flood map. All development is within in compliance with Chapter 10 of the City of Fort Collins Code. MODIFICATIONS OF CRITERIA JR Engineering is proposing modifications for the spillway in Scenic Views Pond to increase emergency overflow capacity, decrease the overall breadth of the floodplain, and reduce the emergency overflow depth from 1.9 ft to 1.75 ft, as shown in the attached variance letter from the CLOMR in Appendix E. The proposed improvement will stop the spillway from overflowing by making it longer. In addition, the new proposed configuration will provide 6" of freeboard for the Scenic Views Spillway. The proposed Polestar/Happy Heart Farms Spillway is intended to prevent the flow from the emergency spillway from being directed towards existing structures and homes downstream. Both proposed spillways exceed the required depth of six inches, but the variance is necessary to achieve the desired outcomes. For additional information, refer to Appendix E for the variance letter, which was done with the CLOMR. The site will be broken up into five phases. For large-scale, multi-phase developments, the City of Fort Collins wants each phase to meet the 75% proposed LID treatment method. However, this requirement is not met until all phases of the development are complete. Instead of treating 75%of the site's impervious area in Phase 1, when the detention pond is constructed, the pond has been designed to treat offsite water quality from a portion of Locust Grove to the north. Currently, runoff from Locust Grove is left untreated. For additional information, the variance letter has been attached in Appendix E of this report. EROSION CONTROL The Polestar Utility Plans are in compliance with the Erosion Control Criteria established by the City of Fort Collins. The erosion control measures have been designed to minimize soil erosion and sediment transport off-site, ensuring compliance with local, state, and federal water quality regulations. All control measures will be maintained and inspected regularly to ensure their effectiveness throughout the construction process until final stabilization is achieved. All Erosion Control Materials and measures detailed in the Utility Plans adhere to the standards and specifications set forth by the City of Fort Collins within the Stormwater Criteria Manual. Erosion Control Plans, as referenced in the Polestar Utility Plans, 16 are living documents that can be subject to change under the direction of the Engineer of Record and/or the City of Fort Collins Engineering Department. CONCLUSIONS COMPLIANCE WITH STANDARDS The hydrologic and water quality calculations were performed using the required methods as outlined in the City of Fort Collins Stormwater Criteria Manual. The drainage plan and Stormwater management measures proposed within the Polestar site are complaint with all applicable State and Federal regulations governing Stormwater discharge. The drainage design conforms to the Jacobs' Master Canal Importation Basin plan by providing an area designed for detention in the ultimate gravity pond outfall configuration. The site conforms to the revised Hydrology of documented Polestar Floodplain Modeling Report by JR Engineering dated November of 2024. The floodplain compliance requirements for the site have been detailed in the CLOMR (Conditional Letter of Map Revision) for various parameters, including elevation, flood proofing, critical facilities, tie-in of upstream and downstream WSEL (Water Surface Elevation), and structures. DRAINAGE CONCEPT The proposed concept for the Polestar Village Development involves surface flows and piping of developed conditions and offsite flow through the interim detention facility. The site includes LID water quality facilities with rain gardens. Runoff for the site will be treated in an interim detention facility onsite. The proposed development will affect the drainageway termed "Plum Street Flow Path" which is located in the northwestern portion of the Canal Importation Basin. Onsite detention is provided for the Polestar site, but the homes downstream of the site will remain with the floodplain until the improvements to the offsite and onsite facilities are put in place as recommended in the Canal importation—Basin Selected Plan Updates Analysis Report, by Jacobs dated June 2022. 17 REFERENCES Fort Collins Stormwater Criteria Manual; City of Fort Collins, Colorado, December 2018. Urban Storm Drainage Criteria Manual (Volumes 1, 2,and 3); Urban Drainage and Flood Control District, June 2001. Canal Importation Basin Hydrologic Conversion from MODSWMM to EPA SWMM 5.1; Anderson Consulting Engineers, Inc, December 6, 2013, (Revised July 3rd 2014) Canal Importation basin Selected Plan Update, Jacobs Engineering Group, Dated June 2023 Preliminary Geotechnical Investigation Polestar Village; CTL Thompson, Dated November 2021 Floodplain Modeling Report for Polestar Village; JR Engineering, Dated November 2024 18 APPENDIX A - FIGURES W MULBERRY ST 1 � o I J I = I I H uiQ a > v ORCHARD PL co Z cl) W J J J > °' m O co Y W ELIZABETH ST I I I I ------- _-- \1 I I J i i I I 1 1 � I I W PROSPECT RD \ VICINITY MAP SCALE: 1"=1000' VICINITY MAP 1000 500 0 1000 2000 POLESTAR VILLAGE JOB NO. 3979701 ORIGINAL SCALE: 1" = 1000' 6-5-2022 SHEET 1 OF 1 A Westrian Company Centennial%3-740-M•Colorado�ft 719-593-M Fat Com 97&491-90•www7 ineeri Can 3 Hydrologic Soil Group—Larimer County Area,Colorado (V N m - O O 488700 48W 48W 489000 489100 489200 489300 489400 40°34'59"N 40°34'59"N m I - g i g �I 4' - 1 14N. fir• - `-? m� j �Y,Soil Map m"y not be vald'at this scare. m— ,� 40°34'23"N � � � T...na� � � _' 401 34'23"N 488700 488800 488900 489000 489100 489200 489300 489400 3 3 iv h Map Scale:1:5,390 fi printed on A portrait(8.5"x 11")sheet. o Meters N ° 0 50 100 200 300 Feet 0 250 500 1000 1500 Map projection:Web Mercator Comer coordinates:WGS84 Edge tics:UTM Zone 13N WGS84 USDA Natural Resources Web Soil Survey 5/17/2022 Conservation Service National Cooperative Soil Survey Page 1 of 4 Hydrologic Soil Group—Larimer County Area,Colorado MAP LEGEND MAP INFORMATION Area of Interest(AOI) 0 C The soil surveys that comprise your AOI were mapped at Area of Interest(AOI) 0 CID 1:24,000. Soils © D Warning:Soil Map may not be valid at this scale. Soil Rating Polygons A Not rated or not available Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil F—] AID Water Features line placement.The maps do not show the small areas of Streams and Canals contrasting soils that could have been shown at a more detailed 0 B scale. Transportation B/D *.. Rails Please rely on the bar scale on each map sheet for map 0 C measurements. � Interstate Highways 0 C/D US Routes Source of Map: Natural Resources Conservation Service Web Soil Survey URL: 0 D Major Roads Coordinate System: Web Mercator(EPSG:3857) 0 Not rated or not available Local Roads Maps from the Web Soil Survey are based on the Web Mercator Soil Rating Lines Background projection,which preserves direction and shape but distorts q distance and area.A projection that preserves area,such as the Aerial Photography Albers equal-area conic projection,should be used if more .-.. AID accurate calculations of distance or area are required. ++� B This product is generated from the USDA-NRCS certified data as ti B/D of the version date(s)listed below. C Soil Survey Area: Larimer County Area,Colorado Survey Area Data: Version 16,Sep 2,2021 r.i CID Soil map units are labeled(as space allows)for map scales ... D 1:50,000 or larger. Not rated or not available Date(s)aerial images were photographed: Aug 11,2018—Aug Soil Rating Points 12,2018 p A The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background E3 AID imagery displayed on these maps.As a result,some minor B shifting of map unit boundaries may be evident. B/D USDA Natural Resources Web Soil Survey 5/17/2022 Conservation Service National Cooperative Soil Survey Page 2 of 4 Hydrologic Soil Group—Larimer County Area,Colorado Hydrologic Soil Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 3 Altvan-Satanta loams,0 B 68.4 43.1% to 3 percent slopes 4 Altvan-Satanta loams,3 B 38.2 24.1% to 9 percent slopes 37 Fort Collins loam,5 to 9 C 0.0 0.0% percent slopes 48 Heldt clay loam,0 to 3 C 9.2 5.8% percent slopes 64 Loveland clay loam,0 to C 15.9 10.0% 1 percent slopes 74 Nunn clay loam, 1 to 3 C 2.2 1.4% percent slopes 76 Nunn clay loam,wet, 1 C 11.8 7.5% to 3 percent slopes 95 Satanta loam, 1 to 3 C 12.9 8.1% percent slopes Totals for Area of Interest 158.5 100.0% USDA Natural Resources Web Soil Survey 5/17/2022 Conservation Service National Cooperative Soil Survey Page 3 of 4 Hydrologic Soil Group—Larimer County Area,Colorado Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D)and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential)when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential)when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher USDA Natural Resources Web Soil Survey 5/17/2022 Conservation Service National Cooperative Soil Survey Page 4 of 4 'fir Al 4 lollRJL -?R MA pp F.�N �ARIlLllA; a , *�It -�HAD P — A tl f 41 mot lip 771 '* PLUM.ST p -V4j. , AL-1 1- 0 j VY EUIV ST - —. +W z i , AWANC '" �, ." ; i H k 61 City Flood Risk Map High Risk This information is based on the Federal Emergency Management City Floodway-Area of 100-year floodplain with greatest depths and Agency(FEMA)Flood Insurance Rate Map(FIRM)and the City of fastest velocities. Fort Collins Master Drainageway Plans. This letter does not imply that the referenced property will or will not be free from flooding or City Flood Fringe-May Include: damage. A property not in the Special Flood Hazard Area or in a Areas of FEMA 100-year floodplain(FEMA Zones A,AE,AO,and AH) City Designated Floodplain may be damaged by a flood greater Areas of City 100-year floodplain including ponding areas and sheet than that predicted on the map or from a local drainage problem flow areas with average depths of 1-3 feet. not shown on the map. This map does not create liability on the part of the City,or any officer or employee thereof,for any damage There is a 1%annual chance that these areas will be flooded. that results from reliance on this information. Moderate Risk All floodplain boundaries May include: are approximate. Areas of FEMA 500-year floodplain(FEMA Zone X-shaded). City of Areas of FEMA or City 100-year floodplain(sheet flow)with Fort Collins average depths of less than 1 foot. N `- Areas protected by levees from the 100-year flood. GIs Low Risk W Feet E 0 70 140 280 420 560 = Areas outside of FEMA and City mapped 100-year and 500-year floodplains.Local drainage problems may still exist. S Printed:07/14/2021 NOTES TO USERS 309000OFT FLOODING EFFECTS FROM 3095000FT ZONE AE 3100000 FT LEGEND ZONE AE CACHE LA POUDRE RIVER 1 50 11, 1-" JOINS PANEL 0743 (E c ° , (EL 5090) JOINS PANEL 0744 1050 0T 30" �, ,, INS map is for use in administering the National Flood insurance Program. it does 0 5 _ _ 0 8, ° �rECIAL FLOOD HAZARD AREAS(SFHAs)SUBJECT T O 1NUNDA—HON not necessarily identify all areas subject to flooding, particularly from local drainage 400 37'30" BY THE 1%ANNUAL CHANCE FLOOD sources of small size. The community map repository should be consulted for ZONE AE The 1%annual chance flood(100-year flood),also known as the base flood,is the flood that has a possible updated or additional flood hazard information. ZONE AE ZONE X (EL 5096) 4497000m N 1% chance of being equaled or exceeded in any given year. The Special Flood Hazard Area is the (EL 5098) area subject to flooding by the 1%annual chance flood. Areas of Special Flood Hazard include To obtain more detailed information in areas where Base Flood Elevations(BEES) 1470000FT Zones A,AE, AH,AO,AR,A99,V,and VE. The Base Flood Elevation is the water-surface elevation + N + of the 1%annual chance flood. and/or floodways have been determined,users are encouraged to consult the Flood a B� FLOODING EFFECTS FROM Profiles and FloodwayData and/or Summary of Stillwater Elevations tables contained p ZONE A No Base Flood Elevations determined. ry C CACHE LA POUDRE RIVER within the Flood Insurance Study(FIS) Report that accompanies this FIRM. Users ZONE X y92� ZONE AE Base Flood Elevations determined. should be aware that BFEs shown on the FIRM represent rounded whole-foot y� ZONE AH Flood depths of 1 to 3 feet(usually areas of ponding); Base Flood Elevations elevations. These BFEs are intended for flood insurance rating purposes only and o <<Q determined. should not be used as the sole source of flood elevation information. Accordingly, 0 09 ZONE AO Flood depths of 1 to 3 feet (usually sheet flow on sloping terrain); average flood elevation data presented in the FIS Report should be utilized in conjunction with depths determined.For areas of alluvial fan flooding,velocities also determined. the FIRM for purposes of construction and/or floodplain management. ZONE AR Special Flood Hazard Areas formerly protected from the 1%annual chance flood by a flood control system that was subsequently decertified. Zone AR indicates that the former flood control system is being restored to provide Boundaries of the floodwa s were comp uted at cross sections and inte olated y p rp 36 o rn protection from the 1%annual chance or greater flood. between cross sections. The floodways were based on hydraulic considerations with r` 31 ° regard to requirements of the National Flood Insurance Program. Floodway widths IY � ZONE A99 Area be protected from 1/°annual chance flood by a Federal flood protection and other pertinent floodway data are provided in the Floodway Data table shown on systemm under construction;no Base Flood Elevations determined. this FIRM. FLOODWAY AREAS IN ZONE AE The floodway is the channel of a stream plus any adjacent floodplain areas that must be kept free of Certain areas not in Special Flood Hazard Areas may be protected by flood control encroachment so that the 1%annual chance flood can be carried without substantial increases in structures. Refer to Section 2.4"Flood Protection Measures"of the Flood Insurance flood heights. Study Report for information on flood control structures for this jurisdiction. OTHER FLOOD AREAS Cm _4496000m N FEMA recommends that a Flood Insurance Policy be purchased for structures in z ZONE x Areas of 0.2%annual chance flood; areas of 1%annual chance flood with areas where levees are shown as providing protection from the 1% annual chance average depths of less than 1 foot or with drainage areas less than 1 square flood. Flooding is not covered by standard properly/fire/dwelling insurance policies nor 0 mile; and areas protected by levees from 1% annual chance flood. is it covered by Homeowners Insurance, Renters Insurance, Condominium Owners o Larimer County OTHER AREAS Insurance,or Commercial Property Insurance. Contact your insurance agent and local rN InUnincor Unincorporated Areas THIS AREA SHOWN AT A floodplain administrator for further information. p ZONE x Areas determined to be outside the 0.2%annual chance floodplain. 080101 m ZONE D Areas in which flood hazards are undetermined,but possible. Visit http://www.fema.gov/i)df/fhm/frm gsah.pdf for information on levees and the risk COUNTY ROAD 50 of flooding in areas shown as being protected by levees. T.8 N. SCALE OF 1 " — 500' o Floodplain boundary T.7 N. W Floodway boundary ON MAP NUMBER t) Z Zone D boundary The projection used in the preparation of this map was State Plane Colorado North ( a (feet). The horizontal datum was NAD 83,GRS80 spheroid.Differences in datum, spheroid, projection or UTM zones used in the production of FIRMS for adjacent 1465000FT + + 08069CO957 Z Boundary dividing Special Flood Hazard Area zones and jurisdictions may result in slight positional differences in map features across jurisdiction 0 f boundary dividing Special Flood Hazard Areas of different Base boundaries. These differences do not affect the accuracy of this FIRM. Flood Elevations,flood depths or flood velocities. —513 Base Flood Elevation line and value;elevation in feet* Flood elevations on this map are referenced to the North American Vertical Datum of Base Flood Elevation value where uniform within zone; 1988. These flood elevations must be compared to structure and ground elevations COUNTY ROAD 25G EL 987 elevation in feet* referenced to the same vertical datum. For information regarding conversion between the National Geodetic Vertical Datum of 1929 and the North American ALPACA TRAIL / *Referenced to the North American Vertical Datum of 1988 Vertical Datum of 1988, visit the National Geodetic Survey website at .449500 0m N A A Goss section line hftp://www.ngs.noaa.gov or contact the National Geodetic Survey at the following address: 104-50'37.5",39-30'00" Geographic coordinates referenced to the North American Spatial Reference System Division U, Datum of 1983(NAD 83),Western Hemisphere National Geodetic Survey,NOAA 3180000 FT 5000-foot ticks: Colorado State Plane coordinate Silver Spring Metro Center y system,North zone,Lambert Conformal 1315 East-West Highway RED RIDGE TRAIL 6 Conic projection Silver Spring,Maryland 20910 7 4276000'N 1000-meter Universal Transverse Mercator grid ticks,zone 13 (301)713-3191 1 v O KK6400 X National Geodetic Survey bench mark(see explanation in To obtain current elevation,description,and/or location information for bench marks Notes to Users section of this FIRM panel) shown on this map, please contact the Information Services Branch of the National Geodetic Survey at(301)713-3242,or visit its website at hftp://www.ngs.noaa.gov. COUNTY BIRCH DRIVE FLOOD INSURANCE RATE MAP LODGEPOLE PLACE ROAD 48C Base map information shown on this FIRM was provided by the Larimer County GIS MAP REPOSITORY and Mapping Department.Additional input was provided by the City of Fort Collins REDWOOD COURT Refer to listing of Map Repositories on Map Index Geographic Information Service Division.These data are current as of 2005. N o EFFECTIVE DATE OF COUNTYWIDE O The profile baselines depicted on this map represent the hydraulic modeling baselines DECEMBER E AT that match the flood profiles in the Flood Insurance Study report.As a result of improved 006 z ZONE A topographic data,the profile baseline, in some cases, may deviate significantly from D the channel centerline or appear outside the Special Flood Hazard Area. PECAN DRIVE �94000m N EFFECTIVE DATE(S)OF REVISION(S)TO THIS PANEL Corporate limits shown on this map are based on the best data available at the time of publication. Because changes due to annexations or de-annexations may have 146000OFT + occurred after this map was published, map users should contact appropriate BLUE SPRUCE DRIVE- community officials to verify current corporate limit locations. Please refer to the separately printed Map Index for an overview map of the s county showing the layout of map panels; community map repository addresses; RED CEDAR DRIVE x and a Listing of Communities table containing National Flood Insurance Program > q dates for each community as well as a listing of the panels on which each community �� fl is located. LO O lO W Contact the FEMA Map Service Center at 1-800-358-9616 for information W ..% O OC1 rn �:;, Q D on available products associated with this FIRM. Available products may include zr previously issued Letters of Map Change, a Flood Insurance Study Report, and/or d digital versions of this map. The FEMA Map Service Center may also be reached by n City of Fort Collins Fax at 1-800-358-9620 and its website at hftp://www.msc.fema.aov. z LAPORTE AVENUE O �' o COUNTY ROAD 46E QSQl Q2 For community map revision history prior to countywide mapping,refer to the Community ` G X w Map History table located in the Flood Insurance Study report for this jurisdiction. If you have questions about this map or questions concerning the National Flood r LL0512 J Lu Insurance Program in general, please call 1-877-FEMA MAP(1-877-336 2627)or 1 a 3 ;+ ¢ 9 To determine if flood insurance is available in this community,contact your insurance agent or call visit the FEMA website at hftp://www.fema.gov. 0 9 4493000m N the National Flood Insurance Program at 1-800-638-6620. 7 8 0 0 . z o G) £ > O Larimer County Vertical Datum Offset Table �" r`` 7 o = /`o�ll{yIutullV{lllr'�\' Vertical Datum Vertical Datum o Larimer County Flooding Source Offset(ft) Flooding Source Offset(ft) °° Unincorporated Areas City of Fort Collins Cache La Poudre River 3.0 ' + 4 Q$Q1Q1 ' MAP SCALE 1"=1000' �' 080102 Larimer County Soo o 1000 2000FEET jt p MULBERRY STREET(L _ Unincorporated Areas METERS 1455000FT + x1 �� + 080101 300 0 300 600 � � Example: To convert Cache La Poudre River elevations to NAVD 88,3.0 feet were added to the I NGVD 29 elevations. RAMPART ROAD PANEL 0960E Panel Location Map '' I �,, 4492000m N FIRM FLOOD INSURANCE RATE MAP LARIMER COUNTY, I7orsetdnth Reservoir 16 ark ELIZABETH STREET o ® COLORADO / _ 17 W AND INCORPORATED AREAS — z CATALPA PLACE Q 13 _ a 18 s J i _ CORN FLOWER DRIVE Z PANEL 960 OF 1420 ^y o t Z JO PLEASANT VALLEY ROAD Larimer Count O BLUE FLAX COURT BANYAN DRIVE (SEE MAP INDEX FOR FIRM PANEL LAYOUT) y ? O CONTAINS: lag CATALPA DRIVE r� Unincorporated Areas w ,� _ U 080101 ey :E u- C, a m COMMUNITY NUMBER PANEL SUFFIX x, Q } 4491 OOOm FORT COLLINS,CITY OF 080102 0960 F N 3x s � U City of Fort Collins v�oG LARIMER COUNTY 080101 0960 F 080102 �� PROSPECT ROAD + 1450000FT— ZONE X + 1 i§c DEN GOL CURRANT BOULEVARD Lu L SPRUCE DRIVE w C) 0 1 X ZONE A ' a ZONE X 120 1 Notice to User: The Map Number shown below should be used when placing map orders; the 24 19 Larimer County` _ — _ Community Number shown above should be This Digital Flood Insurance Rate Map(DFIRM)was produced ' used on insurance a lications for the subject through a Cooperating Technical Partner (CTP)agreement Unincorporated Areas a pp ) between the State of Colorado Water Conservation Board and 080101 community. the Federal Emergency Management Agency (FEMA). 400 33'45" 400 33'45" R coxs 1050 11' 15" JOINS PANEL 0970 JOINS PANEL 0967 105°07' 30" oti4Ai--�F� MAP NUMBER � 4 OOOm 4 OOOm 4 OOOm 4 OOOm 4 OOOm 1' � a 85 E 86 E 87 E 88 E 89 E ® o aP r� Additional Flood Hazard Information and � ��"' 08069C0960F Z. resources are available from local communities /t"w� and the Colorado water conservation Board. NOTE: MAP AREA SHOWN ON THIS PANEL IS LOCATED WITHIN TOWNSHIP 7 NORTH, RANGE 69 WEST,AND TOWNSHIP 8 NORTH, RANGE 70 WEST AND TOWNSHIP 7 NORTH, RANGE 70 WEST,TOWNSHIP 8 NORTH, RANGE 69 WEST. `~ 4` EFFECTIVE DATE ADD IS; DECEMBER 19, 2006 Federal Emergency Management Agency City of Fort Collins Utilities Fit Collins Floodplain Administration (970)416-2632 City of Fort Collins Floodplain Review Checklist Development Review Submittals Instructions: Complete this checklist by marking all boxes that have been adequately completed. Put an"NA"next to any items that are not applicable to this particular submittal. Any boxes that are left blank and do not have an"NA"marked next to them are considered incomplete. Date of Review: Reviewer's Name: Plat Man The following required items are on the plat: ❑ 100-year floodplain boundary ❑ City ❑ FEMA ❑ Floodway boundary ❑ City ❑ FEMA ❑ These items match the FIRM. (FEMA Basin) ❑ These items match the Master Plan. (City Basin) Site Plan The following required items are on the site plan: ❑ 100-year floodplain boundary- FEMA and City ❑ 500-year floodplain boundary(ifproposed structure is a"critical facility" and a 500-year floodplain is mapped) ❑ Floodway boundary ❑ Erosion buffer zones ❑ Restrictions related to use (ie. critical facility or no residential use of lower floor if floodproofed mixed use structure) Drainage and/or Grading Plan (or a separate Floodplain Sheet if it is too cluttered on Drainage and Grading Plan) The following required items are on the drainage and/or grading plan: ❑ 100-year floodplain boundary- FEMA and City ❑ 500-year floodplain boundary(ifproposed structure is a"critical facility" and a 500-year floodplain is mapped) ❑ Floodway boundary Page 1 of 7 City of Fort Collins Utilities Fit Collins Floodplain Administration (970)416-2632 ❑ Erosion buffer zones ❑ Cross-section locations ❑ BFE lines ❑ Lowest floor elevation of structures(bottom of basement or crawl space is considered the lowest floor) ❑ The floodplain and floodway boundaries are in the correct location and labeled properly. ❑ The cross-section and BFE lines are in the correct location and labeled properly. ❑ Elevations are referenced to the 1988 datum: ❑ Floodway regulations have been met. ❑ No fill in the floodway unless a hydraulic analysis shows "no-rise". ❑ No manufactured homes,except in an existing park,can be placed in the floodway. ❑ No changing a nonconforming non-residential or mixed use structure to a residential structure. ❑ Landscaping meets requirements for no encroachment in the floodway without a hydraulic analysis to show"no-rise". ❑ No storage of materials or equipment. ❑ A note is on the plans about the above floodway restrictions. ❑ Critical facilities regulations have been met: ❑ 100 year—no at-risk population, essential service, government service or hazardous material critical facilities ❑ 500 year Poudm—no at-risk population or essential service, critical facilities ❑ Any pedestrian bridges in the floodway that are not able to pass the 100-year flow are designed to be"break-away". ❑ Fences in the floodway will not block conveyance. Example: split-rail fence cabled together to not float, flap at bottom of privacy fence to allow water through (flap at BFE or above). ❑ Any items in the floodway that can float(Example: picnic tables,bike racks, etc.) are noted as being anchored. ❑ Erosion Buffer Zone requirements have been met: ❑ Design of any allowed development minimizes disturbance to channel bed and banks. Page 2 of 7 City of Fort Collins Utilities Fit Collins Floodplain Administration (970)416-2632 ❑ No structures allowed. ❑ No additions to existing structures allowed. ❑ Any fencing is split-rail design and break-away,but cabled.Must be oriented parallel to general flow direction. ❑ No detention or water quality ponds. ❑ No bike or pedestrian paths or trails except as required to cross streams or waterways. ❑ Road, bicycle and pedestrian bridges must span erosion buffer zone. ❑ No fill. ❑ No outdoor storage of non-residential materials or equipment. ❑ No driveways or parking areas. ❑ No irrigated vegetation and non-native trees, grasses, or shrubs. ❑ No utilities except as necessary to cross streams or waterways. ❑ No grading or excavation except as required for permitted activities in erosion buffer zone. ❑ No construction traffic except as required for permitted activities in erosion buffer zone. ❑ Any construction in the erosion buffer zone shows that it will not impact the channel stability. ❑ A note is on the plans about the above erosion buffer zone restrictions. ❑ Any necessary floodplain modeling has been submitted and approved. All modeling must follow the City's floodplain modeling guidelines. Special Poudre River Regulations ❑ Poudre River Floodway Regulations have been met. ❑ No construction ofnew residential,non-residential or mixed- use structures. ❑ No redevelopment of residential, non-residential or mixed-use structures. ❑ No additions to residential, non-residential or mixed-use structures. ❑ No fill unless hydraulic analysis shows "no-rise". ❑ Poudre River floodplain regulations have been met ❑ No construction of new residential or mixed-use structures ❑ No additions to residential structures ❑ No additions to mixed-use structures if there is an expansion in the residential-use area of the structure. ❑ No floatable materials on non-residential sites ❑ Emergency Response and Preparedness Plan(ERPP) draft has been prepared. Page 3 of 7 City of Fort Collins Utilities Fit Collins Floodplain Administration (970)416-2632 Information Related to Structures in the Floodplain ❑ For structures in the floodplain, a table is shown that lists the following: ❑ City BFE at upstream end of structure ❑ FEMA BFE at upstream end of structure (if different than City BFE) ❑ Regulatory flood protection elevation ❑ Lowest floor elevation(bottom ofbasement or crawl space is considered lowest floor) ❑ Floodproofing elevation for non-residential structures (if applicable) ❑ Garage slab elevation ❑ HVAC elevation ❑ The BFE at upstream end of structures are correct based on interpolation between the cross-sections. ❑ The regulatory flood protection elevation is correct. ❑ The lowest floor and HVAC are at or above the regulatory flood protection elevation. ❑ Elevations are referenced to the 1988 datum. ❑ A typical drawing detail is included for each foundation type proposed(slab-on- grade, basement, crawl space) showing the elevation of the HVAC and lowest floor elevation (which includes bottom of the basement or crawl space)relative to the BFE. ❑ If garage is not elevated to the regulatory flood protection elevation, then a drawing detail is included showing vent placement, size, and number. ❑ There is 1 square inch of venting for every 1 square foot of enclosed area. ❑ The bottom of the venting is not higher than 1 foot above grade. ❑ The venting is on at least two sides,preferably on upstream and downstream sides. (Does not have to be divided equally). ❑ If a non-residential structure is to be floodproofed, one of these conditions is met: ❑ All requirements on separate sheet titled"Floodproofing Guidelines" have been met. ❑ If floodproofing information is not submitted as part of the plans, then a note is on the plans stating that floodproofing information will be submitted at the time of the building permit application. ❑ For manufactured homes, all submittal requirements on separate sheet titled "Installation of a Mobile Home Located in a Floodplain: Submittal Requirements" have been met. Page 4 of 7 City of Fort Collins Utilities Fit Collins Floodplain Administration (970)416-2632 ❑ If the floodplain use permit is not going to be submitted until the building permit is applied for, then a note is on the plans stating that the floodplain use permit will be submitted at the time of building permit application. ❑ A note is on the plans stating that a FEMA elevation or floodproofing certificate will be completed and approved before the CO is issued. This is required even if property is only in a City floodplain. Drainage Report ❑ The site is described as being in the floodplain. Floodplain name and if the floodplain is a FEMA or City-designated is described. Any floodway or erosion buffer zones on the site are described. ❑ The FEMA FIRM panel # and date and/or the Master Plan information is cited. ❑ A copy of the FIRM panel with the site location marked is included in the report. ❑ If a floodplain modeling report has been submitted, that report is referenced. The reason for the floodplain modeling report is described. ❑ If a FEMA CLOMR or LOMR has been approved for the site, the case number is referenced. The reason for the CLOMR or LOMR is described. ❑ If a FEMA LOMR is required after construction, this is stated in the report. ❑ The location of the structures relative to the floodplain is described. If there is both a FEMA and a City floodplain on the site, the location of the structures relative to both is described. ❑ The use of the structures is described. This is to determine if the structure is residential, non-residential, or mixed-use. Also, structures in all 100-year and Poudre River 500-year floodplains cannot be used as a critical facility. (See Chapter 10 of City Code for definitions.) ❑ If in the Poudre River 100-year floodplain, the requirement to complete an Emergency Response and Preparedness Plan(ERPP) is discussed and the requirement for annual training drills and an annual update in the first quarter of every year is discussed. ❑ The report describes how the development is in compliance with the applicable floodplain regulation(Chapter 10 of City Code). (Examples: elevation of lowest floor above regulatory flood protection elevation, floodproofing, floodway regulation, erosion buffer zone regulation, no-rise, etc.) Page 5 of 7 City of Fort Collins Utilities Fit Collins Floodplain Administration (970)416-2632 ❑ The type of foundation construction for the structures (i.e. slab-on-grade, crawl space, basement, etc.) is discussed in the report. ❑ The type of foundation matches with the lowest floor elevations and grading plan. ❑ If any of the garages are not going to be elevated above the regulatory flood protection elevation, the hydraulic venting requirements are discussed. ❑ For structures in the floodplain, a table is included(same table as on the Drainage/Grading Plan)that lists the following: ❑ City BFE at upstream end of structure ❑ FEMA BFE at upstream end of structure (if different than City BFE) ❑ Regulatory flood protection elevation ❑ Lowest floor elevation(bottom ofbasement or crawl space is considered lowest floor) ❑ F000dproofing elevation for non-residential structures (if applicable) ❑ Garage slab elevation ❑ HVAC elevation ❑ Elevations are referenced to the NAVD 1988 datum. ❑ If the floodplain use permit is not going to be submitted until the building permit is applied for, then a note must be included in the report that states the permit will be submitted at the time of building permit application. ❑ If floodproofing information is not submitted as part of the plans, then a note must be in the report stating that floodproofing information will be submitted at the time of the building permit application. ❑ A note is in the report stating that a FEMA elevation or floodproofmg certificate will be completed and approved before the CO is issued. ❑ In the compliance section, Chapter 10 of City Code is listed. Floodplain Use Permit ❑ Floodplain Use Permit has been submitted for each structure. ❑ Permit fee has been submitted. ❑ All information on permit matches the plans. ❑ All information on permit meets floodplain regulations. Page 6 of 7 City of Fort Collins Utilities Fit Collins Floodplain Administration (970)416-2632 FEMA CLOMR AUproval ❑ FEMA has approved any necessary CLOMRs. ❑ The City has received copies of all updates to the FEMA submittal. Additional Comments: Floodplain terminology is defined in Chapter 10 of City Code. NOTE: Issues specific to individual sites may arise that result in additional requirements. These will be discussed during initial meetings with the applicant. Please refer to Chapter 10 of City Code for specific floodplain regulations. Page 7 of 7 19 APPENDIX B - HYDROLOGIC CALCULATIONS COMPOSITE%IMPERVIOUS CALCULATIONS Subdivision:Polestar Project Name: Polestar Location:Fort Collins Project No.:39797.01 Calculated By: ARJ Checked By: Date: 11/13/24 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Paved Roads and Walks Single Family Lots Roofs Landscaping/Lawns Basin ID Total Area(ac) %Imp. Area(ac) Weighted %Imp. Area(ac) Weighted %Imp. Area(ac) Weighted %Imp. Area(ac) Weighted% Basins Total Weighted%Imp.%Imp. %Imp. %Imp. Imp. Al 1.02 100% 0.03 2.9% 45% 0.12 5.4% 90% 0.07 6.0% 2% 0.80 1.6% 15.8% A2 0.58 100% 0.19 32.5% 45% 0.00 0.0% 90% 0.12 18.1% 2% 0.27 0.9% 51.6% A3 0.78 100% 0.08 10.0% 45% 0.00 0.0% 90% 0.12 13.9% 2% 0.58 1.5% 25.3% A4 1.23 100% 0.58 47.6% 45% 0.00 0.0% 90% 0.23 16.7% 2% 0.42 0.7% 65.0% A5 0.42 100% 0.06 14.7% 45% 0.00 0.0% 90% 0.19 41.1% 2% 0.17 0.8% 56.5% A6 1.03 100% 0.61 59.7% 45% 0.09 4.1% 90% 0.05 4.4% 2% 0.27 0.5% 68.7% A7 0.85 100% 0.48 57.2% 45% 0.01 0.5% 90% 0.05 4.9% 2% 0.31 0.7% 63.3% A8 0.58 100% 0.39 66.7% 45% 0.00 0.0% 90% 0.11 16.8% 2% 0.09 0.3% 83.8% A9.1 0.16 100% 0.05 32.2% 45% 0.00 0.0% 90% 0.09 52.0% 2% 0.02 0.2% 84.4% A9.2 0.03 100% 0.01 37.2% 45% 0.00 0.0% 90% 0.01 16.4% 2% 0.01 0.9% 54.5% A10 0.09 100% 0.02 25.8% 45% 0.00 0.0% 90% 0.06 58.7% 2% 0.01 0.2% 84.7% All 0.13 100% 0.04 34.7% 45% 0.00 0.0% 90% 0.05 33.6% 2% 0.04 0.6% 68.8% Al2 0.26 100% 0.06 21.7% 45% 0.00 0.0% 90% 0.03 10.7% 2% 0.17 1.3% 33.7% A13 0.40 100% 0.03 7.2% 45% 0.00 0.0% 90% 0.23 53.1% 2% 0.13 0.7% 61.0% A14 0.09 100% 0.00 0.0% 45% 0.00 0.0% 90% 0.02 19.6% 2% 0.07 1.6% 21.1% A15 0.49 100% 0.06 11.6% 45% 0.00 0.0% 90% 0.06 10.3% 2% 0.38 1.5% 23.5% A16 0.12 100% 0.06 50.1% 45% 0.00 0.0% 90% 0.00 0.0% 2% 0.06 1.0% 51.1% A17 0.43 100% 0.04 9.0% 45% 0.00 0.0% 90% 0.09 19.1% 2% 0.30 1.4% 29.6% A18 0.72 100% 0.17 24.3% 45% 0.00 0.0% 90% 0.16 20.4% 2% 0.38 1.1% 45.8% A19 0.35 100% 0.13 38.5% 45% 0.00 0.0% 90% 0.05 12.0% 2% 0.17 1.0% 51.5% 81 1.23 100% 0.32 25.6% 45% 0.00 0.0% 90% 0.32 23.3% 2% 0.60 1.0% 49.8% B2 0.31 100% 0.18 58.1% 45% 0.00 0.0% 90% 0.07 19.2% 2% 0.06 0.4% 77.7% Cl 0.28 100% 0.00 1.2% 45% 0.00 0.0% 90% 0.14 44.8% 2% 0.14 1.0% 47.0% C2 0.32 100% 0.02 6.2% 45% 0.00 0.0% 90% 0.08 23.0% 2% 0.22 1.4% 30.5% Dl 0.35 100% 0.20 55.9% 45% 0.00 0.0% 90% 0.03 7.5% 2% 0.13 0.7% 64.1% D2 0.22 100% 0.11 50.1% 45% 0.00 0.0% 90% 0.03 12.0% 2% 0.08 0.7% 62.9% D3 0.16 100% 0.09 53.2% 45% 0.00 0.0% 90% 0.03 16.1% 2% 0.05 0.6% 69.8% D4 0.25 100% 0.14 54.9% 45% 0.00 0.0% 90% 0.01 5.2% 2% 0.10 0.8% 60.9% D5 0.29 100% 0.15 51.3% 45% 0.00 0.0% 90% 0.05 15.3% 2% 0.09 0.6% 67.3% D6 0.28 100% 0.16 57.3% 45% 0.00 0.0% 90% 0.01 2.4% 2% 0.11 0.8% 60.5% D7 0.11 100% 0.07 66.1% 45% 0.00 0.0% 90% 0.02 19.1% 2% 0.01 0.3% 85.5% D8 0.19 100% 0.15 78.9% 45% 0.00 0.0% 90% 0.02 11.4% 2% 0.02 0.2% 90.5% El 2.24 100% 0.41 18.3% 45% 1.10 22.1% 90% 0.00 0.0% 2% 0.73 0.6% 41.1% E2 0.54 100% 0.19 34.6% 45% 0.23 19.1% 90% 0.00 0.0% 2% 0.12 0.5% 54.2% E3 0.31 100% 0.11 35.0% 45% 0.17 23.7% 90% 0.00 0.0% 2% 0.04 0.2% 59.0% Fl 3.92 100% 0.04 1.0% 45% 0.53 6.0% 90% 1.00 22.9% 2% 2.36 1.2% 31.2% Onsite Basins 20.77 47.5% OSl 0.61 100% 0.00 0.0% 45% 0.00 0.0% 90% 0.09 13.5% 2% 0.52 1.7% 15.2% OS2 0.IL 090.03 36.0% 45% 0.0% 90% 0.01 13.8% 2% 0.04 1.0% 50.8% Onsite Basins OS3 and OS2 21.47 46.6% 17W 1 10.20 45.0% X:V970000.e109N701\E.e10.v geV979701 Dreina Calcs_TemPlat Q.07A. Pagc I oft 1/10/2025 Table 4.1-3.Surface Type-Percent Impervious Percent Impervious Surface Type 11%) Hardscape or Hard Surface As halt,Concrete ion Rooftop 90 Recycled Asphalt so Gravel 40 Pavers 40 Landscape or Pervious Surface Playgrounds 25 Lawns,Sandy soil 2 Lawns,Clayey soil 2 X:V970000.e11\39N701\E.e10.regrV979701 D.i-W Calcs_Template_v2.07A. Prgr2of2 2/10/2025 COMPOSITE RUNOFF COEFFICIENT CALCULATIONS Subdivision:Polestar Project Name:Polestar Location:Fort Collins Project No,39797.01 Calculated By:AN Checked By: Date:11/13/24 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10-0 11.0 12.0 13.0 14.0 15.0 16.0 17.0 18.0 19.0 20-0 21.0 Paved Roads/Ashphalt77- Single Family Lutz7-71777 Roofs lawns Total Area lac) Hydrologk Basins Total Weightetl Basins Total Welghtetl Basin 10 ���ffidem Area lacl 2-YEAR[ 100-YEAR[ Runoff Coefflckm Area(ac) 2-YEARC 100-YEARC Runoff prea(ac) 2-YEAR[ 100-YEAR[ Runoff CaelBckrd Ares(ac) 2-YEARC 100-YEAR[ 2YEARC 100 YEARC SoilzGroup Ceemtk nt Al 1.02 C 0.95 0.03 0.03 0.03 0.55 0.12 0.07 0.08 0.95 0.07 0.06 ON 0.20 0.80 016 0.20 0.31 0.39 Al 0.58 C 0.95 0.19 0.31 US 0.55 0.. 1- 0.. 0.95 0.12 0.19 0.24 1.20 O.V 009 012 0.60 0.]4 A3 0.78 C 0.95 0.08 0.09 0.12 0.55 0.00 0.00 0.00 0.95 012 0.15 018 010 0.58 0.15 0.19 0.39 0.49 A4 1.23 C 0.95 0.58 0.45 0.56 0.55 ODO 0.00 ODO 0.95 013 0.. 0.. 0.20 0.42 0.07 008 0.70 1!17 AS 0.42 C 0.95 0.06 0.14 OA7 0.55 0.00 0.00 0.00 0.95 0.0 0.43 0.54 010 0.17 0.08 0.10 0.65 082 AS 1.03 C 0.95 0.61 0.57 0.71 0.55 0.09 005 0.06 0.95 0.05 ODS 0.0. 0.20 0.27 OAS 0.07 0.72 0.90 A7 0.95 C 0.95 0.48 0.54 0.0 0.55 0.01 0.01 0.01 0.95 0.05 0.05 0.06 0.20 0.31 0.07 0.09 0.0 084 AE 0.58 C 0.95 0.39 063 0.71 0.55 I= 0.00 0.W 0.95 0.11 0- 0.22 010 0.09 0.03 0.04 0.84 1.00 ASA 0.16 C 0.95 0.05 0.31 0.38 0.55 0.00 I= 0.00 0.95 0.09 0.55 0.69 0.20 0.02 0.02 0.03 0.8] 100 A9.2 0.03 C 0.95 0.01 0.35 0.44 0.55 0.00 0.00 O.W IAS 0.01 0.36 0.44 010 0.01 009 0.11. 0.80 1.00 AW 0.09 C 0.91 0.02 015 0.31 0.55 0.00 0.00 0.00 0.95 0.06 0.62 0.77 0.20 0.01 0.02 0.02 0.88 1.00 All 0.13 C 0.95 D.04 0.33 0.41 0.55 0.00 0:00 0.00 0.95 0.05 0.35 0.44 0.20 0.04 0.06 007 .74 0.92 A32 0.26 C 0.95 0.06 0.21 0.26 0.55 0.00 R00 0.00 0.95 0.03 0.11 0.14 0.20 0.17 0A3 0.17 0.45 0.56 A13 D.40 C 0.95 003 0.07 0.09 0.55 0.In III 0.00 0.95 0.23 O.Sfi 070 0.20 1.13 1.07 008 0.70 0.87 A14 0:09 B 0.95 0.00 0.00 BIC 0.55 0.00 0.00 0.00 0.95 0.02 0.21 0.26 0.15 0.07 0.12 0.15 0.32 0.41 AIS 0.49 B 0.95 O.Ofi 0.11 0.14 0.55 O.00 MID ODO 0.. I- 0.11 0.14 0.15 1.38 0.12 1,14 0.33 0.42 Alb 0.12 B 0.95 1 0.06 0.48 0.59 0.55 0.00 0.00 0.00 0.95 0.00 0.00 0.00 0.15 0.06 0.07 0.09 0.55 0.69 All 0.43 C 0.95 0.00 0.09 0.11 0.55 I.. OAO 1.. 0.95 0.09 -1 0.25 0.20 0.30 0.14 0.17 043 0.53 A18 0.72 B/C 0.95. 0.17 0.23 0.29 0.55 0.00 0.00 0.00 0.95 0,16 0.22 0.21 0.15 0.38 0.08 0.10 0.53 0.66 .S 0,35 C 0.95 0.13 0.37 0.4B 0.55 0.00 0.00 ODO 0.95 005 0.13 0.16 0.20 0.17 0-30 0.12 0.59 0.74 93 113 C 0.95 0.32 0.24 0.30 0.55 0.00 0.22 0.00 0.95 0.32 0.25 0.31 010 0.60 OAD 0.12 0.59 on B2 0.31 C 0.95 A. 0.55 0.69 0.55 0.In 000 0.00 0.95 0.07 0.20 0.25 0.20 006 0.04 OAS I.80 0.- CI 0.28 C 0.95 0.00 0.01 0.01 0.55 0.00 0.00 0.00 0.95 0.14 0.47 0.59 0.20 0.14 0.10 0.12 0,58 0.73 C2 0.32 C 0.95 0.02 0.06 0.07 0.55 I= 0.00 0.00 0.95 0.08 014 0.30 0:2U 0.22 0.14 0.17 0.4d 0.55 It 0.35 B 0.95 0.20 0.53 0.66 0.55 0.00 0.00 0.00 0.95 0.03 0.08 0.10 0.15 0.13 0.05 0.07 0.66 0.83 D2 0.22 C 0.95 1.11 0.48 0160 0.55 0.00 0.00 0.00 0.95 0.03 0.13 0.16 0.20 0.08 007 0.09 0.68 0.85 03 0.16 C 0.95 0.09 0.51 0.63 0.55 0.00 0.00 OAO 0.95 0.03 0.17 0.21 0.20 0.05 0.06 0.07 0.73 0.92 04 0.25 C 0.95 D14 1- 065 0.55 0.00 0.00 0.00 0.95 0.01 0.05 0.07 0.20 OSO 0.08 0.10 US 0.82 05 0.29 C OAS 0.15 0.49 0.61 0.55 0.00 0.00 0.00 0.95 0.05 0.16 0.20 0.20 0.09 0.06 0.08 0.71 0.89 06 0.29 C 0.95 0.16 0.54 0.sB D55 0.W III 0.W 0.95 0.01 0.03 003 0.20 1- 008. 0.10 0.65 0.81 07 0.11 C 0.95 0.07 0.63 0.78 0.55 0.00 0.00 0.00 0.95 0.02 0:20 0.25 0.20 0.01 0.03 0.03 0.86 1.00 09 0.19 C 0.95 0.15 0.75 0.94 0.55 0.00 0.00 0.00 0.95 OD2 0.12 0.15 0.20 0.02 0.02 0.02 1- 1.00 El 2.24 L 0.95 0.41 0.17 0.22 0.IS 1.10 0.27 0.34 0.95 0.00 000 0.00 1,20 2,73 0,M 0.08 0.51 0.64 E2 0.54 e/C 0.95 0.19 0.33 0.41 0.55 0- 0.23 0.29 0.95 0.00 0.00 0.00 0.15 0.12 0.03 004 0.60 0.75 E3 I! B/C 0.95 0.11 0.33 0.42 0.55 0.17 0.29 0.36 0.95 OM 0.00 OM 0.15 0.04 0.02 0.02 0.64 0.80 FS 3.92 C 0.95 0.04 0.01 0.01 0.55 053 0.07 0.09 0.95 1.00 0.24 0.. 0.20 2.36 0.12 1- 0.45 0.56 O51 0.61 C 0.95 0.00 1.00 O.W 0.55 0.00 0.00 O!W 0.95 0.09 0.14 0.18 010 0.52 0.17 0.21 0.31 0.39 052 0.09 C 0.95 0.03 0.34 0.43. 0.5 00.00 0.00 0.In I 0.95 I 0.01 0.15 0,18 010 0.04 0.30. 0.12 D.59 0.73 x.�191W».v11�34rv10I�axal0uiovye'av]9'!ot Orel CMc i®vYu_rin1.[Irm �e I af3 bIW3a2S Table 3.2-1.2 ft{laslliratian-R,n Co ld— landFlne Pugif Caeflltleal�{� PeddPRtlal urban Ertate 0.30 1pw oensiry Dss Medium Dens' a.. High Oerrsity o.gs cm a w Cemmertlal OBS Industrial 0.95 O nlands iransv00n 010 Greenbeky u110re 0.20 Table 1.2-2.S.H.—Type-RunaH Ca dens Surface Punofl co dmds Hartlsope or Hard Surface AspM1alt,concrete 0.95 Ruoftop 0.95 Rerynletl Az baR O.Bd Gravel 0.90 Pavers 0.50 tandsmpeorPervbussadace ns,San dy Soil,Fla[Slope<2% 0.10 Sandy Soil,Avg Slope 2- — wns,SandySoil,SteepSbpe>2% 0.20 ns,flayey Soil,flat 5lope<2% 0.20 ns,tla a SoiI,A Sio e2-2% 0.25 wns,Clayey Soil,Steep Sbpe>-!% 0.35 xvuroboovuarrvtol�eal�a.YryyavYszot n,ve�ce4.i®rYu_..zm.r.Ym yeezarz 2ng2n2s STANDARD FORM SF-2 TIME OF CONCENTRATION Subdivision:Polestar Project Name:Polestar Location:Fort Collins Project No.:39797.01 Calculated By:ARJ Checked By: Date:11/13/24 1 1 3 4 5 6 7 8 9 18 11 12 13 14 15 16 17 18 19 20 21 SUB-BASIN INITIAL/OVERLAND TRAVEL TIME Time of Concentration{heck DATA (TI) (T� (TO FINAL BASIN O.q. Nydwl481c ImpeNlous Cr4a L 5c tl-zvem tr-uIrt- Ie Sr K VEL to COMP.tea nor COMP.tczm,rn TOTAL Drbanhed 10 tesmr tuteova. ID (ac) SOIISGroup (%) (ft) (%) (min) (min) (R) (%) IBM (min) (min) (min) LENM(ft) (min) (Mn) (min). Al 1.02 C 16% 0.31 0.39 15 2.0% 20.7 1&7 104 8.8% 5.0 1.5 1.2 21.9 19.8 118.9 10.7 11.0 11.0 A2 0.58 C 52% 0.60 0.74 42.5 2.0% 22.4 15.8 105 2.1% 20.0 2.9 0.6 23.0 16.4 147.2 10.8 11.0 L1.0 A3 0.78 C 25% 0.39 0.49 50 4.0% 27.3 23.5 151 2.2% 15.0 2.2 1.1 28.4 24.6 200.7 11.1 11.0 11.0 A4 1.23 C 65% 0.70 0.87 12 3.0% 8.3 4.7 449 1.0% 20.0 2.0 3.8 12.1 8.5 461.1 12.6 12,0 90 A5 0.42 C 57% 0.65 0.92 5 2.0% 6.8 4.3 55 1.1% 15.0 1.5 0.6 7.4 4.9 60.0 10.3 7.0 5.0 A6 1.03 C 69% 0.72 0.90 13 2.0%. 9.4 5.0 643 0.9% 20.0 1.8 6.0 15A 11.0 655.5 13.6 14.0 11.0 A7 0.85 C 63% 0.67 0.84 13 2.0% 10.5 6.3 595 0.9% 20.0 1.9 5.2 15.7 11.5 607.8 n.4 13.0 12.0 AS 1 0.58 1 C "% I 0.84 S.W 1 12 3.0% 5.3 2.11 221 1.3%11 20.0 2.3 1.61 7.0 171 233.4 wl 7.0 5.0 A9.1 0.16 C 84% 0.87 1.00 51 2.0% 3.4 1.5 67 0.6% 20.0 1.6 0.7 4.1 2.2 72.0 10.4 5.0 5.0 A9.2 0.03 C 54% 0.80 1.00 5 2.0% 4.6 1.6 5 10.0% 20.0 6.3 0.0 4.6 1.6 10.0 10.1 5.0 S.D A10 0.09 C 85% 0.88 L.00 5 2.0% 3.3 1.5 30 3.4% 15.0 2.8 0.2 33 1.7 35.0 10.2 5.0 5.0 All 0,13 C 69% 0.74 0.92 5 2.0% 5.5 2.7 60 2.0% 15.0 2.1 0.5 5.9 3A 65.0 10.4 6.0 5.0 Al2 0.26 C 34% 0.45 0.56 5 2.0% 9.9 8.1 102 0.7% 15.0 1.3 1.3 11.2 9.5 107.3 10.6 11.0 9.0 A13 0,40 B 61% 0.70 0.87 5 2.0% 6.1 3.5 50 1.0% 15.0 1.5 0.6 6.7 4.0 55.0 10.3 TO 5.0 A14 0.09 B 21% 0.32 0.41 5 2.0% 11.8 10.6 20 2.4% 15.0 2.3 0.1 11.9 10.7 25.0 10.1 10.0 10.0 AIS 0.49 B 24% 0.33 0.42 5 2.0% 11.61 10.4 1191 1.4% 15.0 1.8 1.11 W 11.5 123.5 10.7 11.0 11.0 A16 1 0.12 1 51% 0.55 0.69 5 2.0% 8.4 6.3 54 0.7% 15.01 1.3 0.7 9.1 7.0 59.1 10.3 9.0 7.0 A17 0.43 B/C 30% 0.43 0.53 5 2.0% 10.2 8.6 113 1.8% 20.0 2.7 0.7 10.9 9.3 119.0 10.7 11.0 9.0 ASS 0.72 C 46% 0.53 0.66 30 14% 18.0 13.8 ISO 0.6% 15.0 1.1 2.2 20.2 16.0 180.0 11.0 11.0 11.0 A19 0.35 C 52% 0.59 0.74 5 3.4% 6.5 4.6 30 3.9% 15.0 3.0 0.2 6.7 4.8 35.0 10.2 7.0 5.0 81 1.23 C 50% 0.59 0.73 24 2.0% 17.1 12.2 175 0.5% 20.0 1A 2.1 19.2 14.3 199.0 11.1 11.0 11.0 B2 0.31 C 78% 0.80 0.99 24 2.0% 10.1 3.5 204 1.8% 20.0 2.7 1.3 11.4 4.8 228.0 113 11.0 5.0 C1 0,28 C 47% 0.58' 0.73 3 75.0% 2.8 L9 54 5.9% 20.0 4.9 01 2.8 2.1 57.0 10.3 5.0 5.0 C2 0.32 B 31% 0A4 0.55 5 2.0% 10.1 8.4 62 2.0% 15.0 2.1 0.5 10.6 8.9 67.0 10.4 10.0 9.0 Di 0,35 C 64% 0.66 1 0.83 1 24 2.0%1 14.51 9,0 54 0.8% 20.0 1.7 0.51 15.1 g.51 78.1 10.4 10.0 10.0 D2 0.22 C 63% 0.68 0.85 24 2.0% 14.1 8.5 871 0.8%1 20.0 1.7 0.8 15.0. 9.3 111.0 10.6 11.0 9.D D3 0.16 C 70% 0.73 0.92 24 2.0% 1212 6.1 60 0.8% 20.0 1.7 0.6 12.8 6.7 84.0 10.5 10.0 7.0 D4 0.25 C 61% 0.65 0.82 24 2.0% 14.8 9.4 65 0.8% 20.0 1.7 0.6 15.5 10.0 89.0 10.5 10.0 10.0 D5 0.29 C 67% 0.71 0.89 13 2.0% 9.5 5.1 231 2.0% 20.0 2.8 1.4 10.9 6.5 244.0 11.4 11.0 7.0 D6 0.28 C 60% 0.65 0.81 13 2.0% 11.0 7.1 2M 2.0% 20.0. 2.8 1.6 12.6 8.6 277.0 11.5 12.0 9.0 D7 011 C 85% 0.86 LOD 24 2.0% 8.2 3.3 60 0.8% 20.0 1.7 0.6 8.7 3.9 84.0 10.5 9.0 5.0 D8 R19 C 90%. 0.89 1.00 24 2.0% 7.1 3.3 83 0.8% 20.0 1.7 0.8 7.9 4.1 107.0 ME 9.0 5.0 El 2.24 C 41% 0.09 0.51 1 1301 4.0% 62.91 36.41 505 1.0% 20.0 2.0 4.11 67.0 40.5 635.3 US 14.0 14.0 E2 am B/C 54% 0.04 0.60 1 50 2.0% 50.9 24.2 270 20 1.0% .0 2.0 2.3 53.1 26.5 320.0 11.8 12.0 12.D E3 0.31 B/C 59% 0.02 O. 50 2.0% 51.8 22.1 143 1.1% 20.0 2.1 3.2 52.9 23.2 193.0 11.1 11.0 11.0 Fl 3.92 C 31% 0.15 0.45 1 50 1.0% 57.4 39.6 '475 0.5% 20.0 1A 5.6 63.0 451 525,0 12.9 13.0 13.0 051 0.61 C 15% 0.21 0.31 46 1.7% 43.4 M.6 66 1.4% 5.0 0.6 1.9 45.3 40.4 112.0 30:6 110 11.0 OS2 0.09 C 51% 0.12 0.59 50 1.0% 59.1 31.1 215 3.0% 20.0 3.5 1.0 60.2: 32.11 265.01 11.51 11.0 11.0 NOTES: T.=T+Tt Velocity V=MIM.S _ 7 eroes�mw Where�T,=Total Time of Concentration,minutes A xa�rr�a T,=Initial or Overland Flow Time of Concentration,minutes Tr=Channelized Flow In Swaale,Gutter or Plpe,minutes T=`-� ak.in.a�vwanoweaa•erw�. °war'n.na m,GmmuWess T`=+•^ ° sew•w..aas wMe4 rrepuemv 44hstnwm rector.elmenvonless lenpn olovemm rww,last Burro�e*. *.•r.w uee�o.•r� X:J91aMPxl11]9(9]OIIEacellOnmegV9l%01 nmim�Ceks T lou v3.Oti6m ge I o(I I I/25PA14 STANDARD FORM SF-3 STORM DRAINAGE SYSTEM DESIGN IRaTIONAL METHOD PROCEW Rfl Rmlea Name:v suhdh•Ision:Polertar Collins .1.1.1.dBy:ARJ Oeaign Sm'rm:2--year CReNed By: a 1]/13/20 IECTRUNOFF TOTAL RUNOFF STREETPIPE T VELTIME —EET - E = s 'e REMARKS - B.og 1a,R.B nw rromswMM IS, O.o9 0 Flow lnro Pen 0R4 OA4 12U.0.. 1. OA.9 grade Inlet-Drains m Pond 031 OA2 v.0 0.01 il3 O.pi AIR 039 0.11 7.1 0.20 2.52 Ob0 TW O.20 o ae y pasOcaw pp unoH Collseeh,d VI,Treneh orals and All pipe 0 oe ybpbstkantl PD3 pipe ll O,B3 0 0 0.1g 2 0.38 O.T6 O.e 0.3% ]e O.d0 0.)0. )A.0.2R 2 2 0.)i 0.3 0:2% ]:2 o Y PasOcaw PP unoRCollected Vl,Ryloplatkand_pipe B.g4 unoX caollne,hW vta Nylopbstkantl A0S pipe B.o9 B ae% B.)oaba�abAl3V uI una1 cdlecretl via Nybpbztk and All pipe Colleced tXa Nyloplaztk antl A0S pipe ., land All plpe ILO 0 13A 1,93 L4 1.4 O.i OS% L00 I, 91 91 0.9% trz igs 01- 11 1.. M% 0' 21 y p nd rypeclnlets 3:g All I unoX tlralnz to zumpinlet at Op Ta "I III 3:9 JR 1-3 R.nolm alley andremple homage anl.11—,Iby antltemple front,,, AgB 2 .el% 0.)easlns Aeantl Aa 1-1 From"" open span and remplelrontage 0 035 E 0.)0% oa tl rvnoAInto 1 Fpreha4-3azln A2-Ai9 LS, 129 5354-2 E41 sd Os% 30 STANDARD FORM SF-3 STORM DRAINAGE SYSTEM DESIGN (RATIONAL METHOD PROCEW RE) ___Name:v subdivision:Polertar Collins Calculated By:ARJ Oeaign Sm'rm:2--Year CbeNed By: a 1]/13/20 EE ECFRUM)FF TOTAL RUNOFF STREET PIPE —ELTIME —EET — E = s 'e REMARKS erfbw Into Ne Pokstar peten[IPn Pond S6T, 3A9 as 0.9% IRvertlowsantl aNm Npetl In Typepinl<t El"-oH Into ain gartlen ]10 0.9T i13 d} bl 6a% vertlow lnm pond Aa% 1p oHinm R� garden 9 M. _ 33 Lg% ertloiwtlnmlpnntl plp<d In Aps pipe Id 1 0.Y6 p.66 l 0 p.Y3 Ygl p.s In pl rurb<utm0.G 0. pig g den If,B 213 1} 18. 6p L vertloiwtlnmlpona � al Runoff Into 0.G iped runplf Into Noe[Inlet ssa aa� l:g .ka gasp aB 1am1'11.Pmenar p<tan on Pona 194 L LD A: Yg P�p<bPoainpspl 6rm<tan P A,ala<a aree<krmnea bvwl�amgd,e<ambn,<nr<Imepeq,awe. STANDARD FORM SF-3 STORM DRAINAGE SYSTEM DESIGN (RATIONAL METHOD PROCEDURE) Projed Name:Polestar Subdivision:Polestar Project No.:39797.01 Location:F-ClIlill Calculated By:AM Design Storm:lODYear Checked By: Date:11 13 24 UIRELTRUNOFF TOTALRUNOFF STREET PPE TRAVELTIME ti STREET '¢ REMARKS < It E E1 2.24 0.51 14.0 1.14 6.71 ].6 Flaw from SW MM 1]W 59.9 OSI 0.61 0.31 11.0 0.19 7.42 1.4 OS2 0.09 0.59 11.0 0.05 7.42 0.4 Flow into Pan le. 69.4 Flow Into Pan 2e E2 0.54 O.W 12.0 0.32 7.16 2.3 71.7 Flow Into pan and then swale Ong.de inlet-Mains W Pond 3e E3 0.31 0.64 I3.0 0,. 7A2 1.5 Runoff Collected Via NYloplastic and ADS pipe 19a A39 0.35 0.74 5.0 0.26 9.95 2:6 5.00 0.26 9;951 2.6 2:6 0.3. 0.5% 151 T941 IAJ 2.3 Drains-Basin A19 Runoff Collected Via Trench Drain and ADS pipe IRS A18 0.72 0.66 11.0 0.47 7.42 3.5 11.0 0,73 7.42 5.4 5.4 0.7 O.5% 18 139 1.4 1.6 Drains-Basin A19 and A18 Runoff Collected Via Nylopiastic and ADS pipe 17a All 0.43 0.53 9.a 0,23 8.03 1.8 12.. 0.96 7.02 6.7 6.7 Lo 0.3% 18 90 1.2 T.31 Drains-eosin A19,A18,and A17 Runoff Colleced Via NVlopiastic and ADS pipe 13a A39 0.40 0.81 5.0 0.35 9-.95 3.5 3.5 0.4 09% 12 50 1.4 04 Drains Basin Ala Runoff Collected Via NyloplastiC and ADS pipe - A15 0.49 0.42. 11.0 0.21 7A2 1.6 11.0 0.56 7.42 4.2 L2 0.2 0.8% 18 90 1.8 0.8 Drains Basin All,and AlS Runoff COIIe-d Via Nylopiastic and ADS pipe lea A. 0.09 TAI 10.0 ON7.72 0.3 ll.8 0.60 7.21 4.3 4.3 0.04 0.8% 18 ]D 1.8 0.7 Drains 9asln All,A15,A14 Runoff Collected Via NyloplastiC and ADS pipe i6a A16 0.12 0.69 7.0 0.08 8.80 0.7 12.5 0:68 7.M 4.8 4.8 0.1 0.8% 18 140 1.8 1.0 Drains easln All,A15,A14ard Alb 10. A10 0.09 1.00 5.0 0.09 9.95 0.9 0.9 0.1 4.8% 6 60 4.4 0.2 Runoff Collected Via Nyloplastip and A05pipe 1.1 13.5 0.77 6:12 5.2 5.2 0.8 0.5% 18 30 1.4 0.4 A33,AIS,A34,A16+A10 Runoff Collected Via Nyloplastic and ADS pipe 12. Al2 0.26 0.56 9.0 0.15 8.03 1.2 13.9 0.92 6,73 6.2 6.2 0.2 0.5% 18 15 1.4 0.2 A33,A15,A14,A16+Al0and Al2 Runoff Collectetl Vla Nylopiastic and AD5 pipe Ila All 0.13 0.92 5.0 0.12 9.95 1.2 1.2 0.1 5.0% 6 9 4.5 0.0 A33,A35,A14,A16+A10and Al2,All 1.2 1 14-11 2.00 US 114 13.4 2.0 0.5% 24 90 1.4 1.1 Collected Runoff Basins All-A19 9.1A A9.1 0.161 1.001 5.0 0.16 9.93 1.6 1.6 0.2 2.5% 8 20 3.2 0.1 9.2. A9.2 0.03 1.00 I.0 I. 9.95 0.3 11.1 2.11 6.48 14.2 14.2 2.2 0.5% 24 230 1.4 2.7 Total Runoff Basins 9.1.-19a Court-yard Sa AS 0.42 0.82 5.0 0.34 9.95 3.4 Drainsto nyloplaticandtypeCinlets 1.3 17.9 2.53 5.- 35:o 15,0 2.5 0.5% 24 400 1.4 4.7 %.unmm.aWSlYmncwen0,emaaevVzafii u,awy�cola rzmphR vloiabm vaeei orz iii35�Zn'z� STANDARD FORM SF-3 STORM DRAINAGE SYSTEM DESIGN (RATIONAL METHOD PROCEDURE) ProJed Name:Polestar Subdivision:Polestar Project No.:39797.01 Location:Fort Co ins Calculated By:AM Design Storm:10G-Year Checked By: Date:11 13 24 DIRECTRUNOFF TOTALRUNOFF STREET PPE TRAVELTIME ti _ STREET - _ - _ "¢' REMARKS It Runoff drains tosump11111 t0p7a 7. p7 0.85 0.84 12.0 0.73 7.16 5.1 1.4 116 3.24 5.25 17.0 1 170 32 05% 30 22 1.4 0. RunoffFrom alley and temple frontage 8a AS 0.58 LW 5.0 0.58 9.95 5.8 5.8 0.58 0.81%. 217 1.9 1.9.rains to Plum Street Basin A8 Runoff From alleys and temple frontage qa A4 1.23 0.87 9.0 1.07 8.03 8.6 9.. 1.65 8.03 13,2 13.2 1.07 0.87% 83 1.9 0.7 Basins AB and A4 Runoff From alleys,open space and temple frontage 38 A3 WE 0.49 11.0 0.38 7.42 2.9 11.0 2.03 7.42 15.1 15.1 0.38 0..7% 74 1.9 0.7 Basins A8,A4,and A3 Runoff From alleys,open space and temple frontage 2. A2 0.58 0.14 11.0 0.43 7.42 3.2 11.7 2.46 7.24 17.8 17.8 0.43 0.70% US 1.7 1.2 Resins M,A4,and A3,A2 To If-to sump Inlet at DP 6a Ba A6 1.03 0.90 11.0 0.92 7.42 6.8 12.9 3.38 6,94 23.5 Basins An,AS,As,and A3,A2 Toatl rvnoff Into RG Forebi y-Basin A2-A19 1.5 22.9 6.62 5.21 34.5 34.5 6;6 0.5% 30 Al 1.02 0.39 11.0 0.40 7.42 3.0 Overflow inn.the P.1-1,.etenti-Pond 16 7AI 22.9 702 5,21 36A 36.6 OS% 30 Overflows andis then Pped in Type D Inlet To Bl 1.23 0.73 11.0 0.90 7A2 6.7 2b B2 0.31 0A9 5.0 0.31 9.95 3.1 Runoff Into in garden 11 11.0 1.21 7.42 9.0 9,0 64% S Overflow into pond Runoff Imo RG lc Cl 0.28 M73 5.0 0:21 9.9S 2.1 Runoff ido RG 20: C2 0L32 0.55 9.0 0.18 8.03 IA 1.4 (L 10 7d D7 0.11 100 5.0 0.11 9.95 1A 8d 08. 0.19 1.00 5.0 0.19 9.95 1.9 5.0 0.30 9.95 3.0 Runciff Into rain garden 31 9.0 069 8.03 5.5 5.5 1;8% 12 Overflow into pond piped In ADS pipe Basin Dl Sd D1 035 0.83 10.0 0.29 7,72 23 Dram:via curb in to RG 2d D2 0.22 0.85 9.0 0.18 8.03 1.4 10:0 0.47 7.72 3.6 Basins Dl and D2 Grains via curb Cut to RG 3d D3 0.16 0.92 7.0 0.15 9.80 1.3 UTu 0.E2 7.72 4.8 1 1 1 Bain ss D1,02 and D3 R H nto.raingarden 4.1 10.0 0.62 7.72 4.8 48. 0% 10 60 1.4 0.7 OverRow Into:pond Runoff Into RG 5d DS 0.29 0.89 7-0 0.2621.61- Total RUnoff into RG 4d OQ 0.25 0.82 10.0 0.21 7.]2 3.6Pipedrunaff into type C inlet4.2 7.51 8.2 9.2 05% 2 173 1.4 2A Runoff Drains into RG Drains via Curb Cut 6d .6 0.28 0.81 9.0 0.23Runoff..i'sintoPolesaroerentionpon 4.3 6.99 9.2 9:2 0:R% 24 Plead Basin DT+Ol Note,: Street and Pipe C-A values are determined by 0/1 usingthe catchment-,intensity value. %.VvnmoaW sielc l000eae1-1 rnameb�caiu z[mphR vlprabm analxorz DR3.xr OVERFLOW CHANNEL CC - RIPRAP CALCULATIONS Subdivision: Polestar Village Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Calculated By: ARJ Checked By: Overflow at DP 5.1 Date: 8/21/24 RIP-RAP METHOD-ISBASH Method D50=stone size(ft) — a" V a=average channel velocity(ft/s) G s=specific gravity of stone G " — 1 G=gravitational constant(ft/s A2) �j J C=0.86 for high turbulence zones 1.20 for low turbulence b zones Pay Item Percent of Material Typical Typical Stone Stone Stone Size Smaller Than rLSU� Dimensions' 3V'0gheiRhl'' Value UnitsnitS Typical(Tnehes) Slone (Inches} (1'omtds) Va 8.5 ft/s 70-100 12 95 Gs 2.5 50-�o U 35 �PTa1' 35-50 6 10 Gs 32.2 (ft/s A2) 2-10 2 a.a C 1 70-100 15 160 Rtprip g 50-70 l2 85 35-50 9 35 2-10 3 1.3 70-100 21 440 D(50) 0.75 feet aturap 12 50-70 is 275 35-50 12 85 D(50) 1 91 inches 1 2-10 4 3 100 30 0280 lvpnp 1a 50-70 24 650 35-50 LS 275 *using typem riprap-12" 2-10 6 10 100 42 3500 Riluap 24 50-70 33 1700 35-50 24 fi50 2-10 9 3S 'd-50=nominal stnne size based©n typical rack mass 'e<ryivalent7 eaical diameter •bated t l 111eific g—i,ty-2 5 PIPE OUTFALL RIPRAP SIZING CALCULATIONS subdivision:Polestar Project Name:Polestar laatlon:Fort Collinsrt CD PmI-No.:39797.01 Ulculated By:AFU Checked By: Date:2 10 24 STORM DRAIN SYSTEM DESIGN POINT-2.1 DESIGN POINT-3.1 DESIGN POINT-4.3 Design Point Be DESIGN POINT-1.6 Notes Qta�(cfs): 9.0 5.5 9.2 1.5 36.6 Conduit Pipe Pipe Pipe Pipe Pipe D„pipe Diameter(in): 12 12 18 15 30 W,Box Width(ft): N/A N/A N/A N/A N/A H,Box Height(ft): N/A N/A N/A N/A N/A YI,Tailwater Depth(ft): 0.40 0.40 0.40 OAO 1.88 If unknown,use Y,/D,(or H)=0.4 Y,JOc or Y,/H 0.40 0.40 0.27 0.31 0.75 Pond Tw assumed to be a1.75 Yt/H for DP 1.1 0/D"or O/(WHai') 8.98 5.54 3,35 O.RS 3.70 Supercritical? Yes Yes Yes Yes Yes Y_Normal Depth(ft)[Supsrcritidall: 0.72 0.58 :0.63 0.53 2.50 Do,H,(in)[Supercritical]: 0.86 0.79 1.07 0.89 2.50 Riprap dsp(in)[Supercritical]: 7.79 4.93 7.51 1.27 3.61 Riprap ds (in)[Subcrlticall: N/A N/A N/A N/A N/A Required Riprap Size: L L L L L Fie•9-38 or Fig.9.36 dw(in): 9 9 9 9 9 Using type M Riprap Expansion Factor,1/(2 tanO). 3.00 3.00 3.00 3.00 3,00 Read from Fig.9-35 or 9-36 @: 0.17 0.17 0.17 0.17 0.17 Erosive Soils? No No No Yes No Area of Flow,A,(ft'): 1.28 0.79 1.32 0.30 5.23 A,=O/V Length of Protection,L,(ft). 6.6 2.9 5.4 -1.5 0.9 L=(1/(2 tan 0))IAt/Yt-D) Min Length(ft) 3.0 3.0 4.5 3.8 7.5 Min L=3D or 3H Max Length(ft) 10.0 10.0 15.0 12.5 25.0 Max L=10D or JOH Min Bottom Width,T(ft): 3.2 2.0 3.3 0.7 2.8 T=2'(Lp'tar9)+W Design Length(ft) 7.0 3.0 6.0 3.8 7.5 Design Width(ft) 3.2 2.0 3.3 0.7 2.8 Riprap Depth(in) 18 18 18 16 18 Depth=2(dso) Type 11 Bedding Depth(in)- 6 6 6 6 6 -Not used if Soil Riprap Cutoff Wall No No No No Yes Cutoff Wall Depth(ft) 2.0 Depth of Riprap and Base Cutoff wall Width(k) 8.3 Note:No Type ll Base to oe used if Soil Riprap is specified within the plans 'Far use when the RoVd in the culvertis supercritical(and lessthan full). USE TYPE M RIPRAP-TYPE L USE IS NOT ALLOWED PER CITY OF FORT COLLINS-2018 FCSCM X-a11-]97anFsrehD ge-7n1 IDslnege Cilev Templme v2.a7.xkm Page lof]JIM2n25. 6+Eap.mla ANIM a r - fIH 5 B ga o a o b 6 / I- TAILWATER DEPTH/CONDUIT HEIGHT•Yr/D f liu'n v-}<,ripx.•In.lunar l.r rllrulxr rns•tu P• 9•E.Pa.lw Ami. 7 6 a 3 I/e b' z 0 0 .1 2 .S • 3 .6 .r e 9 10 TAILWATER DEPTH/CONDUIT HEIGHT-YI/H Tits.9-36.E.P..W./.nor 1'.r feclnd.l.r—d.11. X:--919'Im—orem W-701—W Cilev Templ.—T.km ftg 2—ZIW025. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Calculated By: ARJ Checked By: Date: 11/13/24 Private Drains v t v CL G1 v H *' O N Q o a ° c '^ 00 - a a a° 0 v c o C a` 19a 2.6 0.50% 1.01 15 18a 5.4 0.50% 1.33 18 17a 6.7 0.34% 1.51 18 13a 3.5 0.90% 0.98 12 15a 4.2 0.78% 1.11 18 14a 4.3 0.78% 1.13 18 16a 4.8 0.78% 1.17 18 10a 0.9 4.75% 0.44 6 1.1 5.2 0.50% 1.32 18 12a 6.2 0.50% 1.40 18 11a 1.2 5.00% 0.49 6 1.2 13.4 0.50% 1.87 24 9.1A 1.6 2.50% 0.62 8 9.2a 14.2 0.50% 1.91 24 4.1 4.8 0.47% 1.29 18 4.2 8.2 0.50% 1.56 24 3.1 1 5.5 1 1.80% 0.99 12 2.1 1 9.0 1 6.54% 0.991 12 2c 1 1.4 1 0.44% 0.831 10 n=0.013 typ. n=0.012 for DPI 7a,13a and 3.1 See Equation Below: Minimum Diameter Gf Circular Pipe Under Fall Flow Conditions Coo' 5 a WheTe Depth y is constant. D =diameter of pipe(ft) CO =2.16 fvr USCS units 0 =Ilo w(ft i sec) n =Marmirug's roughness coefficient S =slope(fun) X:\3970000.all\3979701\Excel\Drainage\3979701 Drainage_Calcs_Template_v2.07.xlsm Page I of 1 11/25/2024 20 APPENDIX C - HYDRAULIC CALCULATIONS Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input Type of Grate 12"Pedestrian Nyloplast Head(ft) 0.2 Properties Orifice Flow Area(in) 50.6 Orifice Flow Area(ft) 0.35 Weir Flow Perimeter(in) 43.25 Weir Flow Perimeter(ft) 3.60 Solution Capacity(cfs) 0.75 Capacity(gpm) 337.28 Design Point 100 YR(cfs) 9.1a 1.6 No of inlets 3 Total Cap.(cfs) 2.25 FS 1.42 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient L=Perimeter of Grate Opening(ft) H=Flow Height of Water SurfaceAbove Weir(ft) Q,rtfic.=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 g=Gravitational Constant(32.2sf2� `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input Type of Grate IType C Head(ft) 0.1 Properties Orifice Flow Area(in) 907.2 Orifice Flow Area(ft) 6.30 Weir Flow Perimeter(in) 144.00 Weir Flow Perimeter(ft) 12.00 Solution Capacity(cfs) 1.26 Capacity(gpm) 567.12 Design Point 100 YR(cfs) 9.2a 14.2 No of inlets 1 Total Cap.(cfs) 1.26 FS 0.09 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient Note:using CDOT Type C Inlet L=Perimeter of Grate Opening(ft) H=Flow Height of Water SurfaceAbove Weir(ft) Q,rtfic.=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 t ns \f g=Gravitational Cotant(32.252 `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input //AM Type of Grate 15"Pedestrian Nyloplast Head(ft) 0.18 Properties Orifice Flow Area(in) 81.25 Orifice Flow Area(ft) 0.56 Weir Flow Perimeter(in) 54.25 Weir Flow Perimeter(ft) 4.52 Solution Capacity(cfs) 1.14 Capacity(gpm) 513.78 Design Point 100 YR(cfs) 10a 0.9 No of inlets 1 Total Cap.(cfs) 1.14 FS 1.28 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient L=Perimeter of Grate Opening(ft) H=Flow Height of Water SurfaceAbove Weir(ft) Q,rtfic.=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 g=Gravitational Constant(32.2sf2� `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input Type of Grate 18"Drop In Nyloplast Head(ft) 0.6 Properties Orifice Flow Area(in) 84.61 Orifice Flow Area(ft) 0.58 Weir Flow Perimeter(in) 48.00 Weir Flow Perimeter(ft) 4.00 Solution Capacity(cfs) 2.18 Capacity(gpm) 976.83 Design Point 100 YR(cfs) 11a 1.2 No of inlets 1 Total Cap.(cfs) 2.18 FS 1.82 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient L=Perimeter of Grate Opening(ft) H=Flow Height of Water SurfaceAbove Weir(ft) Q,rtfic.=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 g=Gravitational Constant(32.2sf2� `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input Type of Grate 24"Drop In Nyloplast Head(ft) 0.4 Properties Orifice Flow Area(in) 164.94 Orifice Flow Area(ft) 1.14 Weir Flow Perimeter(in) 66.28 Weir Flow Perimeter(ft) 5.52 Solution Capacity(cfs) 3.46 Capacity(gpm) 1554.81 Design Point 100 YR(cfs) 12a 6.2 No of inlets 1 Total Cap.(cfs) 3.46 FS 0.56 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient Note:Additional inlets one 12" -Drop in inlet and one 18"drop in inlet L=Perimeter of Grate Opening(ft)H=Flow Height of Water SurfaceAbove Weir(ft) have been added to capture flow along this run associated with DP 12a along the swale and at Tee's CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 t ns \f g=Gravitational Cotant(32.252 `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input Type of Grate 18"Drop In Nyloplast Head(ft) 0.55 Properties Orifice Flow Area(in) 84.61 Orifice Flow Area(ft) 0.58 Weir Flow Perimeter(in) 48.00 Weir Flow Perimeter(ft) 4.00 Solution Capacity(cfs) 2.08 Capacity(gpm) 935.24 Design Point 100 YR(cfs) 13a 3.5 No of inlets 3 Total Cap.(cfs) 6.25 FS 1.80 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient L=Perimeter of Grate Opening(ft) H=Flow Height of Water SurfaceAbove Weir(ft) Q,rtfic.=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 t ns \f g=Gravitational Cotant(32.252 `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input //RYA Type of Grate 12"Drop In Nyloplast Head(ft) 0.3 Properties Orifice Flow Area(in) 39.75 Orifice Flow Area(ft) 0.27 Weir Flow Perimeter(in) 33.31 Weir Flow Perimeter(ft) 2.78 Solution Capacity(cfs) 0.72 Capacity(gpm) 324.50 Design Point 100 YR(cfs) 14a 4.3 No of inlets 1 Total Cap.(cfs) 0.72 FS 0.17 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient L=Perimeter of Grate Opening(ft) H=Flow Height of Water SurfaceAbove Weir(ft) Q,rtfic.=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 g=Gravitational Constant(32.2sf2� `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input //t= Type of Grate 18"Drop In Nyloplast Head(ft) 0.2 Properties Orifice Flow Area(in) 84.61 Orifice Flow Area(ft) 0.58 Weir Flow Perimeter(in) 48.00 Weir Flow Perimeter(ft) 4.00 Solution Capacity(cfs) 1.19 Capacity(gpm) 534.73 Design Point 100 YR(cfs) 15a 4.2 No of inlets 2 Total Cap.(cfs) 2.38 FS 0.57 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient L=Perimeter of Grate Opening(ft) H=Flow Height of Water SurfaceAbove Weir(ft) Q,rtfic.=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 g=Gravitational Constant(32.2sf2� `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input Type of Grate 12"Drop In Nyloplast Head(ft) 0.2 Properties Orifice Flow Area(in) 39.75 Orifice Flow Area(ft) 0.27 Weir Flow Perimeter(in) 33.31 Weir Flow Perimeter(ft) 2.78 Solution Capacity(cfs) 0.59 Capacity(gpm) 264.96 Design Point 100 YR(cfs) 16a 4.8 No of inlets 2 Total Cap.(cfs) 1.18 FS 0.25 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient L=Perimeter of Grate Opening(ft) H=Flow Height of Water SurfaceAbove Weir(ft) Q,rtfic.=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 t ns \f g=Gravitational Cotant(32.252 `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input Type of Grate 18"Drop In Nyloplast Head(ft) 0.1 Properties Orifice Flow Area(in) 84.61 Orifice Flow Area(ft) 0.58 Weir Flow Perimeter(in) 48.00 Weir Flow Perimeter(ft) 4.00 Solution Capacity(cfs) 0.42 Capacity(gpm) 189.06 Design Point 100 YR(cfs) 17a 6.7 No of inlets 6 Total Cap.(cfs) 2.53 FS 0.38 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient Note:6 inlets along shallow swale designed to capture flow L=Perimeter of Grate Opening(ft) H=Flow Height of Water SurfaceAbove Weir(ft) Q,rtfic.=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 t ns \f g=Gravitational Cotant(32.252 `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input AAAType of Grate 18"Drop In and Trench drain Nyloplast Head(ft) 0.1 Trench Drain Properties Inlet Length (ft) 133 Orifice Flow Area(in) 84.61 Opening(in) 5 Orifice Flow Area(ft) 0.58 Area-(ft) 55.42 Weir Flow Perimeter(in) 48.00 Perimeter(ft) 266.83 Weir Flow Perimeter(ft) 4.00 Capacity 28.10 Solution Capacity(cfs) 0.42 Capacity(gpm) 189.06 Design Point 100 YR(cfs) 18a 5.4 No of inlets+Trench Drain 2 Inlets and 1 Trench drain Total Cap.(cfs) 28.94 FS 5.34 Qweir=CLH3/2 C=3.33 Weir Discharge Coefficient Note:Trench drain along shallow swale designed to capture flow t=Perimeterof Grate opening(ft)H=Flow Height o f Water Surface Above Weir(ft) Swale is at 0.5%One Small 8"inlet to capture nuisance flows in this basin Ql.fKa=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice Utz g=Gravitation¢!Constant�32.2fftt///I s� H=Depth a f Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input Type of Grate 12"Pedestrian Nyloplast Head(ft) 0.17 Properties Orifice Flow Area(in) 50.6 Orifice Flow Area(ft) 0.35 Weir Flow Perimeter(in) 43.25 Weir Flow Perimeter(ft) 3.60 Solution Capacity(cfs) 0.69 Capacity(gpm) 310.95 Design Point 100 YR(cfs) 19a 2.6 No of inlets 4 Total Cap.(cfs) 2.77 FS 1.07 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient L=Perimeter of Grate Opening(ft) H=Flow Height of Water SurfaceAbove Weir(ft) Q,rtfic.=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 g=Gravitational Constant(32.2sf2� `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input Type of Grate 24"Dome Nyloplast Head(ft) 0.375 Properties Orifice Flow Area(in) 265.19 Orifice Flow Area(ft) 1.83 Weir Flow Perimeter(in) 71.47 Weir Flow Perimeter(ft) 5.96 Solution Capacity(cfs) 4.55 Capacity(gpm) 2044.06 Design Point 100 YR(cfs) 2.1 9.0 No of inlets 2 Total Cap.(cfs) 9.11 FS 1.01 Qweir=CLHa!'- C=3.33 Weir Discharge Coefficient Note:overflow path directley into pond L=Perimeter of Grate Opening(ft) H=Flow Height of Water Surface Above Weir(ft) Qo,j,=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(ftz g=Gravitational Constant l(32.2 f) H=Depth of WaterA bone Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input Type of Grate 18"Dome Nyloplast Head(ft) 0.43 Properties Orifice Flow Area(in) 170.74 Orifice Flow Area(ft) 1.18 Weir Flow Perimeter(in) 53.85 Weir Flow Perimeter(ft) 4.49 Solution Capacity(cfs) 3.72 Capacity(gpm) 1668.75 Design Point 100 YR(cfs) 3.1 5.5 No of inlets 2 Total Cap.(cfs) 7.44 FS 1.34 Qweir=CLHa!'- C=3.33 Weir Discharge Coefficient Note:overflow path directly into pond L=Perimeter of Grate Opening(ft) H=Flow Height of Water Surface Above Weir(ft) Qo,j,=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(ftz g=Gravitational Constant l(32.2 f) H=Depth of WaterA bone Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input Type of Grate IType C Head(ft) 0.20 Properties Orifice Flow Area(in) 907.2 Orifice Flow Area(ft) 6.30 Weir Flow Perimeter(in) 144.00 Weir Flow Perimeter(ft) 12.00 Solution Capacity(cfs) 3.57 Capacity(gpm) 1604.07 Design Point 100 YR(cfs) 6d 1.8 No of inlets 1 Total Cap.(cfs) 3.57 FS 1.94 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient Note:using CDOT Type C Inlet L=Perimeter of Grate Opening(ft) H=Flow Height of Water SurfaceAbove Weir(ft) Q,rtfic.=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 t ns \f g=Gravitational Cotant(32.252 `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input //AM Type of Grate 18"Dome Nyloplast Head(ft) 0.25 Properties Orifice Flow Area(in) 170.74 Orifice Flow Area(ft) 1.18 Weir Flow Perimeter(in) 53.85 Weir Flow Perimeter(ft) 4.49 Solution Capacity(cfs) 1.87 Capacity(gpm) 838.32 Design Point 100 YR(cfs) 4.1 4.8 No of inlets 4 Total Cap.(cfs) 7.47 FS 1.56 Qwnr=CLHa!'- C=3.33 Weir Discharge Coefficient L=Perimeter of Grate Opening(ft) H=Flow Height of Water Surface Above Weir(ft) Qo,j,=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(ftz g=Gravitational Constant l(32.2 f) H=Depth of WaterA bone Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. Subdivision: Polestar Project Name: Polestar Location: Fort Collins Project No.: 39797.01 Design Storm: 100-Year Calculated By: ARJ Checked By: Date: May-24 Input Type of Grate IType C Head(ft) 0.6 Properties Orifice Flow Area(in) 907.2 Orifice Flow Area(ft) 6.30 Weir Flow Perimeter(in) 144.00 Weir Flow Perimeter(ft) 12.00 Solution Capacity(cfs) 14.13 Capacity(gpm) 6340.64 Design Point 100 YR(cfs) 4d 3.6 No of inlets 1 Total Cap.(cfs) 14.13 FS 3.89 Q,,.,;r=CLH31= C=3.33 Weir Discharge Coefficient Note:using CDOT Type C Inlet L=Perimeter of Grate Opening(ft) H=Flow Height of Water SurfaceAbove Weir(ft) Q,rtfic.=CA 2gh C=0.60 Orifice Discharge Coefficient A=Area of the Orifice(,ft2 t ns \f g=Gravitational Cotant(32.252 `` H=Depth of Water Above Center of Orifice(ft) uses the lesser of these two equations DISCLAIMER:SAFETY FACTORS ARE NOT INCLUDED IN THESE CALCULATIONS.ACTUAL CALCULATIONS SHOULD BE CARRIED OUT AND VERIFIED BY THE DESIGN ENGINEER TAKING INTO ACCOUNT ALL LOCAL CONDITIONS.NYLOPLAST RECOMMENDS USING A REV 2.1.21 MINIMUM SAFETY FACTOR OF 1.25 FOR PAVED AREAS AND 2.0 FOR TURF AREAS.ADS/NYLOPLAST IS NOT RESPONSIBLE FOR MISUSE OF THIS TOOL. MHFD-Inlet Version 5.03(August 2023 e - • (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Project:Polestar Inlet ID:Inlet DP 6a T T,TY,,. sack w T. STREET cRowN Gutter Geometry: Maximum Allowable Width for Spread Behind Curb TBACK= 13.0 ft Side Slope Behind Curb(leave blank for no conveyance credit behind curb) SBACK= 0.020 ft/ft Manning's Roughness Behind Curb(typically between 0.012 and 0.020) nMCK= 0.016 Height of Curb at Gutter Flow Line HCURB= 6.00 inches Distance from Curb Face to Street Crown TCROWN= 16.0 ft Gutter Width W= 2.00 ft Street Transverse Slope SX= 0.020 ft/ft Gutter Cross Slope(typically 2 inches over 24 inches or 0.083 ft/ft) SW= 0.083 ft/ft Street Longitudinal Slope-Enter 0 for sump condition So= 0.000 ft/ft Manning's Roughness for Street Section(typically between 0.012 and 0.020) nsrRBFr= 0.016 Minor Storm Major Storm Max.Allowable Spread for Minor&Major Storm TAX=1 5.0 16.0 Ift Max.Allowable Depth at Gutter Flowline for Minor&Major Storm dM K= 6.0 12.0 linches Check boxes are not applicable in SUMP conditions F- F- MINOR STORM Allowable Capacity is not applicable to Sump Condition Minor Storm Major Storm MAJOR STORM Allowable Capacity is not applicable to Sump Condition Q,i„„= SUMP SUMP cfs MHFD-Inlet v5.03.xlsm,Inlet DP 6a 11/25/2024,11:02 AM MHFD-Inlet, Version 5.03(August 2023) Lo(C) H-Curb H-Vert W WP\ = `Lo(G) Design Information(Input) MINOR MAJOR FC unit length 3 Type of Inlet User-Defined Combination Type= User-Defined Combination Local Depression(additional to continuous gutter depression'a'from above) aio.i= 2.00 inches Number of Unit Inlets(Grate or Curb Opening) No= 6 Water Depth at Flowline(outside of local depression) Pending Depth= 5.0 7.3 inches Grate Information MINOR MAJOR i✓override Depths Length of a Unit Grate L.(G)= 3.00 3.00 feet Width of a Unit Grate W,= 2.00 00 feet Open Area Ratio for a Grate(typical values 0.15-0.90) Amto= 0.60 Clogging Factor for a Single Grate(typical value 0.50-0.70) Ct(G)= 0.50 0.50 Grate Weir Coefficient(typical value 2.15-3.60) Cw (G)= 3.00 -00 Grate Orifice Coefficient(typical value 0.60-0.80) C,(G)= 0.67 0.67 Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening L.(C)= 3.00 00 feet Height of Vertical Curb Opening in Inches Hen= 6.00 00 inches Height of Curb Orifice Throat in Inches Hthm t= 6.00 00 inches Angle of Throat Theta= 0.00 0.00 degrees Side Width for Depression Pan(typically the gutter width of 2 feet) WP= 2.00 2.00 feet Clogging Factor for a Single Curb Opening(typical value 0.10) Q(C)= 0.10 0.10 Curb Opening Weir Coefficient(typical value 2.3-3.7) C (C)= 3.00 Curb Opening Orifice Coefficient(typical value 0.60-0.70) Co(C)= 0.67 Low Head Performance Reduction(Calculated) MINOR MAJOR Depth for Grate Midwidth dG�to= 0.42 0.61 ft Depth for Curb Opening Weir Equation do,,,b= 0.25 0.44 ft Grated Inlet Performance Reduction Factor for Long Inlets RFG to= 0.47 0.69 Curb Opening Performance Reduction Factor for Long Inlets RFon,b= N/A N/A Combination Inlet Performance Reduction Factor for Long Inlets RFoombination= 0.47 0.69 MINOR MAJOR Total Inlet Interception Capacity(assumes clogged condition) Q,= 8.8 25.8 In Iniet Capacity IS GOOD for Minor and Major Storms > Peak Q PFAK REQUIRED= S.2 23.5 cfs City of Fort Collins Criteria Cw=3.0 Co=0.67 MHFD-Inlet v5.03.xlsm,Inlet DP 6a 11/25/2024,11:02 AM MHFD-Inlet Version 5.03(August XZ MIN (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Project: Polestar Inlet ID: Inlet DP 7a T T,T Se"u` W T. OWN R C CROWN e / Gutter Geometry: Maximum Allowable Width for Spread Behind Curb T-CK= 13.0 ft Side Slope Behind Curb(leave blank for no conveyance credit behind curb) SMCK= 0.020 ft/ft Manning's Roughness Behind Curb(typically between 0.012 and 0.020) nmcK Height of Curb at Gutter Flow Line HcuR = 6.00 inches Distance from Curb Face to Street Crown TCRCWN= 18.0 ft Gutter Width W= 2.00 ft Street Transverse Slope Sx= 0.020 ft/ft Gutter Cross Slope(typically 2 inches over 24 inches or 0.083 ft/ft) SW= 0.083 ft/ft Street Longitudinal Slope-Enter 0 for sump condition So= 0.000 ft/ft Manning's Roughness for Street Section(typically between 0.012 and 0.020) nMEET= 0.016 Minor Storm Major Storm Max.Allowable Spread for Minor&Major Storm TIM = 16.0 16.0 ft Max.Allowable Depth at Gutter Flowline for Minor&Major Storm d,4m=1 6.0 12.0 inches Check boxes are not applicable in SUMP conditions r MINOR STORM Allowable Capacity is not applicable to Sump Condition Minor Storm Major Storm MAJOR STORM Allowable Capacity is not applicable to Sump Condition Q,iio„= SUMP SUMP cfs MHFD-Inlet_v5.03.xism,Inlet DP 7a 11/13/2024,1:17 PM OR SAG LOCATION MHM-Inlet, Version 5.03(August 2023) Lo(C) H-Curb H-Vert Wo _ WF, W �-Lo(G) Design Information(Input) MINOR MAJOR User-Defined Combination Type of Inlet Type= User-Defined Combination Local Depression(additional to continuous gutter depression'a'from above) am,i= 2.00 inches Number of Unit Inlets(Grate or Curb Opening) No= 2 Water Depth at Flowline(outside of local depression) Ponding Depth= 5.4 5.5 inches Grate Information MINOR MAIOR r Override Depths Length of a Unit Grate Lo(G)= 3.00 'nn feet Width of a Unit Grate W.= 2.00 feet Open Area Ratio for a Grate(typical values 0.15-0.90) A. = 0.31 Clogging Factor for a Single Grate(typical value 0.50-0.70) Q(G)= 0.50 0.50 Grate Weir Coefficient(typical value 2.15-3.60) C (G)= 3.00 Grate Orifice Coefficient(typical value 0.60-0.80) Co(G)= 0.67 Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo(C)= 3.00 a feet Height of Vertical Curb Opening in Inches H_rt= 6.00 inches Height of Curb Orifice Throat in Inches Hthmat= 6.00 inches Angle of Throat Theta= 0.00 degrees Side Width for Depression Pan(typically the gutter width of 2 feet) WP= 2.00 feet Clogging Factor for a Single Curb Opening(typical value 0.10) Ct(C)= 0.10 0.10 Curb Opening Weir Coefficient(typical value 2.3-3.7) C (C)= 3.00 u Curb Opening Orifice Coefficient(typical value 0.60-0.70) C.(C)= 0.67 Low Head Performance Reduction(Calculated) MINOR MAJOR Depth for Grate Midwidth dGr�= 0.45 0.46 ft Depth for Curb Opening Weir Equation dory= 0.28 0.29 ft Grated Inlet Performance Reduction Factor for Long Inlets RFGra�= 0.63 0.65 Curb Opening Performance Reduction Factor for Long Inlets RFo,r = N/A N/A Combination Inlet Performance Reduction Factor for Long Inlets RI`Umwnmon= 0.63 0.65 MINOR MAIOR Total Inlet Interception Capacity(assumes clogged condition) Qacfs Inlet Capacity IS GOOD for Minor and Major Storms > Peak Q PEAK REQUIRE"= 1.1 5.1 cfs City of Fort Collins Criteria Cw=3.0 Co=0.67 MHFD-Inlet_v5.03.xism,Inlet DP 7a 11113/2024,1:17 PM MHFD-Inlet Version 5.03(August XZ MIN (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Project: Polestar Inlet ID: Inlet DP 3e T,. se u_ w T. STREET GROWN e / Gutter Geometry: Maximum Allowable Width for Spread Behind Curb T-CK= 13.5 ft Side Slope Behind Curb(leave blank for no conveyance credit behind curb) SMCK= 0.02I ft/ft Manning's Roughness Behind Curb(typically between 0.012 and 0.020) nmcK Height of Curb at Gutter Flow Line HcuR = 6.00 inches Distance from Curb Face to Street Crown TCROWN= 22.0 ft Gutter Width W= 2.00 ft Street Transverse Slope Sx= 0.020 ft/ft Gutter Cross Slope(typically 2 inches over 24 inches or 0.083 ft/ft) SW= 0.083 ft/ft Street Longitudinal Slope-Enter 0 for sump condition SO= 0.014 ft/ft Manning's Roughness for Street Section(typically between 0.012 and 0.020) nMEET= 0.016 Minor Storm Major Storm Max.Allowable Spread for Minor&Major Storm TMnx= 18.0 18.0 ft Max.Allowable Depth at Gutter Flowline for Minor&Major Storm d,4m= 6.0 12.0 inches Allow Flow Depth at Street Crown(check box for yes,leave blank for no) r r MINOR STORM Allowable Capacity is based on Spread Criterion Minor Storm Major Storm MAJOR STORM Allowable Capacity is based on Spread Criterion Q,iio„= 14.8 14.8 cfs Minor storm max.allowable capacity GOOD-greater than the design peak flow of 0.02 cfs on sheet'Inlet Management' Major storm max.allowable capacity GOOD-greater than the design peak flow of 1.50 cfs on sheet'Inlet Management' MHFD-Inlet_v5.03.xism,Inlet DP 3e 11/13/2024,1:17 PM INLET ON • • 'AD MYFD-In et, Version.5 ugust Ln i c_ H-Curb H-Vert Wo W Lo(G) Design Information(Input) User-Defined MINOR MAIOR Combination Type of Inlet Type= User-Defined Combination Local Depression(additional to continuous gutter depression'a') aLOCAL= 2.0 inches Total Number of Units in the Inlet(Grate or Curb Opening) No= 2 Length of a Single Unit Inlet(Grate or Curb Opening) L.= 3.00 ft Width of a Unit Grate(cannot be greater than W,Gutter Width) Wo= 2.00 ft Clogging Factor for a Single Unit Grate(typical min.value=0.5) Cf(G)= 0.50 0.50 lClogging Factor for a Single Unit Curb Opening(typical min.value=0.1 C = 0.10 0.10 Street Hydraulics:OK-0<Allowable Street Capacity' MINOR MAIOR Design Discharge for Half of Street(from In/et Management) Q.= 0.0 1.5 cfs Water Spread Width T= 0.7 6.3 ft Water Depth at Flowline(outside of local depression) d= 1.7 3.0 inches Water Depth at Street Crown(or at TM.) dcaowN= 0.0 0.0 inches Ratio of Gutter Flow to Design Flow Eo= 1.000 0.797 Discharge outside the Gutter Section W,carried in Section Tx Q.= 0.0 0.3 cfs Discharge within the Gutter Section W Q.= 0.0 1.2 cfs Discharge Behind the Curb Face QanCK= 0.0 0.0 cfs Flow Area within the Gutter Section W Aw= 0.00 0.34 sq ft Velocity within the Gutter Section W Vw= 0.0 3.5 fps Water Depth for Design Condition d = 3.7 5.0 inches Analysis For Grate Type=CDOT/Denver 13 Valley Grate(Calculated) MINOR MAIOR Total Length of Inlet Grate Opening L= 6.00 6.00 ft Ratio of Grate Flow to Design Flow Eo-oanTe= 1.000 0.797 Under No-Clogging Condition MINOR MAIOR Minimum Velocity Where Grate Splash-Over Begins V.= 2.42 2.42 fps Interception Rate of Frontal Flow Rf= 1.00 0.96 Interception Rate of Side Flow Rx= 0.86 0.55 Interception Capacity Qi= 0.0 1 1.3 cfs Under Clogging Condition MINOR MAIOR Clogging Coefficient for Multiple-unit Grate Inlet GrateCoeff= 1.50 1.50 Clogging Factor for Multiple-unit Grate Inlet GrateClog= 0.38 6.38 Effective(unclogged)Length of Multiple-unit Grate Inlet LQ= 3.75 3.75 ft Minimum Velocity Where Grate Splash-Over Begins V.= 1.83 1.83 fps Interception Rate of Frontal Flow Rf= 1.00 0.91 Interception Rate of Side Flow Rx= 0.67 0.30 Actual Interception Capacity Q,= 0.0 1.2 Cfs Carry-Over Flow= to be applied to curb opening or next d s inlet - 0.0 0.3 Cfs Curb Opening or Slotted Inlet Analysis(Calculated) MINOR MAJOR Equivalent Slope S. SQ= 0.116 0.137 ft/ft Required Length LT to Have 100%Interception LT= 0.00 2.80 ft Under No-Clogging Condition MINOR MAJOR Effective Length of Curb Opening or Slotted Inlet(minimum of L,LT) L= 0.00 2.80 ft Interception Capacity Qi= 0.0 0.2 cfs Under Clogging Condition MINOR MAJOR Clogging Coefficient CurbCoeff= 0.00 1.00 Clogging Factor for Multiple-unit Curb Opening or Slotted Inlet CurbClog= 0.00 0.08 Effective(Unclogged)Length L.= 0.00 2.80 ft Actual Interception Capacity Q.= 0.0 0.2 Cfs Carry-Over Flow= - 0.0 0.1 cfs Summary MINOR MAJOR Total Inlet Interception Capacity Q= 0.0 1.4 cfs Total Inlet Carry-Over Flow(flow bypassing inlet) Qb= 0.0 0.1 cfs Ca ture Percents e= Co/a= 100 92 MHFD-Inlet_v5.03.xism,Inlet DP 3e 11/13/2024,1:17 PM Street Section at Neck down in Polaris Street Iw WorkEheet:Street Sedian-Neckdown at Polaria.5t U'�® 0 n lform Floe; Gradually Varied Flow Measageo Salve For: Dlsdiip£ge v y Friction Method: Manniirtg Formula Roughness Goefriderld d.fl26 Flow Area: 17,4 rt' Channel Slupe. 6.669 fuR Wetted Perimeter: 62.5 R E-H.n: 5,111.6U fl Hydraulic Radius'. 33 in Eleralion Rsnge_ 5,1162-to 5,111 dlfl Top Width 62.07 F Disch.rge: 39.3$ at Normal Depth', 94 In Gritical Depth: 6.6 In Critical Slope: 0.646 fttt Velocity: 227 ffls Velocity Head, 6.p8 ft Specifc Energy: 6_86 R Fronde Number: 6.755 Flow Type'. Slcb[ftW 7 Ed it Sect,do M opt]ons Calculation Successful. Total Flow into the Street is Approx. is 23.5 cfs at dp 6a and 5.1 cfs at 7a. 38.38 cfs Capacity to ROW. 5111.25 r -- 5111.20 -- ---- -- -- ------------ 5111.15 5111.10 5111.05 5111.D0 5110.95 -- --- ------ --- ---------------- --------- ------- 5110.90 5110.85 5110.80 5110.75 5110.70 5110.65 5110.60 w 5110.55 5110.45 s11D.aD 5110.35 5110.30 5110.25 5110.20 5110.15 511D.1D 5110.05 5110.00 ..�................ .............-.._._.._..._._.,...._._.._..._. ._..._...._.. ................. .. ...._...--- ._..--------------- i...- 5109.95 i � ! 0+00 0+15 0+10 0+15 0+20 0+23 0+3D 0+35 0+40 0+45 0+50 0+55 0+6D station Orchard Place - Flow Lines- 100 year event fw ®C-Sec6-North FL ICI ID Uniform Fbw Gradualty Varied Fbw _; Mexsegea LQ print preview Mij Options Salve Far ItFurival0¢pth v ti Frintlon Mehod: Marvring Fdittllds v 5111.30 Roughness Goeftlraent D_016 Flow Area. 169 fl= 5111.20 Ghunnel Slope: g.614 difl Weded Perimeler. T/.2 fl 5111.10 Elevation: 5,11 D68 R Hydraulic Radius: 2.6 In 5111.00 Elevation Renge. 5,11 U.Ytn 5,1111R Top Width: ]7.15 ft - -- --- 5110.90 ❑ischarge. 6B-4D ab Nurmal depth, 58 -In ........_ .._..._.�....__-..____-,r 5110M Gitical Depth: 6T in r -5110.]0- Gnt,mll Slope: D ODS fult - d S1imin Velocity, 4_i➢ Rfs w _ Velocity Head. 026 fl 5110.50 Specific Energy. 8,T4 fl 5110.40 Froude Number; 1545 I 5110.30 Flow Type: :SupercNkal S110.20 5110'10 ---1 - - - ---_I 5110.00 I_. 5tatio 10+40 11+60 10+8 11+00 11+20 11+40 Etlll secdon Options Calculation Successful. w..,amo-sne�.care h«= o C- £3' Ciro kiS ion:Cent,Lii- C_J_ Uniform Flow Gradually Varied Fbw Messages. c'Primtpreview [,1y0ptions SOIre For. Normal DeplM1� ti Frtctlon Method: -;-Jng Fnrmule vj 5112.80 Roughness Cnetfcient D.Ui6 Fi-Nea'. 162 ff 5112.60 Channal Slops D.g14 RIR Wetletl Penmeler: 69.6 R 5112.40 Elevation; 6,111-4T ft Hydraulic Rod- 28 In 5112.20 Devetlan Renge: 5,11gD to 5,1t27ft Top Width: ®55 R 5112.00 Dlschsrgi, 69.40 f� Normal Depth' 6,2 in 511"" G ndcel.."in 7,3 in 5111.50 Gridcel Slope: 0.00.5 � m 5111.40 '' w$111.YD Velocity: 4B tVs - 5111.00 Velocity Head: 029 R ----- - 5110.80 Sperfic En y OrBD R .. .._.___-........ 5110.60 ............. ... Froude Number: 15� ........ . ...____-_____ 5110.40 I FIow TYPe: 5110.20 SupercritlCal -.-. --.•.. _, _- 5110.00 5109.80. 13+00 13+50 14+00 14+50 �IEdlt Section Optiarts statlon 0 Ca6cukfion SuccrsEu[. S-tn Fl C ._ �fr�s5e6en:5ovdA F].. �n" unmrm Flow Gramea9y VeriM Flow �}Messages [q Pdnt Preview '*Options Normal Uepgl v y Fncfibn Melhofl M'annerg Fnrmu� S11Y.40 Roughness Gde imt D.D16 Flaw Area 1].7 tt' S112.20 Channel Slope', 0016 m WeNed Penmeter: St7 ft 1112.00 Elevation', 5,ttp19 R Hybraullc Radius: 26 In 5111.So EJeretion Range: 5,109]fn 5,1122fl Tap WitlN: 6L71 R 5111:fi0 Dischflrge: 71.76 nfs Normal QepN- 8.1 in 5111.40 _,,.,_ Critical Depth: ].0 m 5_.20 Gmlcal 9npe'. opal; fliR -m s1u:DD Vflcdty: 404 tyy w si10:80- VelorRty Hesd: P25 { 511a.60 Specific Energy: D,16 ft 5110.40 i i Fronde Number: 1,S/t1 5110.20 Flow Type: Supercrffinel 5110" s109.80 5109.60 Li Edit Sectlan Option 2+50 3+00 Statio 3+50 4+00 n ®I Calculation Successful, Overflow Swale—Cross Section South of W. Orchard Place t".Ordh-,,dPI.=,:ertic, o O K Uniform Flow Gradually Varied Flaw rdessages Salve For Normal Depth y Friction Method: MaTwungforrnula Roughness Coefficient 6:g34 Flow Area: 23.3 ft' Channel Slope: 4:6t}5 ftfft Wetted Perimeter: 23.0 ft Elevation: 5.110.69 ft Hydraulic Radius: 12:1 in. Elevation Range: 5,109.2 to 5,111.9ft Top Width: 22.69 ft Discharge: 71.79 cfs Normal Depth: 17.5 in Critical Depth: 12.6 in Critical Slope: 10.019 fUft Velocity: 3.08 fVs Velocity Head: 0.15 R. Specific Energy: 1.61 ft Fro ud a Number: 0.537 Flow Type: Suberttieai Edit Section Options Calculation Successful. Cross Section;W.Orchard PI.Overflow c Print Preview Q Options 5112.00 - 5111.60 5111.40 5111.20 5111.00 = 5110.8.0 O 5110.60 I 5110.40 5110.20 5110.00 5109.80 — 5109.60 5109.40 5109.20 - -- - --------------------------- 5109.00 ' 10+00 10+05 10+10 10+15 10+20 10+25 10+30 10+35 Station Urban Drainage and Flood Control District Modeling Hydraulic and Energy Gradients in Storm Sewers: October 6, 2009 6.3 Combined Junction Loss Equation V V2 2 V2 V2 Hi = HS =kbT + —k,, • 1�- ]+kU � =k Equation(13) 2g 2g 2g 2g 2g where, Hj=UD-Sewer junction loss Hs=Standard method junction loss kbT= Bend loss coefficient at truckling kbL= Bend loss coefficient at lateral VtT=Full flow velocity of trunk line at manhole Vj;=Full flow velocity of incoming lateral at manhole Vo=Full flow velocity of trunk line at manhole k=Head Loss Coefficient g=Acceleration due to Gravity Table 2-StormCAD Standard Method Conversions StormCAD Conversion Table Bend Angle K coefficient Conversion 0 0 0.05 -0 22.5 0.1 45 0.4 m 60 0.64 90 1.32 1 Lateral K coefficient Conversion Bend Non Angle Surcharged Surcharged 0 45 0.27 0.47 J 60 0.52 0.9 90 1 1.02 1 1.77 J 2 Laterals K coefficient Conversion 45 0.96 60 1.16 90 1.52 The engineering guidelines from this study provide the methodology needed to reach an HGL analysis result using StormCAD which replicates that of UD-Sewer. However, the following limitations apply: • The full pipe velocity should not exceed 18 fps • The conversion only applies for the storm sewer pipe sizes 42"or less • A regional storm sewer system should use UD-Sewer only Page 19 Scenario: 100 - Year StormCAD 3979701 StormCAD Model.stsw Bentley Systems,Inc. Haestad Methods Solution Center [10.03.02.04] 8/28/2024 27 Siemon Company Drive Suite 200 W Watertown,CT 06795 USA +1-203- Page 1 of 1 755-1666 100 Year Profiles DPOI Profile-1-100-Year TVPe'.manM1ole bats arc . .caber mn M1s�o / m r �� bel/e,nloM1om -, oL a" Ia.as e s,ttl Imp m S,t10 1. 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DPO1B Profile-1-300-Year s itv __ I �_ � — '� •o o� — s.�os x� — s,eos3o — — s.�os A s,.oa sa DP02 Profile-i-100-Y.. m.ss s.ias. -------------- s,sos.on s eos --- ---- lah.i:z.z-is�rvcry coms�rvix-r(sm.ml _ --- rypa'.rianM1ole--- 31o53v -- - s,zos v.o s.v aa.o is.v zo.o zs.v so.o zs.o ao.v as.o so.v �[ron(R)s.o asv xv.o ]s.v ev.o es.o so.o ss.o too.o aos.o vio.v 100 Year Profiles DP03 Profile-1-100-Year f s1os. is(sw�1 �f m woes° ed — T — T T O.o t0.0 z0.° 3o.a Jo.0 50.0 60.0 .0.0 e0.0 900 l00.0 1v0.0 1_0.0 130.a 1VO.0 15°.0 5[aG on](R)a� v90.0 2000 2W.o z_0.0 z30.0 _as.° SO.a z6o.a >]O.o _fl0.o z9o.0 39°.0 31a0 3.°.0 33°.0 3au0 DPO5 Profile-1-100-Year as(st .1(smr) 100 Year Profiles -1-100-Yea r= =jo I 36 �— Page 1 of 1 Scenario: 100-Year Current Time Step:0.000 h FlexTable:Conduit Table Flow Diameter Length Slope Invert Invert Hydraulic Hydraulic Energy Energy Grade Grade Grade Grade Velocity Upstream Structure Label (Unified) (Calculated) (Start) (Stop) (cfs) (in) (ft) Wit) (ft) (ft) Line(In) Line Line(In) Line (fUs) (ft) (Out)(ft) (ft) (Out)(ft) 6.3-GRATE INLET C-6.2(Storm) 1.50 15.0 110.5 -0.005 5,105.01 5,105.51 5,106.09 5,106.04 5,106.20 5,106.07 3.21 6.2 MH(Stone) C-6.1(Storm) 1.50 15.0 81.3 -0,009 5,104.16 5,104.90 5,106.02 5,105.98 5,106.05 5,106.00 4.15 5.2-OUTLET STRUTURE(Storm) C-5.1(Storm) 49.52 42.0 19.8 0.005 5,102.75 5,102.66 5,106.28 5,106.23 5,106.69 5,106.64 5.15 3.2 MH(Stone) C-.3.1(Storm) 9.20 18.0 58.1 -0.008 5,104.01 5,104.46 5,106.43 5,105.98 5,106.85 5,106.40 5.21 C-2.2 Type D Inlet C-2.1(Storm) 38.30 30.0 102.7 -0.005 5,105.26 5,105.77 5,108.43 5,107.35 5,109.38 5,108.53 7.80 1B-GRATE INLET(Storm) C-1B(Storm) 5.10 18.0 9.4 0.005 5,106.49 5,106.44 5,109.48 5,109.46 5,109.61 5,109.59 2.89 1.3A-12"DROP IN NYLOPLASTIC INLET C-A1.2(Storm) 3.50 12.0 54.6 -0,010 5,111.56 5,112.11 5,112.91 5,112.35 5,113.33 5,112.78 5.22 1.2A-Type CInlet C-Al.1(Storm) 3.50 18.0 53.0 0.037 5,110.95 5,109.01 5,111.82 5,111.86 5,111.98 5,111.92 8.53 3.4-Type C Inlet(Storm) C-3.3(Storm) 8.20 18.0 205.7 0.005 5,106.01 5,105.06 5,108.50 5,107.24 5,108.83 5,107.58 4.64 3.3-Type C Inlet(Storm) C-3.2(Storm) 9.20 18.0 75.2 0.005 5,104.96 5,104.56 5,107.22 5,106.65 5,107.64 5,107.07 5.21 2.3-18 INCH DOME INLET(Storm) C-2.2(Storm) 0.00 12.0 7.3 -0.007 5,105.87 5,105.92 5,108.48 5,108.48 5,108.48 5,108.48 0.00 1.10-Type C Inlet C-1.9(Storm) 14.20 24.0 58.3 0.003 5,110.24 5,110.04 5,113.24 5,113.01 5,113.55 5,113.32 4.52 1.9-MH(Storm) C-1.8(Storm) 14.20 24.0 86.9 0.005 5,109.94 5,109.51 5,112.59 5,112.24 5,112.90 5,112.56 4.52 1.8-MH(Storm) C-1.7(Storm) 14.20 24.0 89.1 0,005 5,109.41 5,108.96 5,112.21 5,111.86 5,112.53 5,112.18 4.52 1.7-MH(Storm) C-1.6(Storm) 15.60 24.0 105.2 0.005 5,108.86 5,108.33 5,111.47 5,110.97 5,111.85 5,111.35 4.97 1.6 MH(Stone) C-1.5(Storm) 15.60 24.0 101.8 0,006 5,108.22 5,107.60 5,110.93 5,110.45 5,111.31 5,110.83 4.97 1.5 MH(Storm) C-1.4(Storm) 15.60 24.0 107.1 0.005 5,107.50 5,106.96 5,110.41 5,109.90 5,110.79 5,110.28 4.97 1.4-MH(Storm) C-1.3(Storm) 15.60 24.0 84.5 0.005 5,106.86 5,106.44 5,109.86 5,109.46 5,110.25 5,109.94 4.97 1.3-Shallow Top MH(Storm) C-1.2(Storm) 17.50 24.0 22.5 0.003 5,106.34 5,106.27 5,108.73 5,108.59 5,109.21 5,109.07 5.57 2.2 GRATE INLET Storm C-1.1 Stone 36.20 30.0 27.1 0.003 5,106.17 5,106.09 5,108.55 5,108.13 5,109.42 5,109.24 7.37 X:13970000.all\39797011StormCAD\3979701 StonmCAD Model.stsw file:///C:/Users/WaterR/AppData/Local/TempBentley/StorrnCAD/aunfcuv2.xml 11/25/2024 Page 1 of 1 Scenario: 100 -Year Current Time Step: 0.000 h FlexTable: Manhole Table Elevation Elevation Flow Hydraulic Hydraulic Energy Energy Headloss (Total Grade Grade Grade Grade Headloss Headloss Label (Ground) (Invert) Coefficient (ft) (ft) Out) Line(In) Line Line(In) Line Method (ft) (Standard) (cfs) (ft) (Out)(ft) (ft) (Out)(ft) 1.10-Type CInlet 5,115.69 5,110.24 14.20 5,113.60 5,113.24 5,113.92 5,113.55 Standard 0.37 1.160 1.9-MH(Storm) 5,115.19 5,109.94 14.20 5,113.01 5,112.59 5,113.32 5,112.90 Standard 0.42 1.320 1.8-MH(Storm) 5,114.44 5,109.41 14.20 5,112.24 5,112.21 5,112.56 5,112.53 Standard 0.03 0.100 1.3A-12"DROP IN NYLOPLASTIC INLET 5,114.42 5,112.11 3.50 5,112.93 5,112.91 5,113.35 5,113.33 Standard 0.02 0.050 1.7-MH(Storm) 5,113.62 5,108.86 15.60 5,111.86 5,111.47 5,112.18 5,111.85 Standard 0.39 1.020 1.2A-Type CInlet 5,113.62 5,110.95 3.50 5,111.83 5,111.82 5,112.25 5,111.98 Standard 0.01 0.050 1.6 MH(Storm) 5,112.70 5,108.22 15.60 5,110.97 5,110.93 5,111.35 5,111.31 Standard 0.04 0.100 1.5 MH(Storm) 5,111.78 5,107.50 15.60 5,110.45 5,110.41 5,110.83 5,110.79 Standard 0.04 0.100 1.4-MH(Storm) 5,110.91 5,106.86 15.60 5,109.90 5,109.86 5,110.28 5,110.25 Standard 0.04 0.100 2.2 GRATE INLET(Storm) 5,110.47 5,106.17 36.20 5,108.59 5,108.55 5,109.07 5,109.43 Standard 0.04 0.050 6.2 MH(Storm) 5,110.45 5,104.90 1.50 5,106.04 5,106.02 5,106.07 5,106.05 Standard 0.02 0.640 1.3-Shallow Top MH(Storm) 5,110.31 5,106.34 17.50 5,109.46 5,108.73 5,109.59 5,109.21 Standard 0.73 1.520 3.4-Type C Inlet(Storm) 5,110.08 5,106.01 8.20 5,108.51 5,108.50 5,108.85 5,108.83 Standard 0.02 0.050 1B-GRATE INLET(Storm) 5,110.02 5,106.49 5.10 5,109.49 5,109.48 5,109.62 5,109.61 Standard 0.01 0.050 C-2.2 Type D Inlet 5,109.51 5,105.77 38.30 5,108.48 5,108.43 5,108.48 5,109.38 Standard 0.05 0.050 3.2 MH(Storm) 5,109.04 5,104.46 U0 5,106.65 5,106.43 5,107.07 5,106.85 Standard 0.22 0.520 3.3-Type C Inlet(Storm) 5,108.86 5,104.96 9.20 5,107.24 5,107.22 5,107.58 5,107.64 Standard 0.02 0.050 6.3-GRATE INLET 5,108.56 5,105.51 1.50 5,106.10 5,106.09 5,106.21 5,106.20 Standard 0.01 0.050 2.3-18 INCH DOME INLET(Storm) 5,107.56 5,105.92 0.00 5,107.56 5,107.56 5,107.56 5,107.56 Standard 0.00 0.050 5.2-OUTLET STRUTURE Storm 5,107.54 5,102.75 49.52 1 5,106.30 5,106.28 5,106.71 1 5,106.69 1 Standard 0.02 0.050 X:\3970000.aIR3979701\StormCAD\3979701 StormCAD Model.stsw file:///C:/Users/WaterR/AppData/Local/TempBentley/StonnCAD/snxrg4cw.xml 11/25/2024 2 Year Profiles DPOI P-Mi 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Gail/ y s,o el c (mrm I—n 1.0.1 111.0 31- DP05 Profile-1-2-Year „m =Mtn ,.voE 1121 1,0 3s „ _, 6.1 7 1 1 1 1 , v sa11.,1 .,t, , __ ,3 ,3s ,,° „s ,s s=16",es ,.1 ,.s,sQ I'll ,91 191 , =o=.,I -,_ 2 Year Profiles DP06-Profile-1-2-Year Page 1 of 1 Scenario:2-Year Current Time Step:0.000 h FlexTable:Conduit Table Flow Diameter Length Slope Invert Invert Hydraulic Hydraulic Energy Energy Grade Grade Grade Grade Velocity Upstream Structure Label (Unified) (Calculated)(cfs) (in) (ft) Wit) (ft) (ft) Line(In) Line Line(in) Line (fUs) (ft) (Out)(ft) (ft) (Out)(ft) 6.3-GRATE INLET C-6.2(Storm) 0.02 15.0 110.5 -0.005 5,105.01 5,105.51 5,105.57 5,105.06 5,105.58 5,105.08 0.90 6.2 MH(Stone) C-6.1(Storm) 0.02 15.0 81.3 -0,009 5,104.16 5,104.90 5,104.95 5,104.21 5,104.97 5,104.23 1.15 5.2-OUTLET STRUTURE(Storm) C-5.1(Storm) 18.59 42.0 19.8 0.005 5,102.75 5,102.66 5,104.07 5,103.89 5.104.56 5,104.47 6.22 3.2 MH(Stone) C-.3.1(Storm) 2.00 18.0 58.1 -0.008 5,104.01 5,104.46 5,104.99 5,104.48 5,105.19 5,104.75 4.18 C-2.2 Type D Inlet C-2.1(Storm) 8.80 30.0 102.7 -0.005 5,105.26 5,105.77 5,106.76 5,106.20 5,107.13 5,106.62 5.18 1B-GRATE INLET(Storm) C-1B(Storm) 1.10 18.0 9.4 0.005 5,106.49 5,106.44 5,107.42 5,107.42 5,107.44 5,107.44 3.08 1.3A-12"DROP IN NYLOPLASTIC INLET C-A1.2(Storm) 0.80 12.0 54.6 -0,010 5,111.56 5,112.11 5,112.49 5,111.88 5,112.62 5,112.09 3.68 1.2A-Type CInlet C-Al.1(Storm) 0.80 18.0 53.0 0.037 5,110.95 5,109.01 5,111.28 5,109.75 5,111.40 5,109.77 5.53 3.4-Type C Inlet(Storm) C-3.3(Storm) 1.80 18.0 205.7 0.005 5,106.01 5,105.06 5,106.52 5,105.56 5,106.70 5,105.75 3.37 3.3-Type C Inlet(Storm) C-3.2(Storm) 2,00 18.0 75.2 0.005 5,104.96 5,104.56 5,105.49 5,105.09 5,105.69 5,105.29 3.63 2.3-18 INCH DOME INLET(Storm) C-2.2(Storm) 7.20 12.0 7.3 -0.007 5,105.87 5,105.92 5,107.16 5,106.85 5,108.46 5,108.17 9.17 1.10-Type C Inlet C-1.9(Storm) 3.30 24.0 58.3 0.003 5,110.24 5,110.04 5,110.95 5,110.88 5,111.12 5,110.99 3.50 1.9-MH(Storm) C-1.8(Storm) 3.30 24.0 86.9 0.005 5,109.94 5,109.51 5,1%58 5,110.13 5,110.81 5,110.38 4.01 1.8-MH(Storm) C-1.7(Storm) 3.30 24.0 89.1 0,005 5,109.41 5,108.96 5,110.04 5,109.75 5,110.27 5,109.88 4.01 1.7-MH(Storm) C-1.6(Storm) 3.50 24.0 105.2 0.005 5,108.86 5,108.33 5,109.51 5,108.97 5,109.75 5,109.22 4.08 1.6 MH(Stone) C-1.5(Storm) 3.60 24.0 101.8 0,006 5,108.22 5,107.60 5,108.67 5,108.20 5,109.11 5,108.50 4.38 1.5 MH(Storm) C-1.4.(Storm) 3.50 24.0 107.1 0.005 5,107.50 5,106.96 5,108.15 5,107.59 5,108.39 5,107.85 4.09 1.4-MH(Storm) C-1.3(Storm) 3.50 24.0 84.5 0.005 5,106.86 5,106.44 5,107.51 5,107.42 5,107.75 5,107.50 4.07 1.3-Shallow Top MH(Storm) C-1.2(Storm) 3.90 24.0 22.5 0.003 5,106.34 5,106.27 5,107.22 5,107.20 5,107.36 5,107.32 3.54 2.2 GRATE INLET Storm C-1.1 Storm 8.00 30.0 27.1 0.003 5,106.17 5,106.09 5,107.19 5,107.03 5,107.47 5,107.38 4.16 X:13970000.all\39797011StormCAD\3979701 StormCAD Modelstsw file:///C:/Users/WaterR/AppData/Local/TempBentley/StormCAD/3nhbi2xw.xml 11/25/2024 Page 1 of 1 Scenario: 2 -Year Current Time Step: 0.000 h FlexTable: Manhole Table Elevation Elevation Flow Hydraulic Hydraulic Energy Energy Headloss (Total Grade Grade Grade Grade Headloss Headloss Label (Ground) (Invert) Coefficient (ft) (ft) Out) Line(In) Line Line(In) Line Method (ft) (Standard) (cfs) (ft) (Out)(ft) (ft) (Out)(ft) 1.10-Type CInlet 5,115.69 5,110.24 3.30 5,111.15 5,110.95 5,111.32 5,111.12 Standard 0.20 1.160 1.9-MH(Storm) 5,115.19 5,109.94 3.30 5,110.88 5,110.58 5,110.99 5,110.81 Standard 0.30 1.320 1.8-MH(Storm) 5,114.44 5,109.41 3.30 5,110.06 5,110.04 5,110.31 5,110.27 Standard 0.02 0.100 1.3A-12"DROP IN NYLOPLASTIC INLET 5,114.42 5,112.11 0.80 5,112.49 5,112.49 5,112.63 5,112.62 Standard 0.01 0.050 1.7-MH(Storm) 5,113.62 5,108.86 3.50 5,109.75 5,109.51 5,109.88 5,109.75 Standard 0.24 1.020 1.2A-Type CInlet 5,113.62 5,110.95 0.80 5,111.28 5,111.28 5,111.49 5,111.40 Standard 0.01 0.050 1.6 MH(Storm) 5,112.70 5,108.22 3.50 5,108.90 5,108.87 5,109.16 5,109.11 Standard 0.02 0.100 1.5 MH(Storm) 5,111.78 5,107.50 3.50 5,108.18 5,108.15 5,108.48 5,108.39 Standard 0.02 0.100 1.4-MH(Storm) 5,110.91 5,106.86 3.50 5,107.54 5,107.51 5,107.80 5,107.75 Standard 0.02 0.100 2.2 GRATE INLET(Storm) 5,110.47 5,106.17 8.00 5,107.20 5,107.19 5,107.32 5,107.47 Standard 0.01 0.050 6.2 MH(Storm) 5,110.45 5,104.90 0.02 5,104.97 5,104.95 5,104.98 5,104.97 Standard 0.01 0.640 1.3-Shallow Top MH(Storm) 5,110.31 5,106.34 3.90 5,107.42 5,107.22 5,107.44 5,107.36 Standard 0.20 1.520 3.4-Type C Inlet(Storm) 5,110.08 5,106.01 1.80 5,106.53 5,106.52 5,106.71 5,106.70 Standard 0.01 0.050 1B-GRATE INLET(Storm) 5,110.02 5,106.49 1.10 5,107.42 5,107.42 5,107.44 5,107.44 Standard 0.00 0.050 C-2.2 Type D Inlet 5,109.51 5,105.77 8.80 5,106.78 5,106.76 5,108.10 5,107.13 Standard 0.02 0.050 3.2 MH(Storm) 5,109.04 5,104.46 2.00 5,105.10 5,104.99 5,105.30 5,105.19 Standard 0.10 0.520 3.3-Type C Inlet(Storm) 5,108.86 5,104.96 2.00 5,105.50 5,105.49 5,105.69 5,105.69 Standard 0.01 0.050 6.3-GRATE INLET 5,108.56 5,105.51 0.02 5,105.57 5,105.57 5,105.58 5,105.58 Standard 0.00 0.050 2.3-18 INCH DOME INLET(Storm) 5,107.56 5,105.92 7.20 5,107.22 5,107.16 5,108.53 5,108.46 Standard 0.07 0.050 5.2-OUTLET STRUTURE Storm 5,107.54 5,102.75 18.59 1 5,104.10 1 5,104.07 1 5,104.59 5,104.56 Standard 0.02 0.050 X:\3970000.aIR3979701\StormCAD\3979701 StormCAD Model.stsw file:///C:/Users/WaterR/AppData/Local/TempBentley/StonnCAD/yvuzynnk.xml 11/25/2024 21 APPENDIX D - WATER QUALITY CALCULATIONS WQ Tributary Areas Subdivision: Polestar Project Name: Polestar Location: Fort CoT ink Project No.: 39797.01 Calculated By: ARJ Checked By: Date: 11/13/24 #1-Rain Garden Area Basin (ad %Imp. Al 1.02 15.8% A2 0.58 51.6% A3 0.78 25.3% A4 1.23 65.0%. As 0.42 56.5% A6 1.03 68.7% A7 0.85 63.3% A8 0.58 83.8% A9.1 0.16 84.4% A9.2 0.03 54.5% A10 0.09 84.7% A11 0.13 68.8% Al2 0.26 33.7% A13 0.40 61.0% A14 0.09 21.1% A15 0.49 23.5% A16 0.12 51.1% A17 0.43 29.6%. A18 0.72 45.8% A19 0.35 51.5% Total 9.75 50.3% WQCV Drain Time(hr): 12 Coefficient,a(Figure 3.2): 0.8 WQCV(in): 0.17 WQCV(ac-ft): 0.13 X:\3970000.all\3979701\Excel\Drainage\3979701 Drainage_Calcs_Tepfate_v2.07.xL- Pagel of8 2/10/2025 WQ Tributary Areas Subdivision: Polestar Project Name: Polestar Location: Fort Co Project No.: 39797.01 Calculated By: ARJ Checked By: Date:337i3J£� #2-Rain Garden Area Basin (ac) %Imp. B1 1.23 49.89/ B2 0.31 77.79/. Total 1.55 55.5% WQCV Drain Time(hr): 12 Coefficient,a(Figure 3.2): 0.8 WQCV(in): 0.18 WQCV(ac-ft): 0.02 X:\3970000.all\3979701\Excel\Drainage\3979701 Drainage_Calcs_Tepfate_v2.07.xlsm Page2of8 2/10/2025 WQ Tributary Areas Subdivision: Polestar Project Name: Polestar Location: Fort C6 ins Project No.: 39797.01 Calculated By: ARJ Checked By: Date:337i3J£T- #3-Rain Garden Area Basin (ac) %Imp. C1 0.28 47.0% C2 0.32 30.5% D8 0.19 90.5% D7 0.11 85.5% Total 0.90 55.0% WQCV Drain Time(hr): 12 Coefficient,a(Figure 3.2): 0.8 WQCV(in): 0.18 WQCV(ac-ft): 0.01 X:\3970000.a11\3979701\Excel\Dainage\3979701 Drainage_Calcs_Tepfate_v2.07.xlsm Page3of8 2/10/2025 WQ Tributary Areas Subdivision: Polestar Project Name: Polestar Location: Fortes iTins Project No.: 39797.01 Calculated By: ARJ Checked By: Date:337i37£4- #4-Rain Garden Area Basin (ac) %Imp. D6 0.28 60.5% Total 0.28 60.5% WQCV Drain Time(hr): 12 Coefficient,a(Figure 3.2): 0.8 WQCV(in): 0.19 WQCV(ac-ft): 0.004 X:\3970000.all\3979701\Excel\Drainage\3979701 Drainage_Calcs_Tepfate_v2.07A— Page4of8 2/10/2025 WQ Tributary Areas Subdivision: Polestar Project Name: Polestar Location: Fogs Project No.: 39797.01 Calculated By: AR1 Checked By: Date:337i37£� #5-Rain Garden Area Basin (ac) %Imp. D5 0.29 67.3% D4 0.25 60.9% Total 1 0.54 WQCV Drain Time(hr): 12 Coefficient,a(Figure 3.2): 0.8 WQCV(in): 0.20 WQCV(ac-ft): 0.01 X:\3970000.a11\3979701\Excel\Dainage\3979701 Drainage_Calcs_Tepfate_v2.07A— Page5.0 2/10/2025 WQ Tributary Areas Subdivision: Polestar Project Name: Polestar Location: Fort Project No.: 39797.01 Calculated By: ARJ Checked By: Date:337i3J£� #6-Rain Garden Area Basin (ac) %Imp. D3 0.16 69.8% D2 0.22 62.9% D1 0.35 64.1% Total 0.73 65.0% WQCV Drain Time(hr): 12 Coefficient,a(Figure 3.2): 0.8 WQCV(in): 0.20 WQCV(ac-ft): 0.01 X:\3970000.all\3979701\Excel\D,,C,age\3979701 Drainage_Calcs_Tepfate_v2.07A— Page6.0 2/10/2025 Table 5.4-1.Drain Time Coefficients for WQCV Calculations Drain Time(hm) Coefficient(a) 12 0.8 40 1.0 Reference:The UD-BMP excel-based spreadsheet,RG and EDB tabs may be used to aid it calculating WQCV. Figure 5.4-1 WQCV Based on BMP Drain Time O.s00 0.4 40 hour i time 50 i o� 0.400 � � 24.hour drain time � c 0.350 WQCV=a(0.91P-1.19RW.781) i 0,300 12-hrdmin time a=0.8 y 0.250 24-hr dns time a 0.9 40-hr drain time a=1.0 3 0:200 c > 0.150 U 12 flour drain time C) 0.100 3 0 osa Of 0 D00 0 0.1 D.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Total Imperviousness Ratio(i=la/1OO) Once the WQCV in watershed inches is found from Figure 3.2-12 or using Equation 3.2-1,the required BMP volume in acre-feet can be calculated as follows: Once the WQCV in watershed inches is found from Figure 3.2-12 or using Equation 3.2-1.the required BMP volume in acre-feet can be calculated as follows; V=CM.K�Ax1.2 Equation 7.2 Where:V=required volume,acre-ft A=tributary catchment area upstream,acres WQCV=Water Quality Capture Volume,watershed inches 1.2=to account for the additional 20%of required storage for sedimentation accumulation X:\3970000.all\3979701\Excel\Drainage\3979701 Drainage_Calcs_Template_v2.07.xlsm Page7o0 2/10/2025 WQ Pond Tributary Areas Subdivision: Polestar Project Name: Polestar Location: Fort CoF inT s Project No.: 39797.01 Calculated By: ARJ Checked By: Date:337i37£� WATER QUALITY IN DETENTION POND Area Basin (ac) %Imp. Fl 3.92 31.2% E1 2.24 41.1% E2 0.54 54.2% E3 0.31 59.0% O51 0.61 15.2% 052 0.09 50.8% 17W 10.20 45.0% Total 17.92 41.0% This table shows the WQ on-site treated in the Polestar WQCV Drain Time(hr): 40 Detention pond.This calculation includes 20% Coefficient,a(Figure 3.2): 1.0 contingency for sediment accumulation as shown in WQCV(in): 0.18 equaltion 7-2.PLEASE NOTE area on MHFD sheet was WQCV(ac-ft): 0.33 multiplied by 1.2 to account for this. X:\3970000.all\3979701\Excel\Drainage\3979701 Drainage_Cales_T—Plate_v2.07.xlsm Pagegdli 2/10/2025 STAGE-STORAGEDETENTION BASIN MHFD-Detention,Version 4.06(July 2022) Project:Polestar Basin ID:Rain Garden#1 nce5 oRmcE Depth Increment= 0.50 R Optional optional POOL Example Zone Configuration(Retention Pond) Stage-Storage Stage Override Length Width Area Override Area Volume Volume Descri Hon ft stageR ft ft ft� Area ft' acre R' ac-ft Watershed Information Media Surface — 0.00 — — — 3,022 0.069 Selected BMP Type= RG — 0.50 — — — 3,962 0.091 1,746 0.040 Watershed Area= 9.75 acres — 1.00 — — — 5,067 0.116 4,003 0.092 Watershed Length= 750 ft — 1.50 — — — 5,855 0.134 6,734 0.155 Watershed Length to.Centroid= 450 It — 2.00 — — — 6,658 0.153 9,862 0.226 Watershed Slope= 0.010 ft/ft — 2.50 — — — 7,637 0.175 13,436 0.308 Watershed Imperviousness= 50.30% percent — 3.00 — — — 8,660 0.199 17,510 0.402 Percentage Hydrologic Soil Group A= 0.0% percent — 3.50 — — — 9,728 0.223 22,107 0.508 Percentage Hydrologic Soil Group B= 10.0% percent — 4.00 — — -- 10,840 0.249 27,249 0.626 Percentage Hydrologic$oil Groups C,/D= percent — 4.50 — — — 12,108 0.278 32,986 0.757 Target WQCV Drain Time= 12.0 hours — — — — Locatlon for l-hr Rainfall Depths=User Input -- — — -- After providing required inputs above including 1-hour rainfall dalift,dick'Run CUHP'to generate runoff hydrograplss using — — —the embedded Colorado Urban Hydrograph Procedure. Optional User Overrides — — — — Water Quality Capture Volume(WQCV)= 0.135 acre4eet —feet -- — — — Excess Urban Ruroff Volume(EURV)= 0.470 acre-feet acre-feet -- — — -- 2-yr Runoff Volume(P1=0.82 In.)= 0.296 acre-feet 0.82 inches — — — — 5-yr Runoff Volume(PI=1.09 in.)= 0.444 ac-feet inches — — — — 10-yr Runoff Volume(P1=1.4In.)= 0.665 acre-feet 1.40 inches -- -- — -- 25-yr Runoff Volume(Pi.=1.69 in.)= 0.933acre-feet inches — — — — 50-yr Ruroff Volume(PI=1.99 in.)= 1.174acre-feet inches — — — — 10D-yr Ruroff Volume(P1=2.86 in.)= 1.928 —feet 186 inches — — — — 500-yrRuroR Volume(PI=3.14 in.)= 1163acre-feet inches — — — — Approximate 2-yr Detention Volume= 0.281 acre-feet — — — — Approximate 5-yr Detention Volume= 0.438 acre-feet — — — — Appoadmatel0-yr Detention Volume= 0.558acre-feet — — —Approximate25-yr Detention Volume= 0.636 acre-feet — — — — Approximate 5D-yr Detention Volume= 0.693acre-feet — — — — Approximate 100-yr Detention Volume= 1.008acre-feet — — — — Define Zones and Basin Geometry — — — — Zone 1 Volume(WQCV)= 0.135 acre-feet — — — — Zone 2 Volume(User Defined-Zone 1)= 0.000 cre-feet Total detention — — — — lone 3 Volume(User Defined-Zones 1&2)= 0.000 ac-feet volume is less than — — — — Total Detention Basin Volume= 0.135 acre-feet 100-year volume. Initial Surcharge Volume(ISV)= N/A R' — — — — Initial Surcharge Depth(ISD)= N/A ft — — — — Total Available Detemion Depth(1-6�i)= user ft — — — — Depth of Trickle Channel(Hrc)= N/A It — — — — SI, of Trickle Clwnnol(Src)= N/A ft/R — — — — Slopes of Main Basin SIdeS(Sic)= user H:V — — — — Basin Length-to-Width Ratio(R�)= user — — — — Initial Surcharge Area(Assv)= user ft' — — — — Surcharge Volume Length(LgV)= ft — — — — Surcharge Volume Width(Wsv)= user ft Depth or Basin Floor(HF=R)= user I, — — — — Length of Basin Floor(L,_,)= user ft -- -- — -- Width of Basin Floor(WFrmR)= user ft — — — — Area of Basin Floor(A—R)= user ft' — — — — Volume of Basin Floor(V—R)= user ft' -- -- — -- Depth of Main Basin(Homo)= user it — — — — Length of Main Basin(LmAr,) user ft — — — — Wldth of Main Basin(WMAjO= user ft — — — — Area of Main Basin(Annm)= user ft' — — — — Volume of Main Basin(Vm )= user ft' — — — — Calculated Total Basin Volume(V—)= unr acre-feet — — — — MHFD,Deft ndon W-06-Rain Garden.xism,Basin 11/25/2024,10:52 AM STAGE-STORAGEDETENTION BASIN MHFD-Detention,Version 4.06(July 2022) z0 4aa 15 930o a? �4 5 3100 0 0 0.00 1.w 3.p0 4.50 6.00 wage lR) —Length(ft) —Width(ft) —A-(S.k) 01— 0.7W o.no o.5w e yK 0.140 0:383 v d ; 0.070 O.J. 0-o o 0.000 0.00 1.50 3Ao 4.50 6.00 Sdge IR.1 —Area lac.es� —Volume lac-k� MHFDOe on W-06-Rai,Garden.xlsm,Basin 11/25/2024,10:52 AM DETENTIONBASIN OUTLET MHFD-Detention, Version 4.06(July 1011) Project:Polestar Basin ID:Rain Garden#1 -!ZONES Estimated Estimated 2II -ZONE i Stage(ft) Volume(ac-ft) Outlet Type va- E EOP1I'^O� � Zone 1(WQCV) 1.35 0.135 Filtration Media adrr.N Zone 2(User) 1.35 0.000 Weir&Pipe(Restrict) oxeas.-E arnww oaincEs Zone 3(User) 1.35 0.000 lWeir&Pipe(Restrict) Example Zone Configuration(Retention Pond) Total(all zones) 0.135 User Input:Orifice at Underdrain Outlet(typically used to drain WQCV in a Filtration BMP) Calculated Parameters for Underdrain Underdrain Orifice Invert Depth= 2.30 ft(distance below the filtration media surface Underdrain Orifice Area= 0.0 ftz P ) Underdrain Orifice Diameter= 1.75 inches Underdrain Orifice Centroid= 0.07 feet User Input: Orifice Plate with one or more orifices or Elliptical Slot Weir(typically used to drain WQCV and/or EURV in a sedimentation BMP) Calculated Parameters for Plate Centroid of Lowest Orifice= N/A ft(relative to basin bottom at Stage=0 ft) WQ Orifice Area per Row=MN/A ft' Depth at top of Zone using Orifice Plate= N/A ft(relative to basin bottom at Stage=0 ft) Elliptical He = feet Orifice Plate:Orifice Vertical Spacing= N/A inches Elliptical Slot Centroid= feet Orifice Plate:Orifice Area per Row= N/A sq.inches Elliptical Slot Area= fe User Input: Stage and Total Area of Each Orifice Row(numbered from lowest to highest) Row 1(optional) Row 2(optional) Row 3(optional) Row 4(optional) Row 5(optional) Row 6(optional) Row 7(optional) Row 8(optional) Stage of Orifice Centroid(ft) N/A N/A N/A N/A N/A N/A N/A N/A Orifice Area(sq.inches) N/A N/A N/A N/A N/A N/A N/A N/A Row 9(optional) Row 10(optional) Row 11 optional Row 12(optional) Row 13(optional) Row 14(optional) Row 15(optional) Row 16(optional) Stage of Orifice Centroid(it) N/A N/A N/A N/A N/A N/A N/A N/A Orifice Area(sq.inches) N/A N/A N/A N/A N/A N/A N/A N/A User Input: Vertical Orifice(Circular or Rectangular) Calculated Parameters for Vertical Orifice Not Selected Not Selected Not Selected Not Selected Invert of Vertical Orifice= N/A N/A ft(relative to basin bottom at Stage=0 ft) Vertical Orifice Area= N/A N/A ft Depth at top of Zone using Vertical Orifice= N/A N/A ft(relative to basin bottom at Stage=0 ft) Vertical Orifice Centroid= N/A N/A feet Vertical Orifice Diameter= N/A N/A inches User Input: Overflow Weir(Droobox with Flat or Sloped Grate and Outlet Pioe OR Rectangular/Trapezoidal Weir and No Outlet Pipe) Calculated Parameters for Overflow Weir Zone 2 Weir Zone 3 Weir Zone 2 Weir Zone 3 Weir Overflow Weir Front Edge Height,Ho= 1.36 2.13 ft(relative to basin bottom at Stage=o ft) Height of Grate Upper Edge,Ht= 1.36 2.86 feet Overflow Weir Front Edge Length= 3.140 4.13 feet Overflow Weir Slope Length= 0.00 3.01 feet Overflow Weir Grate Slope= 0.00 4.00 H:V Grate Open Area/100-yr Orifice Area= 0.00 2.00 Horiz.Length of Weir Sides= 0.00 2.92 feet Overflow Grate Open Area w/o Debris= 0.00 9.81 ft, Overflow Grate Type= Close Mesh Grate Close Mesh Grate Overflow Grate Open Area w/Debris= 0.00 9.81 fe Debris Clogging%=1 0% T 0% 1 a/o User Input:Outlet Pipe w/Flow Restriction Plate(Circular Orifice.Restrictor Plate,or Rectangular Orifice) Calculated Parameters for Outlet Pipe w/Flow Restriction Plate Zone 2 Restrictor Zone 3 Restrictor Zone 2 Restrictor Zone 3 Restrictor Depth to Invert of Outlet Pipe= 0.08 0.14 ft(distance below basin bottom at Stage=o ft) Outlet Orifice Area= 0.79 4.91 ft2 Outlet Pipe Diameter= 12.00 30.00 inches Outlet Orifice Centroid= 0.50 1.25 feet Restrictor Plate Height Above Pipe Invert= 12.00 30.00 inches Half-Central Angle of Restrictor Plate on Pipe= 3.14 3.14 radians User Input:Emergency Spillway(Rectangular or Trapezoidal) Calculated Parameters for Spillway Spillway Invert Star ft(relative to basin bottom at Stage=0 ft) Spillway Design Flow Depth= feet Spillway Crest Length= feet Stage at Top of Freeboard= feet Spillway End Slopes= H:V Basin Area at Top of Freeboard= acres Freeboard above Max Water Surface= feet Basin Volume at Top of Freeboard= acre-ft Routed Hydro rah Results The user can override the default CUHP hydro roc hs and runoff volumes by entering new values in the Inf/ow H dro roc hs table Co/umns W throw h AF. Design Storm Return Period= 2 Year 25 Year 50 Year 100 Year 500 Year One-Hour Rainfall Depth(in)= N/A N/A 0.82 1.09 1.40 1.69 1.99 2.86 3.14 CUHP Runoff Volume(acre-ft)= 0.135 0.470 0.296 0.444 0.665 0.933 1.174 1.928 2.163 Inflow Hydrograph Volume(acre-ft)= N/A N/A 0.296 0.444 0.665 0.933 1.174 1.928 2.163 CUHP Predevelopment Peak Q(cfs)= N/A N/A 0.1 0.8 2.8 6.1 8.4 16.0 18.3 OPTIONAL Override Predevelopment Peak Q(cfs)= N/A N/A Predevelopment Unit Peak Flow,q(cfs/acre)= N/A N/A 0.01 0.08 0.29 0.63 0.87 1.65 1.88 Peak Inflow Q(cfs)= N/A N/A 4.4 6.7 10.2 14.7 18.6 30.4 34.0 Peak Outflow Q(cfs)= 0.2 19.3 1.6 3.4 5.2 10.4 14.2 26.3 29.9 Ratio Peak Outflow to Predevelopment Q= N/A N/A N/A 4.5 1.9 1.7 1.7 1.6 1.6 Structure Controlling Flow= Overflow Weir 1 Overflow Weir 2 Overflow Weir 1 Overflow Weir 1 Overflow Weir 2 Overflow Weir 2 Overflow Weir 2 Overflow Weir 2 verflow Weir Max Velocity through Grate 1(fps)= N/A N/A N/A N/A N/A N/A N/A N/A N/A Max Velocity through Grate 2(fps)= N/A 2.37 N/A N/A 0.0 0.5 0.8 2.0 2.4 Time to Drain 97%of Inflow Volume(hours)= 12 12 14 14 13 13 12 10 9 Time to Drain 99%of Inflow Volume(hours)= 12 13 15 15 15 14 14 14 13 Maximum Ponding Depth(ft)= 1.36 3.33 1.64 1.85 2.20 2.63 2.81 3.23 3.34 Area at Maximum Ponding Depth(acres)= 0.13 0.21 0.14 0.15 0.16 0.18 0.19 0.21 0.21 Maximum Volume Stored(acre-ft)= 0.136 0.470 1 0.174 0.202 1 0.256 0.332 0.365 0.449 0.470 MHFD-Detention_v4-06-Rain Garden.xlsm,Outlet Structure 2110/2025,10:59 AM DETENTIONOUTLET MHFD Detention Version 4.06(July 1011 40 —SODVR IN .....S00YROUT 35 —1OOYR IN 100YR OUT —50YRIN 30 50YR OUT �25YR IN 25YR OUT 25 10YR IN IOYR OUT —SYR IN .SYR OUT 3 20. �2YR IN O 2YROUT AEU RV IN 1S — •EURV OUT �WqN IN .....Wo OUT 10 5 v 0 0.1 1 10 TIME]hr] 4 —500YR �100YR 3.5 —SoyR —25YR �IOYR 3 —5YR —2YR �EURV 2.5 —WQCV x x r a 0 2 z oe S z 0 rl 1.5 1 I 0.5 0 _LL 0.1 1 10 100 DRAIN TIME[hr] 30,000 30 O User Area[ft^2] —Interpolated Area[ft^2] 25,000 ••-0' Summary Area[W2] 25 —Volume[ft^3] ...i••Summary Volume[W3] 20,000 —Outflow[cfsj 20 •••0••Summary Outflow[cfs] x 15,000 15 0 O j O x 10,000 10 Z 5,000 5 .......... 0 0 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 PONDING DEPTH[ft] S-A-V-D Chart Axis Override. X-axis Left Y-Axis Rig ht Y-Axis minimum bound maximum bound MHFD-Detention_v4-06-Rain Garden.xlsm,Outlet Structure 2110/2025,10:59 AM DETENTIONBASIN OUTLET MHFD-Detention, Version 4.06(July 1011) Summary Stage-Area-Volume-Discharge Relationships The user can create a summary S-A-V-D by entering the desired stage increments and the remainder of the table will populate automatically. The user should graphically compare the summary S-A-V-D table to the full S-A-V-D table in the chart to confirm it captures all key transition points. Stage Area Area Volume Volume Total Stage-Storage Stage Description [R] [R'] [acres] [R'] Jac-R] [crs] Media Surface-5106.00 0.00 3,022 0.069 0 0.000 0.00 For best results,include the 5106.5 0.50 3,962 0.091 1,746 0.040 0.13 stages of all grade slope 5107 1.00 5,067 0.116 4,003 0.092 0.14 changes(e.g.ISV and Floor) from the S-A-V table on 5107.5 1.50 5,855 0.134 6,734 0.155 0.65 Sheet'Basin'. 5107.55-WQCV 1.55 5,936 0.136 7,029 0.161 0.94 5108 2.00 6,658 0.153 9,862 0.226 4.75 Also include the inverts of all 5108.5 2.50 7,637 0.175 13,436 0,308 8.24 outlets(e.g.vertical orifice, 5109 3.00 8,660 0.199 17,510 0.402 19,06 overflow grate,and spillway, 5109.5 3.50 9,728 0.223 22,107 0.508 35.95 where applicable). 5109.53-100 YR 3.53 9,794 0.225 22,400 0.514 36.77 5110.0 4.00 10,840 0.249 27,249 0.626 40.18 5110.25 4.25 11,474 0.263 30,038 0.690 41.88 5110.5 4.50 12,108 0.278 32,986 0.757 43.52 MHFD-Detention_v4-06-Rain Garden.xlsm,Outlet Structure 2110/2025,10:59 AM Design Procedure Form: Rain Garden(RG) UD-BMP(Version 3.07,March 2018) Sheet 1 of 2 Designer: ARJ Company: JR Engineering Date: August 22,2024 Project: Polestar Location: #2-Rain Garden;B1-132 1.Basin Storage Volume A)Effective Imperviousness of Tributary Area,la la= 55.5 % (100%if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio(i=Ia1100) i= 0.555 C) Water Quality Capture Volume(WQCV)for a 12-hour Drain Time WQCV= 0.18 watershed inches (WQCV=0.8*(0.91*i3-1.19*i2+0.78*i) D) Contributing Watershed Area(including rain garden area) Area= 67,518 sq ft E) Water Quality Capture Volume(WQCV)Design Volume VwOG,=0cu ft Vol=(WQCV/12)*Area F) For Watersheds Outside of the Denver Region,Depth of de= 0.43 in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VWOCV OTHER= cu ft Water Quality Capture Volume(WQCV)Design Volume H) User Input of Water Quality Capture Volume(WQCV)Design Volume VwncvuSER= 1,199 cu ft (Only if a different WQCV Design Volume is desired) 2.Basin Geometry A)WQCV Depth(12-inch maximum) DwOcv= 7.5 in B)Rain Garden Side Slopes(Z=4 min.,horiz.dist per unit vertical) Z= 4.00 ft/ft (Use"0"if rain garden has vertical walls) C)Mimimum Flat Surface Area AM;,,= 749 sq ft D)Actual Flat Surface Area AA"1 d= 870 sq ft E)Area at Design Depth(Top Surface Area) AT,= 3143 sq ft F)Rain Garden Total Volume VT= 1,254 cu ft (VT=((ATop+AAO w)/2)*Depth) 3.Growing Media Choose One 18"Rain Garden Growing Media p Other(Explain): 4.Underdrain System Choose One A)Are underdrains provided? #YES p NO B)Underdrain system orifice diameter for 12 hour drain time i)Distance From Lowest Elevation of the Storage y= 2.3 ft Volume to the Center of the Orifice ii)Volume to Drain in 12 Hours V0112= 1,199 cu ft iii)Orifice Diameter,3/8"Minimum Do= 3/4 in No.2 UD BMP_v3.07.xlsm,RG 8/22/2024,3:58 PM Design Procedure Form: Rain Garden (RG) Sheet 2 of 2 Designer: ARJ Company: JR Engineering Date: August 22,2024 Project: Polestar Location: #2-Rain Garden;B1-B2 5.Impermeable Geomembrane Liner and Geotextile Separator Fabric Choose One O YES A) Is an impermeable liner provided due to proximity O NO of structures or groundwater contamination? 6.Inlet/Outlet Control Choose One O Sheet Flow-No Energy Dissipation Required A) Inlet Control Q Concentrated Flow-Energy Dissipation Provided Choose One 7.Vegetation Q Seed(Plan for frequent weed control) O Plantings O Sand Grown or Other High Infiltration Sod 8. Irrigation Choose One O YES A) Will the rain garden be irrigated? 0 NO Notes: No.2 LID BMP_v3.07.xlsm,RG 8/22/2024,3:58 PM Design Procedure Form: Rain Garden(RG) UD-BMP(Version 3.07,March 2018) Sheet 1 of 2 Designer: ARJ Company: JR Engineering Date: February 10,2025 Project: Polestar Village Location: Rain Garden No.3;Basins CI-C2 and D8 1.Basin Storage Volume A)Effective Imperviousness of Tributary Area,la la= 55.0 % (100%if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio(i=la/100) i= 0.550 C) Water Quality Capture Volume(WQCV)for a 12-hour Drain Time WQCV= 0.18 watershed inches (WQCV=0.8*(0.91*i3-1.19*i2+0.78*i) D) Contributing Watershed Area(including rain garden area) Area= 39,204 sq ft E) Water Quality Capture Volume(WQCV)Design Volume VwOG,=0cu ft Vol=(WQCV/12)*Area F) For Watersheds Outside of the Denver Region,Depth of de= 0.43 in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VWOCV OTHER= cu ft Water Quality Capture Volume(WQCV)Design Volume H) User Input of Water Quality Capture Volume(WQCV)Design Volume VwncvuSER= 576 cu ft (Only if a different WQCV Design Volume is desired) 2.Basin Geometry A)WQCV Depth(12-inch maximum) DwOcv= 6.8 in B)Rain Garden Side Slopes(Z=4 min.,horiz.dist per unit vertical) Z= 4.00 ft/ft (Use"0"if rain garden has vertical walls) C)Mimimum Flat Surface Area AM;,,= 431 sq ft D)Actual Flat Surface Area AA"1 d= 507 sq ft E)Area at Design Depth(Top Surface Area) AT,= 1527 sq ft F)Rain Garden Total Volume VT= 576 cu ft (VT=((ATpp+AAO w)/2)*Depth) 3.Growing Media Choose One 18"Rain Garden Growing Media p Other(Explain): 4.Underdrain System Choose One A)Are underdrains provided? #YES p NO B)Underdrain system orifice diameter for 12 hour drain time i)Distance From Lowest Elevation of the Storage y= 2.3 ft Volume to the Center of the Orifice ii)Volume to Drain in 12 Hours V0112= 576 cu ft iii)Orifice Diameter,3/8"Minimum Do= 9/16 in No.3 UD BMP_v3.07.xlsm,RG 2/10/2025,10:38 AM Design Procedure Form: Rain Garden (RG) Sheet 2 of 2 Designer: ARJ Company: JR Engineering Date: February 10,2025 Project: Polestar Village Location: Rain Garden No.3;Basins Cl-C2 and D8 5.Impermeable Geomembrane Liner and Geotextile Separator Fabric Choose One O YES A) Is an impermeable liner provided due to proximity O NO of structures or groundwater contamination? 6.Inlet/Outlet Control Choose One O Sheet Flow-No Energy Dissipation Required A) Inlet Control Q Concentrated Flow-Energy Dissipation Provided Choose One 7.Vegetation Q Seed(Plan for frequent weed control) O Plantings O Sand Grown or Other High Infiltration Sod 8. Irrigation Choose One O YES A) Will the rain garden be irrigated? 0 NO Notes: No.3 LID BMP_v3.07.xlsm,RG 2/10/2025,10:38 AM Design Procedure Form: Rain Garden(RG) UD-BMP(Version 3.07,March 2018) Sheet 1 of 2 Designer: ARJ Company: JR Engineering Date: August 22,2024 Project: Polestar Village Location: Rain Garden No.4;Basins D6 1.Basin Storage Volume A)Effective Imperviousness of Tributary Area,la la= 60.5 % (100%if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio(i=la/100) i= 0.605 C) Water Quality Capture Volume(WQCV)for a 12-hour Drain Time WQCV= 0.19 watershed inches (WQCV=0.8*(0.91*i3-1.19*i2+0.78*i) D) Contributing Watershed Area(including rain garden area) Area= 12,197 sq ft E) Water Quality Capture Volume(WQCV)Design Volume Vwo�v=0cu ft Vol=(WQCV/12)*Area F) For Watersheds Outside of the Denver Region,Depth of de= 0.43 in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VwocV OTHER= cu ft Water Quality Capture Volume(WQCV)Design Volume H) User Input of Water Quality Capture Volume(WQCV)Design Volume VwncvUSER= 193 cu ft (Only if a different WQCV Design Volume is desired) 2.Basin Geometry A)WQCV Depth(12-inch maximum) DwOcv= 7.5 in B)Rain Garden Side Slopes(Z=4 min.,horiz.dist per unit vertical) Z= 4.00 ft/ft (Use"0"if rain garden has vertical walls) C)Mimimum Flat Surface Area AM;,,= 148 sq ft D)Actual Flat Surface Area AA"1 d= 177 sq ft E)Area at Design Depth(Top Surface Area) AT,= 475 sq ft F)Rain Garden Total Volume VT= 204 cu ft (VT=((ATpp+AAO w)/2)*Depth) 3.Growing Media Choose One 18"Rain Garden Growing Media p Other(Explain): 4.Underdrain System Choose One A)Are underdrains provided? #YES p NO B)Underdrain system orifice diameter for 12 hour drain time i)Distance From Lowest Elevation of the Storage y= 2.3 ft Volume to the Center of the Orifice ii)Volume to Drain in 12 Hours V0112= 193 cu ft iii)Orifice Diameter,3/8"Minimum DO= 5/16 In LESS THAN MINIMUM. USE DIAMETER OF 3/8" No.4 UD BMP_v3.07.xlsm,RG 8/22/2024,4:33 PM Design Procedure Form: Rain Garden (RG) Sheet 2 of 2 Designer: ARJ Company: JR Engineering Date: August 22,2024 Project: Polestar Village Location: Rain Garden No.4;Basins D6 5.Impermeable Geomembrane Liner and Geotextile Separator Fabric Choose One O YES A) Is an impermeable liner provided due to proximity O NO of structures or groundwater contamination? 6.Inlet/Outlet Control Choose One O Sheet Flow-No Energy Dissipation Required A) Inlet Control Q Concentrated Flow-Energy Dissipation Provided Choose One 7.Vegetation Q Seed(Plan for frequent weed control) O Plantings O Sand Grown or Other High Infiltration Sod 8. Irrigation Choose One O YES A) Will the rain garden be irrigated? 0 NO Notes: No.4 LID BMP_v3.07.xlsm,RG 8/22/2024,4:33 PM Design Procedure Form: Rain Garden(RG) UD-BMP(Version 3.07,March 2018) Sheet 1 of 2 Designer: ARJ Company: JR Engineering Date: August 22,2024 Project: Polestar Village Location: Rain Garden No.5;Basins D4 1.Basin Storage Volume A)Effective Imperviousness of Tributary Area,la la= 64.3 % (100%if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio(i=la/100) i= 0.643 C) Water Quality Capture Volume(WQCV)for a 12-hour Drain Time WQCV= 0.20 watershed inches (WQCV=0.8*(0.91*i3-1.19*i2+0.78*i) D) Contributing Watershed Area(including rain garden area) Area= 23,522 sq ft E) Water Quality Capture Volume(WQCV)Design Volume Vwo�v=0cu ft Vol=(WQCV/12)*Area F) For Watersheds Outside of the Denver Region,Depth of de= 0.43 in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VwOCV OTHER= cu ft Water Quality Capture Volume(WQCV)Design Volume H) User Input of Water Quality Capture Volume(WQCV)Design Volume VwncvuSER= 394 cu ft (Only if a different WQCV Design Volume is desired) 2.Basin Geometry A)WQCV Depth(12-inch maximum) DwOcv= 9.5 in B)Rain Garden Side Slopes(Z=4 min.,horiz.dist per unit vertical) Z= 4.00 ft/ft (Use"0"if rain garden has vertical walls) C)Mimimum Flat Surface Area AM;,,= 302 sq ft D)Actual Flat Surface Area AA"1 d= 309 sq ft E)Area at Design Depth(Top Surface Area) AT,= 742 sq ft F)Rain Garden Total Volume VT= 416 cu ft (VT=((ATpp+AAO w)/2)*Depth) 3.Growing Media Choose One 18"Rain Garden Growing Media p Other(Explain): 4.Underdrain System Choose One A)Are underdrains provided? #YES p NO B)Underdrain system orifice diameter for 12 hour drain time i)Distance From Lowest Elevation of the Storage y= 2.33 ft Volume to the Center of the Orifice ii)Volume to Drain in 12 Hours V0112= 394 cu ft iii)Orifice Diameter,3/8"Minimum Do= 7/16 in No.5 UD BMP_v3.07.xlsm,RG 8/22/2024,4:37 PM Design Procedure Form: Rain Garden (RG) Sheet 2 of 2 Designer: ARJ Company: JR Engineering Date: August 22,2024 Project: Polestar Village Location: Rain Garden No.5;Basins D4 5.Impermeable Geomembrane Liner and Geotextile Separator Fabric Choose One O YES A) Is an impermeable liner provided due to proximity O NO of structures or groundwater contamination? 6.Inlet/Outlet Control Choose One O Sheet Flow-No Energy Dissipation Required A) Inlet Control Q Concentrated Flow-Energy Dissipation Provided Choose One 7.Vegetation Q Seed(Plan for frequent weed control) O Plantings O Sand Grown or Other High Infiltration Sod 8. Irrigation Choose One O YES A) Will the rain garden be irrigated? 0 NO Notes: No.5 LID BMP_v3.07.xlsm,RG 8/22/2024,4:37 PM Design Procedure Form: Rain Garden(RG) UD-BMP(Version 3.07,March 2018) Sheet 1 of 2 Designer: ARJ Company: JR Engineering Date: August 22,2024 Project: Polestar Village Location: Rain Garden No.6;Basins D1-D3 1.Basin Storage Volume A)Effective Imperviousness of Tributary Area,la la= 65.0 % (100%if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio(i=Ia1100) i= 0.650 C) Water Quality Capture Volume(WQCV)for a 12-hour Drain Time WQCV= 0.20 watershed inches (WQCV=0.8*(0.91*i3-1.19*i2+0.78*i) D) Contributing Watershed Area(including rain garden area) Area= 31,799 sq ft E) Water Quality Capture Volume(WQCV)Design Volume VWQ v=0cu ft Vol=(WQCV/12)*Area F) For Watersheds Outside of the Denver Region,Depth of de= 0.43 in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VWOCV OTHER= cu ft Water Quality Capture Volume(WQCV)Design Volume H) User Input of Water Quality Capture Volume(WQCV)Design Volume VwncvuSER= 539 cu ft (Only if a different WQCV Design Volume is desired) 2.Basin Geometry A)WQCV Depth(12-inch maximum) DwOcv=®in B)Rain Garden Side Slopes(Z=4 min.,horiz.dist per unit vertical) Z= 4.00 ft/ft (Use"0"if rain garden has vertical walls) C)Mimimum Flat Surface Area AM;,,= 413 sq ft D)Actual Flat Surface Area AA"1 d= 430 sq ft E)Area at Design Depth(Top Surface Area) AT,= 1283 sq ft F)Rain Garden Total Volume VT= 571 cu ft (VT=((ATpp+AAO w)/2)*Depth) 3.Growing Media Choose One 18"Rain Garden Growing Media p Other(Explain): 4.Underdrain System Choose One A)Are underdrains provided? #YES p NO B)Underdrain system orifice diameter for 12 hour drain time i)Distance From Lowest Elevation of the Storage y=F 2.3 ft Volume to the Center of the Orifice ii)Volume to Drain in 12 Hours V0112= 539 cu ft iii)Orifice Diameter,3/8"Minimum Do= 1l2 in No.6 UD BMP_v3.07.xlsm,RG 8/22/2024,4:41 PM Design Procedure Form: Rain Garden (RG) Sheet 2 of 2 Designer: ARJ Company: JR Engineering Date: August 22,2024 Project: Polestar Village Location: Rain Garden No.6;Basins D1-D3 5.Impermeable Geomembrane Liner and Geotextile Separator Fabric Choose One O YES A) Is an impermeable liner provided due to proximity O NO of structures or groundwater contamination? 6.Inlet/Outlet Control Choose One O Sheet Flow-No Energy Dissipation Required A) Inlet Control Q Concentrated Flow-Energy Dissipation Provided Choose One 7.Vegetation Q Seed(Plan for frequent weed control) O Plantings O Sand Grown or Other High Infiltration Sod 8. Irrigation Choose One O YES A) Will the rain garden be irrigated? 0 NO Notes: No.6 LID BMP_v3.07.xlsm,RG 8/22/2024,4:41 PM 22 APPEN D I X E - REFERENCES Appendix J Hydrology Appendix J-1 Vicinity Map W MULBERRY ST 1 � o I J I = I I H uiQ a > v ORCHARD PL co Z cl) W J J J > °' m O co Y W ELIZABETH ST I I I I ------- _-- \1 I I J i i I I 1 1 � I I W PROSPECT RD \ VICINITY MAP SCALE: 1"=1000' VICINITY MAP 1000 500 0 1000 2000 POLESTAR VILLAGE JOB NO. 3979701 ORIGINAL SCALE: 1" = 1000' 6-5-2022 SHEET 1 OF 1 A Westrian Company Centennial%3-740-M•Colorado�ft 719-593-M Fat Com 97&491-90•www7 ineeri Can Appendix J-2 Calculations and Exhibits SWMM INPUTS Subdivision:Polestar Project Name: Polestar Location:Fort Collins Project No.:39797.01 Calculated By: ARJ Checked By: Date: 2/7/23 2014 SWMM -100yr Canal Importation Hydrology Update Basin inputs City of Fort Collins Default Inputs City of Fort Collins Horton inputs Tributary Area Width L=A/W Slope %Impery N-Impery N-Pery Store Imperv. Dstore perv. Zero%imperv. Storage(max) Storage(min) Decay Rate Sub-basin 17 25.5 3968.00 279.93 1.00% 45.0% 0.016 0.11 0.1 0.31 25 0.51 0.5 6.48 15 30.0 4356.00 300.00 2.00% 25.0% 0.016 o.11 0.11 0.31 25 0.51 0.5 6.48 Note:Only these two basin in the existing Hydrology were modified. Note:City of Fort Collins 2018 Criteria Recommends 1 for Zero%imperv.In the existing SWMM model this was 25. Note:City of Fort Collins 2018 Criteria Recommends 0.25 for N-Perv.In the existing SWMM model this mas 0.1. Existing SWMM INPUTS Basin inputs City of Fort Collins Default Inputs City of Fort Collins Horton inputs Tributary Area Width L=A/W Slope %Impery N-Impery N-Pery Store Imperv. Dstare perv. Zero%imperv. Storage(max) Storage(min) Decay Rate Sub-basin EP 21.5 1205.33 777.00 1.64% 3.7% 0.016 0.25 0.1 0.3 1 0.51 0.5 6.48 17W 10.2 1481.04 300.00 0.60% 45.0% 0.016 0.25 0.1 0.3 1 0.51 0.5 6.48 17E 24.8 2148.96 300.00 1.33% 45.0% 0.016 0.25 0.1 0.3 1 0.51 0.5 6.48 15E 9.0 1306.80 300.00 1.19% 45.0% 0.016 0.25 0.1 0.3 1 0.51 0.5 6.48 Proposed SWMM INPUTS Basin inputs City of Fort Collins Default Inputs City of Fort Collins Horton inputs Tributary Area Width L=A/W Slope %Impery N-Impery N-Pery Store Imperv. Dstore perv. Zero%imperv. Storage(max) Storage(min) Decay Rate Sub-basin P 21.5 1572.48 595.58 0.86% 50.0% 0.016 0.25 0.1 0.3 1 0.51 0.5 6.48 17W 10.2 1481.04 300.00 0.60% 45.0% 0.016 0.25 0.1 0.3 1 0.51 0.5 6.48 17E 14.8 2148.96 300.00 1.33% 45.0% 0.016 0.25 0.1 0.3 1 0.51 0.5 6.48 15E 9.0 1306.80 300.00 1.19% 45.0% 0.016 0.25 0.1 0.3 1 0.51 0.5 6.48 Ultimate SWMM INPUTS Basin inputs City of Fort Collins Default Inputs City of Fort Collins Horton inputs Tributary Area Width L=A/W Slope %Impery N-Impery N-Pery Store Imperv. Dstore perv. Zero%imperv. Storage(max) Storage(min) Decay Rate Sub-basin P 21.5 1572.48 595.58 0.86% 50.0% 0.016 0.25 0.1 0.3 1 0.51 0.5 6.48 17W 10.2 1481.04 300.00 0.60% 45.0% 0.016 0.25 0.1 0.3 1 0.51 0.5 6.48 17E 14.8 2148.96 300.00 1.33% 45.0% 0.016 0.25 0.1 0.3 1 0.51 0.5 6.48 15E 9.0 1306.80 300.00 1.19% 45.0% 0.016 0.25 0.1 0.3 1 0.51 0.5 6.48 X:\3970000.all\3979701\Exoel\DminsgeU979701 Drainage_Cales_Template_v2.07.xlsm Page 1 of 2/9/2023 REQUIRED POLESTAR DETENTION POND VOLUME The onsite detention for the site i.e. the required runoff difference between the 100 year developed inflow rate and the 2-year historic runoff is 4.88 Acre-ft. In the SWMM model. P - 100 year developed inflow 1.61*106 Gallons of total runoff EP - 2-year existing inflow 0.02*106Gallons of total runoff (1.61*106- 0.02*106) gallons ( 1 ft3 )* ( 1 acre _ 4.88 Acre-ft. 7.4805gallons 43,560 f t3 Time vs. Runoff 140 120 100 — Ln LL 80 °C: 2 Year Existing(Basin EP) n 60 cc 100 Year Developed(Basin P) 40 20 0 0:00:00 1:12:00 2:24:00 3:36:00 4:48:00 6:00:00 7:12:00 8:24:00 Time P- Peak Runoff—119.98 CFS EP -2 Year Peak Runoff—2.31 CFS 65 31 J2 2J 26 4,2 21 26 1.61.4 Io OB 06 Proposed Polestar Pond Drain time PROPOSED -WATER QUALITY FOR POLESTAR DETENTION POND WQ Pond Tributary Areas Subdivision: Polestar Project Name: Polestar Location: Fort CoF inT s Project No.: 39797.01 Calculated By: ARJ Checked By: Date:337i37£� WATER QUALITY IN DETENTION POND Area Basin (ac) %Imp. Fl 3.92 31.2% E1 2.24 41.1% E2 0.54 54.2% E3 0.31 59.0% O51 0.61 15.2% 052 0.09 50.8% 17W 10.20 45.0% Total 17.92 41.0% This table shows the WQ on-site treated in the Polestar WQCV Drain Time(hr): 40 Detention pond.This calculation includes 20% Coefficient,a(Figure 3.2): 1.0 contingency for sediment accumulation as shown in WQCV(in): 0.18 equaltion 7-2.PLEASE NOTE area on MHFD sheet was WQCV(ac-ft): 0.33 multiplied by 1.2 to account for this. X:\3970000.all\3979701\Excel\Drainage\3979701 Drainage_Cales_T—Plate_v2.07.xlsm Pagegdli 2/10/2025 Table 5.4-1.Drain Time Coefficients for WQCV Calculations Drain Time(hrs) Coefficient(a) 12 0.8 40 1.0 Reference:The UD-BMP excel-based spreadsheet,RG and EDB tabs may be used to aid h calculating WQCV. Figure 5.4-1 WQCV Based on BMP Drain Time 0.500 0450 40 hour drain time . i I y 0.400 X_ 24 hour drain time c 0.350 -p WQCV=a(0.91i3-1.19F-+O.780 op at 0.300 w 12-hr drain time a=0.8 � y 0250 24-hr drain time a=0.9 —40 2 40-h r dra in time a=1.0 - 0.200 C 0.150 12 hour drain time 0.100 0.050 ' 0.000 0 0.1 0.2 0.3 0.4 0:5 0.6 0.7 0.8 0.9 1 Total Imperviousness Ratio(i=la/10O) Once the WQCV in watershed inches is found from Figure 3.2-12 or using Equation 3.2-1,the required BMP volume in acre-feet can be calculated as follows: Once the WQCV in watershed inches is found from Figure 3.2-12 or using Equation 3.2-1,the required BMP volume in acre-feet can be calculated as follows: V= 0!21�Axl.2 Equation 7-2 Where:V=required volume,acre-ft A-tributary catchment area upstream,acres WQCV s Water Quality Capture Volume,watershed inches 1.2=to account for the additional 20%of required storage for sedimentation accumulation X:\3970000.all\3979701\Excel\Drainage\3979701 Drainage_Calcs_Template_v2.07.xlsm Page I of 1 8/7/2023 PROPOSED POLESTAR DETENTION POND W ORCHARD PL — • - --- - --- - ------- — I I - - — - - - '7 o 5105 \ r POLESTAR DETENTION POND 3 A3c A3c A3 A3 A3 A3c A3c A3 100 YEAR WSELV 5108.89 - NAVD 88 _ _\ \ / I VOLUME 9.57 ACRE-FT lilt— r r i \� N. a) i it W `C0' � —I —I I *\ \ l PROPOSED GRADING POLESTAR \\ ,. \�� %f �? \ �� r � �-- — — _ —_— _— —I d ✓/ JOB NO. 3979701 11/15/2024 SHEET 1 OF 1 60 30 0 60 J.R ENGOMMIXING A Westrian Company ORIGINAL SCALE: 1" = 60' Can ra 303-7 -cdorAo Wq 719-�20 Fort coins 910-491-M•WWW STAGE-STORAGEDETENTION BASIN MHFD-Detention,Version 4.06(July 1011) Project:Polestar-Interim Detention Pond(PLEASE NOTE:THE AREA ON THIS MHFD SHEET WAS MULTIPLIED BY 1.2 TO ACCOUNT FOR SEDIMENTATION FOR WQCV) Basin ID: J F10E5 onmce De mIncrement= 1.00 R Optional pti0re POo' Example Zone Configuration(Retention Pond) Stage-Storage Stage Override Length Width Area Override Area Volume Volume Description ft stage R ft ft ft2 Area R� acre R' ac fit Watershed Information Top of Mlcropool - 0.00 - - - 66 0.002 Selected BMP Type= EDB 5103 - 0.19 - - - 382 0.009 43 0.001 Watershed Area= 21.50 acres 5104 - 1.19 - - - 20,275 0.465 10,371 0.238 Watershed Length= 1,149 R 5105 - 2.19 - - - 59,591 1.368 50,303 1.155 Watershed Length to.Centroid= 689 It 5106 - 3.19 - - - 87,449 2.008 123,823 2.843 Watershed Slope= 0.011 Rift 5107 - 4.19 - - - 99,692 2.289 217,394 4.991 Watershed Imperviousness= 41.ODti percent 5108 - 5.19 - - - 106,050 2.435 320,265 7.352 Percentage Hydrologic Soil Group A= 0.0% percent 5109 - 6.19 - - - 112,486 1582 429,533 9.861 Percentage Hydrologic$oil Group B= 34.0% percent 5110 - 7.19 - - -- 119,103 2.734 545,328 12.519 Percentage Hydrologic$oil Groups percent - - - - Target WQCV Drain Time= 40.0 hours - - - - Locatlon for 1-hr Rainfall Depths=User Input -- - - -- After providing required inputs above including 1-hour rainfall - - - depths,dick'Run CUHP'to generate runoff hydrograplss using - - -the embedded Colorado Urban Hydrogmph Procedure. Optional User Overrides - - - - Water Quality Capture Volume(WQCV)= 0.327 -feet acre4eat -- - - - Excess Urban Runoff Volume(EURV)= 0.857 acre-feet acre-feet -- - - -- 2-yr Runoff Volume(P1=0.82 In.)= 0.521 acre-feet 0.82 inches - - - - 5-yr Ruroff Volume(PI=1.09 in.)= 0.792 -feet inches - - - - 10-yrRuroff Volume(P1=1.4In.)= 1.246 acre-feet 1A0 inches -- -- - -- 25-yr Ruroff Volume(P'1.=1.69 in.)= 1.863acre-feet inches - - - - 5&yr Runoff Volume(PI=1.99 in.)= 2.388 acnfeet inches - - - - 100-yr Runoff Volume(P1=2.86 in.)= 4.070 -feet 2.86 inches - - - - 500-yr Runoff Volume(P1=3.14 in.)= 4.594 -feet inches - - - - Approximate 2-yr Detention Volume= 0.487 acre-feet - - - - Approximate 5-yr Detention Volume= 0.770 ac-feet - - - - Approximatel0-yr Detention Volume= 1.029acre-feet - - -Approximate25-yr Detention Volume= 1.199 acre-feet - - - - Approximate 5D-yr Detention Volume= 1.309acre-feet - - -Approximate100-yr Detention Volume= 1.951 acnfeet - - - - Set Zone 1 as WQLV - - - - Define Zones and Basin Geometry - - - - Zone I Volume(WQCV)= 0.33 acre-feet - ser - - - Zone 2 Volume(U Defined-Zone 1)= 0.00 cre-feet - - - - Zone 3 Volume(10D-year-Zones 1&2)= 1.62acre-feet - - - - TotalDetentionBasinVolume= 1.95 acre-feet - - - - Initial Surcharge Volume(ISV)= user ft' - - - - Initial Surcharge Depth(ISD)= ft - - - - Total Available Detemion Depth(1­6�i)= user R - - - - Depth of Trickle Channel(Hrc)= user R - - - - Slope of Trickle Clwnrel(STIC= user ft/ft - - - - Slopes of Main Basin SIdeS(Sic)= user H:V - - - - Bmin Length-to-Width Ratio(R�)= user - - - - Initial Surcharge Area(Assv)= user R' - - - - Surcharge Volume Length(Lsv)= ft - - - - Surcharge Volume Width(Wsv)= user R _ Depth or Basin Floor(HFMR)= user ft - - - - Length of Basin Floor(L,_,)= user ft -- -- - -- Width of Basin Floor(WFMR)= user it - - -Area of Basin Floor(Al-R)= user ft' - - - - Volume of Basin Floor(y-R)= user ft' -- -- - -- Depth of Main Basin(Hmnw)= user ft - - - - Length of Main Basin(Lmm user R - - - - Width of Main Basin(Wmm = user R - - - - Area of Main Basin(Amnm)= user ft' - - - - Volume of Main Basin(VM,n = user ft' - - - - Calculated Total Basin Volume(V[opi)= user acne-feet - - - - MHFD.Dm,rlion_v406-Interim Pond.*m,Basin Ilfl42024,10:01 AM STAGE-STORAGEDETENTION BASIN MHFD-Detention,Version 4.06(July 2022) 20 119200 16 swo d g;10 sesaa a� x 2 s Z9g00 o 0 0.00 2.00 4.00 6.00 Uo Stage)R) —Length(ft) —Width(R) —Area(sq.k) 2.7. 11620 2056 9:390 C yyM 1.320 - 6.2fi0 v d ; O.fi&6 3.13t1 0.000 0.000 0.00 2.00 4.00 6.00 8.00 Rw lR.) —Area lages� —Volume lac-kl MHF0.O tention_W-W-Interim Poi .klsm,Basin IVW2024,10:01 AM DETENTIONBASIN OUTLET MHFD-Detention, Version 4.06(July 2022) Project:Polestar-Interim Detention Pond(PLEASE NOTE:THE AREA ON THIS MHFD SHEET WAS MULTIPLIED BY 1.2 TO ACCOUNT FOR SEDIMENTATION FOR WQCV) Basin ID: zaxea mex Estimated Estimated oxc, Stage(ft) Volume(ac-ft) Outlet Type -...-... ranrx wv 'one 1(WQCV) 1.36 0.327 Orifice Plate 01 Zone 2(User) 1.36 0.000 Orifice Plate zow1NAx omrWE Paxuxexr omncEs le 3(100-year) 2.71 1.624 Weir&Pipe(Restrict) Example Zone Configuration(Retention Total(all zones) 1.951 User Input:Orifice at Underdrain Outlet(typically used to drain WQCV in a Filtration BMP) Calculated Parameters for Underdrain Underdrain Orifice Invert Depth=1 N/A ft(distance below the filtration media surface) Underdrain Orifice Area=1 N/A ftz Underdrain Orifice Diameter= N/A inches Underdrain Orifice Centroid= NJA feet User Input: Orifice Plate with one or more orifices or Elliptical Slot Weir(typically used to drain WOCV and/or EURV in a sedimentation BMP) Calculated Parameters for Plate Centroid of Lowest Orifice= W176 ft(relative to basin bottom at Stage=0 ft) WQ Orifice Area per Row= 1.222E-02 fe Depth at top of Zone using Orifice Plate= ft(relative to basin bottom at Stage=0 ft) Elliptical Half-Width= N/A feet Orifice Plate:Orifice Vertical Spacing= inches Elliptical Slot Centroid= N/A feet Orifice Plate:Orifice Area per Row= sq.inches(diameter=1-1/2 inches) Elliptical Slot Area= N/A ft, User Input: Stage and Total Area of Each Orifice Row(numbered from lowest to highest) Row 1(required) Row 2(optional) Row 3(optional) Row (optional) JRow 5(optional) Row 6(optional) Row 7(optional) Row 8(optional) Stage of Orifice Centroid(ft) 0.00 0.45 0.91 Orifice Area(sq.inches) 1.76 1.76 1.76 Row 9(optional) Row 10(optional) Row 11(optional) Row 12(optional) ow 13(optional Row 14(optional) Row 15(optional)Row 16 optional Stage of Orifice Centroid(ft) Orifice Area(sq.inches) User Input: Vertical Orifice(Circular or Rectangular) Calculated Parameters for Vertical Orifice Not Selected Not Selected Not Selected Not Selected Invert of Vertical Orifice= N/A ft(relative to basin bottom at Stage=0 ft) Vertical Orifice Area= N/A ft Depth at top of Zone using Vertical Orifice= N/A ft(relative to basin bottom at Stage=0 ft) Vertical Orifice Centroid= N/A feet Vertical Orifice Diameter= N/A inches User Input: Overflow Weir(Droobox with Flat or Sloped Grate and Outlet Pipe OR Rectangular/Trapezoicial Weir and No Outlet Pipe) Calculated Parameters for Overflow Weir Zone 3 Weir Not Selected Zone 3 Weir Not Selected Overflow Weir Front Edge Height,Ho= 1.36 N/A ft(relative to basin bottom at Stage=0 ft)leight of Grate Upper Edge,H,= 4.98 N/A feet Overflow Weir Front Edge Length= 5.00 N/A feet Overflow Weir Slope Length= 16.40 N/A feet Overflow Weir Grate Slope= 4.42 N/A H:V Grate Open Area/100-yr Orifice Area= 12.63 N/A Horiz.Length of Weir Sides= 16.00 N/A feet Overflow Grate Open Area w/o Debris= 57.09 N/A ft Overflow Grate Type= Type C Grate N/A Overflow Grate Open Area w/Debris= 57.09 N/A ft2 Debris Clogging%=1 0% N/A % User Input:Outlet Pipe w/Flow Restriction Plate(Circular Orifice,Restrior Plate,or Rectangular Orifice) Calculated Parameters for Outlet Pipe w/Flow Restriction Plate Zone 3 Restrior Not Selected Zone 3 Restricto Not Selected Depth to Invert of Outlet Pipe= 0.08 N/A ft(distance below basin bottom at Stage=0 ft) Outlet Orifice Area= 4.52 N/A ft Outlet Pipe Diameter= 42.00 N/A inches Outlet Orifice Centroid= 0.96 N/A feet Restror Plate Height Above Pipe Invert= 20.00 inches Half-Central Angle of Restror Plate on Pipe= 1.52 N/A radians User Input:Emergency Spillway or Trapezoidal) Calculated Parameters for Spillway Spillway Invert Stage 4.98 ft(relative to basin bottom at Stage=0 ft) Spillway Design Flow Depth= 0.26 feet Spillway Crest Length feet Stage at Top of Freeboard= 5.74 feet Spillway End Slopes= 2.50 H:V Basin Area at Top of Freeboard= 2.52 acres Freeboard above Max Water Surface= 0.50 feet Basin Volume at Top of Freeboard= 8.71 acre-ft Routed Hydro rah Results The user can override the default CUHP h dro ra hs and runoff volumes 17y enterino,new values in the Inflow H dro ra hs table Columns W throw h AF. Design Storm Return Period= 2 Year 5 Year 10 Year 25 Year 50 Yea 100 Year 500 Year One-Hour Rainfall Depth(in)= N/A N/A 0.82 1.09 1.40 1.69 1.99 2.86 3.14 CUHP Runoff Volume(acre-ft)= 0.327 0.857 0.521 0.792 1.246 1.863 2.388 4.070 4.594 Inflow Hydrograph Volume(acre-ft)= N/A N/A 0.521 0.792 1.246 1.863 2.388 4.070 4.594 CUHP Predevelopment Peak Q(cfs)= N/A N/A 0.2 1.2 5.4 12.8 17.9 34.2 39.2 PTIONAL Override Predevelopment Peak Q(cfs)= N/A N/A Predevelopment Unit Peak How,q(cfs/acre)= N/A N/A 0.01 0.05 0.25 0.60 0.83 1.59 1.82 Peak Inflow Q(cfs)= N/A N/A 6.6 10.3 17.1 26.7 34.1 56.9 64.0 Peak Outflow Q(cfs)= 0.2 6.1 0.9 2.3 5.2 10.3 14.5 29.5 30.6 Ratio Peak Outflow to Predevelopment Q= N/A N/A N/A 2.0 1.0 0.8 0.8 0.9 0.8 Structure Controlling Flow= Overflow Weir 1 Overflow Weir 1 Overflow Weir 1 Overflow Weir 1 verfiow Weir I Overflow Weir 1 Overflow Weir 1 Outlet Plate 1 Outlet Plate 1 Max Velocity through Grate 1(fps)= N/A 0.11 0.01 0.0 0.1 0.2 0.2 0.5 0.5 Max Velocity through Grate 2(fps)= N/A N/A N/A N/A N/A N/A N/A N/A N/A Time to Drain 97%of Inflow Volume(hours)= 38 39 42 41 39 36 34 27 25 Time to Drain 99%of Inflow Volume(hours)= 40 44 46 46 45 43 42 39 38 Maximum Ponding Depth(it)= 1.36 1.96 1.52 1.68 1.89 2.13 2.29 2.71 2.86 Area at Maximum Ponding Depth(acres)= 0.62 1 1.16 1 0.75 1 0.91 1 109 1,31 1.43 1.70 1.79 Maximum Volume Stored(acre-ft)= 0.330 0.864 0.433 0.574 0.774 1.074 1.295 1 1.953 2.197 MHFD-Detention_v4-06-Interim Pond.xlsm,Outlet Structure 11/14/2024,10:55 AM DETENTIONOUTLET MHFD Detention, Version 4.06(July 1011) 70 —SOOYR IN .....500YR OUT 1ODYR IN 60 100YROUT —SOYR IN 5UYR OUT 50 25YR IN 25YR OUT �10YR IN ———10YR OUT 40 -SYR IN .....SYR OUT 30 �2YR IN 2YROur EURV IN -EURV OU WQCV IN 20 .....WQCV OUT 10 0.1 1 TIME[hr] 3.5 —SWYR —100YR —50YR 3 25YR �IOYR —5YR 2.5 —2YR EURV 00, W4CV x 2 H <1 2 Z 1.5 O 00, 1 0.5 0. )YM 0.1 1 10 DRAIN TIME.[hr] O User Area[ft^2] 350,000 _Interpolated Area.[ft^21 1 •�••Summary Area[ft^21 300,000 -Volume[ft^3] 1 ... ••Summary Volume 1ft^31 Outflow[cfsl 250;000 ...*--Summary Outflow[cfs] 8, T .L m 200,000 O 6 150,000 '00'Z 4: 4 Q 100,000 50,000 2 0 a 0.00 1.00 2.00 3.00 4.00 5.00 6(Ob PONDING DEPTH[ft] S-A-V-D Chart Axis Override. X-axis Left Y-Axis Right Y-Axis minimum bound maximum bound MHFD-Detention_v4-O6-Interim Pond.xlsm,Outlet Structure 11/14/2024,10:55 AM DETENTIONBASIN OUTLET Outflow Hydrograph Workbook Filename.• Inflow Hydrographs The user can override the calculated inflow hydrographs from this workbook with inflow hydrographs developed in a separate program. SOURCE CUHP CUHP CUHP CUHP CUHP CUHP CUHP CUHP CUHP terval TIME WQCV[cfs] EURV[cfs] 2 Year[cfs] 5 Year[cfs] 10 Year[cfs] 25 Year[cfs] 50 Year[cfs] 100 Year[cfs] 500 Year[cfs] min 0:00:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0:05:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0:10:00 o.00 0.00 0.00 0.00 0.00 0.00 0.00 0.20 0.36 0:15:00 0.00 0.00 0.24 0.78 1.31 0.91 1.33 2.05 2.38 0:20:00 0.00 0.00 2.01 3.04 4.16 2.76 3.50 5.38 6.31 0:25:00 0.00 0.00 4.92 7.77 12.47 6.82 8.89 16.78 20.12 0:30:00 o.0o 0.00 6.65 10.33 17.09 20.67 27.33 45.21 51.38 0:35:00 0.00 0.00 6.58 10.17 16.60 26.22 33.86 56.88 64.02 0:40:00 0.00 0.00 6.14 9.29 15.11 26.72 34.12 56.70 63.68 0:45:00 0.00 0.00 5.46 8.33 13.57 24.83 31.66 53.75 60.30 0:50:00 0.00 0.00 4.88 7.58 12.07 22.96 29.23 49.58 55.64 0:55:00 0.00 0.00 4.41 6.80 10.76 20.36 26.02 45.10 50.62 1:00:00 0.00 0.00 3.95 6.05 9.55 17.95 23.03 41.07 46.08 1:05:00 0.00 0.00 3.56 5.40 8.46 15.83 20.37 37.33 41.89 1:10:00 0.00 0.00 3.16 4.96 7.77 13.43 17.32 31.66 35.65 1:15:00 0.00 0.00 2.87 4.54 7.30 11.74 15.19 27.31 30.83 10 1:20:00 0.00 0.00 2.63 4.12 6.66 10.20 13.19 23.14 26.12 1:25:00 0.00 0.00 2.41 3.73 5.85 8.87 11.44 19.47 21.97 1:30:00 0.00 0.00 2.20 3.36 5.09 7.56 9.70 16.30 18.38 1:35:00 0.00 0.00 1.98 3.00 4.37 6.36 8.10 13.40 15.10 1:40:00 0.0o 0.00 1.78 2.56 3.71 5.24 6.62 10.74 12.09 1:45:00 0.00 0.00 1.59 2.17 3.14 4.21 5.27 8.37 9.43 1:50:00 0.00 0.00 1.47 1.91 2.79 3.32 4.14 6.52 7.38 1:55:00 0.00 0.00 1.30 1.75 2.56 2.81 3.49 5.40 6.13 2:00:00 0.00 0.00 1.16 1.61 2.33 2.50 3.09 4.67 5.31 2:05:00 0.00 0.00 0.94 1.31 1.89 1.97 2.42 3.59 4.09 2:10:00 0.00 0.00 0.75 1.04 1.50 1.51 1.86 2.69 3.07 2:15:00 0.00 0.00 0.60 0.82 1.18 1.17 1.44 2.00 2.29 2:20:00 0.00 0.00 0.48 0.65 0.92 0.90 1.10 1.47 1.68 2:25:00 0.00 0.00 0.38 0.51 0.71 0.69 0.83 1.09 1.25 2:30:00 0.00 0.00 0.29 0.39 0.54 0.53 0.63 0.83 0.94 2:35:00 0.00 0.00 0.23 0.30 0.41 0.40 0.47 0.62 0.71 2:40:00 0.00 0.00 0.18 0.23 0.31 0.30 0.36 0.48 0.54 2:45:00 0.00 0.00 0.14 0.17 0.24 0.23 0.27 0.37 0.42 2:50:00 0.00 0.00 0.10 0.13 0.18 0.17 0.21 0.28 0.31 2:55:00 0.00 0.00 0.07 0.09 0.12 0.12 0.15 0.19 0.22 3:00:00 0.0o 0.00 0.05 0.06 0.08 0.08 0.10 0.13 0.15 3:05:00 0.00 0.00 0.03 0.04 0.05 0.05 0.06 0.08 0.08 3:10:00 0.00 0.00 0.01 0.02 0.02 0.02 0.03 0.04 0.04 3:15:00 0.00 0.00 0.01 0.01 0.01 0.01 0.01 0.01 0.01 100 3:20:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3:25:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3:30:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3:35:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3:40:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 -20 3:45:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3:50:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3:55:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 .00 4:00:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4:05:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4:10:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4:15:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 '0 4:20:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 .i 4:25:00 0.00 0.00 0.00 1 0.00 0.00 0.00 0.00 0.00 0.00 0 4:30:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0 F 4:35:00 U0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0 4:40:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4:45:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4:50:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ,0 4:55:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5:00:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5:05:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5:10:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ,O 5:15:00 0.00 0.00K0,00 00 0.00 0.00 0.00 0.00 0.00 5:20:00 0.00 0.00 .00 0.00 0.00 0.00 0.00 0.00 5:25:00 0.00 0.00 .00 0.00 0.00 0.00 0.00 0.00 5:30:00 0.00 0.00 .00 0.00 0.00 0.00 0.00 0.00 i 5:35:00 0.00 0.00 .00 0.00 0.00 0.00 0.00 0.00 5:40:00 0.00 0.00 .00 0.00 0.00 0.00 0.00 0.00 5:45:00 0.00 0.00 .00 0.00 0.00 0.00 0.00 0.00 5:50:00 0.00 0.00 .00 0.00 0.00 0.00 0.00 0.00 5:55:00 0.00 0.00 .00 0.00 0.00 0.00 0.00 0.00 6:00:00 0.00 0.00 0.00 0.00 0.00 0.00 OAO 0.00 0.00 MHFD-Detention_v4-06-Interim Pond.xlsm,Outlet Structure 11/14/2024,10:55 AM DETENTIONBASIN OUTLET MHFD-Detention, Version 4.06(July 1011) Summary Stage-Area-Volume-Discharge Relationships The user can create a summary S-A-V-D by entering the desired stage increments and the remainder of the table will populate automatically. The user should graphically compare the summary S-A-V-D table to the full S-A-V-D table in the chart to confirm it captures all key transition points. Stage Area Area Volume Volume Total Stage-Storage Stage Description [ft] [R'j [acres] [R'] [ac-ftj [crs] For best results,include the stages of all grade slope changes(e.g.ISV and Floor) from the S-A-V table on Sheet'Basin'. Also include the inverts of all outlets(e.g.vertical orifice, overflow grate,and spillway, where applicable). MHFD-Detention_v4-06-Interim Pond.xlsm,Outlet Structure 11/14/2024,10:55 AM ULTIMATE POLESTAR DETENTION POND AN-F I •• YEAR WSELV MINIMUM AM � '� �C1�ii�i�� • � .�.. -, .���mil• �;1•�'® �1 vit -NIXON um 1 ��1�• 'r t•ui ► �► u , 1Z ■ � \► ter- � �; ■II■ \ � ■.■ mom Wool • HAPPY HEART FARMS DETENTION POND BY JACOBS ENGINEERING GROUP 1 2 4 6 N CONCEPTUAL PROPOSED 18 _ NOT FOR W PROPOSED 18 PROPOSED CURB PROPOSED 18 RCP (TYP.) RCP TYP. INLETS TYP. (TYP.) (TYP.) RCP (TYP.) . L 0 50 100 200 CONSTRUCTION ;t- PROPOSED CURB _ INLETS (TYP.) PROPOSED 72 PROPOSED ,f a--- JUNCTION — - PROPOSED GRAPHIC SCALE FEET PROPOSED _ PRa ED- 30 RCP Q - - - M- - - - -nn -- - - - - - MAp E - VAULT_ _TYP.) JUNCTION - JUNCTION -._x. -. - _- - - - - 41 +00 - _-a _ ( - - -w- - } -- -�-- - w-VAULT TYP. - w- - ( ) cd - r \ � � ORCHARD PLACE- ( ) -_ VAULT TYP. �- W o - O�ROSED OUTLET m _ - F 40+00 3 +00 38+00 37+00 36+0 35+00 34+00 ESIm 33+00 32+00 31 +00 30+00 29+00 28+00 27+00 0 0 ro ! STRUCTURE PROPOSED , /� PROPOSED 60" Q o PROPOSED PROPOSED o Q 5l02 p 36 RCP - o -.MANHOLE PROPO ED 60 I Q o SCE ---MANHOLE 48 RCP f MAN LSE 66 RCP 0 � 4 _. - TYP. PROPOSED u m o 9 . VIEWS + 00 _ (TYP.) 48+00 47+00 46+0 �p S°9� EXISTING 100-YR >_ OND 3 _ FLOODPLAIN wm v7 PROPOSED OUTLET 45 44+00 + PLUM ROCKY ROAD -SPILLWAY STRUCTURE 1 s CHANNEL PLAN AND o oo -- CUT-OFF 0 52+ J ( , -� - PROFILE, SEE EXISTINGPLUM u' Q =0 PROPOSED POND WALL54+� I DWG PC C 003 CHANNEL z v cno GRADING FOR 9.8 AC-FT \ HAP -HEART �, � 00 53+00 100-YEAR VOLUME o PROPOSED 60' � FARMS ND = - _ �' � c� -Q 54+ I MANHOLE (TYP.) I _T-' - �.�. Q �N s�os EMERGENCY � 5;Elf z �� SPILLWAY �l � PROPOSED EXISTING Q EMERGENCY 'S <Q /l SPILLWAY Q CURB INLETS CHANNEL, f- m J �' - � ` z ow 1 1 (TYP.) w � w o \ S1 A o 24" RCP w 1 �. m w� j V D' I 11 I W� � � - PV&L CANAL EXISTING - �� - ,N _ j`� tin - r ' �_ - j l 1 I w v �z . Q f o- m FLOODPLAIN � , Q _ i - _ } y' O IL LLJ ( 1 l PROPOSED POND GRADING. - I ;_�J ,� m , - - 1 - �. 1 - �✓Li w FOR 8.3 AC-FT 100-YEAJ3 -0 FOR VOLUME1\ �" - - NOTES m <W a= o _ B 1. VERTICAL DATUM: NORTH AMERICAN VERTICAL = zo 5125 DATUM OF 1988 (NAVD88) 5125 Y �z � =a o o z o� m m J Y cf) m Lw Q o Of cn U) Q O r" Q � o a- W_ � � D' � � � � � � 1= z c'z z- 5120 — cv C6 5120 o z - > EMER ENCY SPILLWAY Y 00 II C6 00 z cn v,o o ELEV. 5114.5 �- o 0 0� I o o� w �LLJ o LO LO L �n ^. w w EXST GROUND Q _j (D O II II o� ccnn AT CENT RLINE = I Q co II II I Q - - II L oz 5115 L> r- oz z o Lu 000oz o (D � 5115 cW = Qcn PROPOS D OUTLET - - - �o L i L > > > �oz c `n > > °0 Q L cn STRUCTURE AT ---- _ o� z z z bF= z z o N Q m Q z SC NIC VIEWS =)u � ,n II o J T` POND �za �oo N0o �� a � QO Q0 I Q � 00 II � zo o o Qo 5110 cnDcnm -t � � cn� cnm � � w> o � z � 5110 Q � � u zo mz + � _ o �' Q Q ~ V) J J �O oo > > `}U LLJ O w EMERGENCY SPILLWAY o� N z z o}, O z �o EL V. 5105.3 -- �zQ � VL _ o OV) O O OM 5105 cn cn m CO 5105 �'�" Q L o -i PROPOSED OUTLET _ z 5 w v STRUCTURE- AT < _ U' HAPPY HEART z C -0.35 1 % I' FARMS OND PROPOS D m womenNon 0 5100 5100 0 36 RCP, � _ ---__- 0 36" RC , -0.35� 40 .0 LF _ - ,� _ _ w STA. 0+52.72 _ 164.6 LF" FES -0.52 0 - cn INVERT ELEV 5102.00 STA. 4+88.12 - ELEV. 5100.01 5095 w N 0" RCP, 5095 z J N � I PROPOSED 30" RCP, 15.4 LF 1. 5 U) 0 "� -W 117.6 LF Z co + m GRADE - Q o z `n o0QNt Uwm � � IIU Q 5090 � � J Z o a 12m STA. 42+24.43 w w oo Ln � � w d- rn 48" RCP, -0.55� Q —LL O II II � �� I VERT ELEV. 5098.00 0') 0-) o 0 0 I o o m o 317.0 LF m o z -t Lin = o o w o� = + o L i ,, - � J � � z ± nm � � z00LOm 66 RCP, � Q O I rn � Q � � rn Q � � � Q � > O O III o o � III 294.4 LF w 5085 z z Lin Lin N Q �� Lin rn N Q �� .20� 508.E z 060 II II � cnm� II II r- c~i) o'� 66" RCP, W Z � z cn - 389. LF 66" RCP, � U Q o > o > 313.8 LF J Z � J 5080 > z > z z z - 5080 � 0 Q 0 0 U Z o `� 00 D 5075 5075 II 1 "=100' 5070 5070 VERIFY SCALE BAR ORIG ORIGINAL DRAWING.N 0 1" DATE JANUARY 2022 5065 5065 PROJ D3345400 55+00 54+ 00 53+ 00 52+ 00 51 + 00 50+ 00 49+ 00 48+ 00 47+ 00 46+ 00 45+ 00 44+ 00 43+ 00 42+ 00 41 + 00 40+ 00 39+00 38+ 00 37+00 36+ 00 35+ 00 34+ 00 33+ 00 32+ 00 31 + 00 30+00 29+ 00 28+ 00 27+ 00 DWG PC-C-001 SHEET 1 of 4 FILENAME: PCP&P.dwg STAGE-STORAGEDETENTION BASIN MHFD-Detention,Version 4.06(July 2022) Project:Polestar-Ultimate Detention Pond(PLEASE NOTE:THE ABU ON THS MNFD SHEET WAS MULTIPLIED BY 1.2 TO ACCOUNT FOR SEDIMENTATION FOR WQCV) Basin ID: J F10E5 onmce De mIncrement= 1.00 R Optional ptiore POOL Example Zone Configuration(Retention Pond) Stage-Storage Stage Override Length Width Area Override Area Volume Volume Description ft stage ft ft ft ft2 Area ft� acre R' ac-R Watershed Information Top of MICMPool - 0.00 - - - 32 0.001 Selected BMP Type= EDB 5099 - 0.99 - - - 12,276 0.282 6,092 0.140 Watershed Area= 21.50 acres 5100 - 1.99 - - - 42,526 0.976 33,493 0.769 Watershed Length= 1,149 R 5101 - 2.99 - - - 62,048 1.424 85,780 1.969 Watershed Length to.Centroid= 689 It 5102 - 3.99 - - - 69,405 1.593 151,506 3.478 Watershed Slope= 0.011 Rift 5103 - 4.99 - - - 75,067 1.723 223,742 5.136 Watershed 0nperviom ess= 41.ODti percent 5104 - 5.99 - - - 80,847 1.856 301,699 6.926 Percentage Hydrologic Soil Group A= 0.0% percent 5105 - 6.99 - - - 86,761 1992. 385,503 8.850 Percentage Hydrologic$oil Group B= 34.0% percent 5106 - 7.99 - - -- 93,012 2.135 475,390 10.913 Percentage Hydrologic$oil Groups C,/D= 66.0% percent 5307 - 8.99 - - - 99,265 2.279 571,528 13.120 Target WQCV Drain Tim= 40.0 hours Sias - 9.99 - - - 105,638 2.425 673,979 15.472 Location for 1-hr Rainfall Depths=User Input 5109 -- 10.99 - - -- 112,095 2.573 782,845 17.972 After providing required inputs above including 1-hour rainfall 5110 - 11.99 - - - 118,779 2.727 898,282 20.622 depths,dick'Run CUHP'to generate runoff hydrographe Using - - - - the embedded Colorado Urban Hydrograph Procedure. Optional User Overrides - - - - Water Quality Capture Volume(WQCV)= 0.327 -feetacre-feat -- - - - Excess Urban Runoff Volume(EURV)= 0.857 acre-feet acre-feet -- - - -- 2-yr Runoff Volume(P1=0.82 In.)= 0.521 acre-feet 0.82 inches - - - - 5-yr Ruroff Volume(PI=1.09 in.)= 0.792acre-feet inches - - - - 10-yr Runoff Volume(P1=1.4In.)= 1.246 acre-feet 1.40 inches -- -- - -- 25-yr Ruroff Volume(Pi.=1.69 in.)= 1.863acre-feet inches - - - - 5&yr Runoff Volume(PI=1.99 in.)= 2.388acre-feet inches - - - - 10D-yr Ruroff Volume(P1=2.86 in.)= 4.070 acre-feet 186 inches - - - - 500-yr Ruroff Volume(P1=3.14 in.)= 4.594 wnfeet inches - - - - Approximate 2-yr Detention Volume= 0.487 acre-feet - - - - Approximate 5-yr Detention Volume= 0.770 cre-feet - - - - Approximatel0-yr Detention Volume= 1.029acre-feet - - - - Apprulmate25-yr Detention Volume= 1.199 acre-feet - - - - Approximate 5D-yr Detention Volume= 1.309acre-feet - - - - ApproximateIMyrDetentionVolume= 1.951acre-feet - - - - Set Zone 1 as WQCV - - - - Define Zones and Basin Geometry - - - - Zone I Volume(WQCV)= 0.33 acre-feet ser - - - - Zone 2 Volume(U Defined-Zone 1)= 0.00 cre-feet - - - - Zone 3 Volume(10D-year-Zones 1&2)= 1.62acre-feet - - - - TotalDetentionBasinVolume= 1.95 acre-feet - - - - Initial Surcharge Volume(ISV)= user R' - - - - Initial Surcharge Depth(ISD)= ft - - - - Total Available Detemion Depth(1-6�i)= User R - - - - Depth of Trickle Channel(Hrc)= User R - - - - Slope of Trickle Clwnrol(STIC= user ft/ft - - - - Slopes of Main Basin SIdeS(Sic)= user H:V - - - - Basin Length-to-Width Ratio(RU )= user - - - - Initial Surcharge Area(Asv)= user R' - - - - Surcharge Volume Length(Lay)= ft - - - - Surcharge Volume Width(Wsv)= user R _ Depth or Basin Floor(HFMR)= User ft - - - - Length of Basin Floor(L,_,)= user ft -- -- - -- Width of Basin Floor(WFMR)= user it - - -Area of Basin Floor(A-R)= user ft' - - - - Volume of Basin Flonr(y-R)= user ft' -- -- - -- Depth of Main Basin(Hmnw)= user ft - - - - Length of Main Basin Lmst, user R - - - - Width of Main Basin(Wmm = user R - - - - Area of Main Basin(Amnm)= user ft' - - - - Volume of Main Basin(VM,n = user ft' - - - - Calculated Total Basin Volume(V[opi)= unit acre-feet - - - - MHF6petention_0,05-Ultimate Pond.Ism,Basin 11/14/2024,10:00 AM STAGE-STORAGEDETENTION BASIN MHFD-Detention,Version 4.06(July 2022) 20 I.S. 15 89100 $$$3,m 59000 �4 5 29100 0 0 0.00 3.00 fi-00 9.00 12.m 5[age(R) —Leegth(ft) —Width(ft) —A-(S.k) 2.7. 20.640 2055 15.480 C yK 1.320 30.32o v d ; 0.fi85 Sim 0— a.am 0.00 3:W 6.00 9.00 12.W surge(a.) —Area�ages� —Volume lac-k� MHF6pet¢a.0 O9 5-Uffi-e Pold.Ism,Bodo 11t14t2024,10:W AM DETENTIONBASIN OUTLET MHFD-Detention,Version 4.06(July 2022) Project:Polestar-Ultimate Detention Pond(PLEASE NOTE:THE AREA ON THS MHFD SHEET WAS MULTIPLIED BY 1.2 TO ACCOUNT FOR SEDIMENTATION FOR WQC% Basin ID: ZONzo Estimated Estimated t m .. I-+ter-zoNEi Stage(ft) Volume(ac-ft) Outlet Type V01 ��pXTWO. Zone 1(WQCV) 1.43 0.327 Orifice Plate Zone 2(User) 1.43 0.000 Orifice Plate ZONEAND] °RIFlCE aEaraNEx.-% D E Zone 3(100-year) 2.98 1.624 Weir&Pipe(Restrict) Example ZoneConfiguration(Retention Pond) Total(all zones) 1,951 User Inout:Orifice at Underdrain Outlet(tvoically used to drain WOCV in a Filtration BMP) Calculated Parameters for Underdrain Underdrain Orifice Invert Depth= ft(distance below the filtration media surface) Underdrain Orifice Area= ft? Underdrain Orifice Diameter= inches Underdrain Orifice Centroid= feet User Inout: Orifice Plate with one or more orifices or Elliptical Slot Weir(tvoically used to drain WOCV and/or EURV in a sedimentation BMP) Calculated Parameters for Plate Centroid of Lowest Orifice= 0.00 ft(relative to basin bottom at Stage=0 ft) WQ Orifice Area per Row=TN/ ft? Depth at top of Zone using Orifice Plate= 1.43 ft(relative to basin bottom at Stage=0 ft) Elliptical Half-Width= feet Orifice Plate:Orifice Vertical Spacing= 5.70 inches Elliptical Slot Centroid= feet Orifice Plate:Orifice Area per Row= 1.89 sq.inches(diameter=1-9/16 inches) Elliptical Slot Area= fLz User Input: Stage and Total Area of Each Orifice Row(numbered from lowest to highest) Row 1(required) Row 2(optional) Row 3(optional) ow 4(option Row 5(optional) Row 6(optional) Row 7(optional) Row 8(optional) Stage of Orifice Centroid(ft) 0.00 0.48 0.95 Orifice Area(sq.inches) 1.89 1.89 1.89 Row 9(optional) Row 10(optional) Row 11(optional) 12(option ow 13(optionali Row 14(optional) Row 15(optional) Row 16(optional) Stage of Orifice Centroid(ft) Orifice Area(sq.inches) User Input: Vertical Orifice(Circular or Rectangular) Calculated Parameters for Vertical Orifice Not Selected Not Selected Not Selected Not Selected Invert of Vertical Orifice= N/A N/A ft(relative to basin bottom at Stage=0 ft) Vertical Orifice Area= N/A N/A ft, Depth at top of Zone using Vertical Orifice= N/A N/A ft(relative to basin bottom at Stage=0 foertical Orifice Centroid= N/A N/A feet Vertical Orifice Diameter= N/A N/A inches User Input: Overflow Weir(Drovbox with Flat or Sloped Grate and Outlet Pipe OR Rectangular/Trapezoidal Weir and No Outlet Pioe) Calculated Parameters for Overflow Weir Zone 3 Weir Not Selected Zone 3 Weir Not Selected Overflow Weir Front Edge Height,Ho= 1.43 N/A ft(relative to basin bottom at Stage#IBigot of Grate Upper Edge,Ht= 4.43 N/A feet Overflow Weir Front Edge Length= 5.00 N/A feet Overflow Weir Slope Length= 12.37 N/A feet Overflow Weir Grate Slope= 4.00 N/A H:V Grate Open Area/100-yr Orifice Area= 15.56 N/A Horiz.Length of Weir Sides= 12.00 N/A feet Overflow Grate Open Area w/o Debris= 43.05 N/A ftz Overflow Grate Type= Type C Grate N/A Overflow Grate Open Area w/Debris= 43.05 N/A ftz Debris Clogging%= 0% N/A % User Input:Outlet Pioe w/Flow Restriction Plate(Circular Orifice.Restrictor Plate.or Rectangular Orifice) Calculated Parameters for Outlet Pine w/Flow Restriction Plate Zone 3 Restrictor Not Selected Zone 3 Restrictoi Not Selected Depth to Invert of Outlet Pipe= 0.00 N/A ft(distance below basin bottom at Stage=0 ft) Outlet Orifice Area= 2.77 N/A ftz Outlet Pipe Diameter= 30.00 N/A inches Outlet Orifice Centroid= 0.79 N/A feet Restrictor Plate Height Above Pipe Invert= 16.50 inches Half-Central Angle of Restrictor Plate on Pipe= 1.67 N/A radians User Input:Emergency Spillway(Rectangular or Trapezoidal) Calculated Parameters for Spillway Spillway Invert Stage 8.78 ft(relative to basin bottom at Stage=0 ft) Spillway Design Flow Depth= 0.62 feet Spillway Crest Length= 36.80 feet Stage at Top of Freeboard= 10��acre-ft 50 feet Spillway End Slopes= 2.50 H:V Basin Area at Top of Freeboard= acres Freeboard above Max Water Surface= 1.10 feet Basin Volume at Top of Freeboard= Routed Hydro rah Results The user can override the default CUHP hydrographs and runoff volumes by entering new values in the Inflow Hydrographs table(Columns W through AF). Design Storm Return Period= W, CV V 2 Year 5_Y_ear 10 Year ­� 50 r r 5 1C f One-Hour Rainfall Depth(in)= N/A N/A 0.82 1.09 1.40 1.69 1.99 2.86 3.14 CUHP Runoff Volume(acre-ft)= 0.327 0.857 0.521 0.792 1.246 1.863 2.388 4.070 4.594 Inflow Hydrograph Volume(acre-ft)= N/A N/A 0.521 0.792 1.246 1.863 2.388 4.070 4.594 CUHP Predevelopment Peak Q(cfs)= N/A N/A 0.2 1.2 5.4 12.8 17.9 34.2 39.2 OPTIONAL Override Predevelopment Peak Q(cfs)= N/A N/A Predevelopment Unit Peak Flow,q(cfs/acre)= N/A N/A 0.01 0.05 0.25 0.60 0.83 1.59 1.82 Peak Inflow Q(cfs)= N/A N/A 6.6 10.3 17.1 26.7 34.1 56.9 64.0 Peak Outflow Q(cfs)= 0.2 6.2 0.9 2.3 5.3 10.6 15.1 20.6 21.6 Ratio Peak Outflow to Predevelopment Q= N/A N/A N/A 2.0 1.0 0.8 0.8 0.6 0.6 Structure Controlling Flow= Overflow Weir 1 Overflow Weir 1 Overflow Weir 1 verflow Weir Dverflow Weir I Overflow Weir 1 Overflow Weir 1 Outlet Plate 1 Outlet Plate 1 Max Velocity through Grate 1(fps)= N/A 0.15 0.02 0.1 0.1 0.2 0.3 0.5 0.5 Max Velocity through Grate 2(fps)= N/A N/A N/A N/A N/A N/A N/A N/A N/A Time to Drain 97%of Inflow Volume(hours)= 37 38 41 40 37 34 31 25 24 Time to Drain 99%of Inflow Volume(hours)= 40 44 45 45 44 42 41 37 36 Maximum Pending Depth(ft)=F071,43 2.08 1.60 1.78 2.00 2.28 2.46 3.17 3.42 Area at Maximum Pending Depth(acres)= .59 1.02 0.70 0.82 0.98 1.101.18 1.45 1.50 Maximum Volume Stored(acre-ft)= 331 0.859 0.434 0.571 1 0.779 1 1.060 1.265 2.228 1 2.582 MHFD-Detention_v4-06-Ultimate Pond.xlsm,Outlet Structure 11/14/2024,9:59 AM DETENTIONOUTLET MHFD-Detention.Version 4.06(July 2022) 70 �500YR IN .....5OOYR OUT �100YR IN 60 —100YR OUT �SOYR IN SOYR OUT s0 25YR IN 25YR OUT 10YR IN 10YR OUT 40 �SYR IN •••••SYR OUT 30 �2YR IN 2YR OUT EURV IN •EURVOUT WQCV IN 20 ....WgOv our 10 �— 0 0.1 1 TIME[hr] 4 —500YR —100YR 3.5 —50YR 25YR 10YR 3 —SYR —2YR EURV 2.$ —w-1- i 0000 O 2 O 2 O 2 0000 O a 1.5 1 0.5 0- Tfl 0.1 1 10 DRAIN TIME.[hr] 700,000 O User Area[W2] —Interpolated Area[W2] ••♦• Summary Area[ftA2] 600,000 _Volume[ftA3] ••4••Summary Volume[W3] 500,000 —Outflow[Cfs] ••i••Summary Outflow[cfs] 400,000 f O 9 r 300,000 x a 200,000 100,000 0 0.00 2.00 4.00 6.00 5.00 50.00 12.00 PONDING DEPTH[ft] S-A-V-D Chart Axis Override X-axis Left Y-Axis Right Y-Axis minimum bound maximum bound MHFD-Detention_v4-06-Ultimate Pond.xlsm,Outlet Structure 11/14/2024,9:59 AM DETENTIONBASIN OUTLET Outflow Hydrograph Workbook filename: Inflow Hvdro0ranhs The user can override the calculated inflow hydrographs from this workbook with inflow hydrographs developed in a separate program. SOURCE CUHP CUHP CUHP CUHP CUHP CUHP CUHP CUHP CUHP erval TIME WQCV[cfs] EURV[cfs] 2 Year[cfs] 5 Year[cfs] 10 Year[cfs] 25 Year[cfs] 50 Year[cfs] 100 Year[cfs] 500 Year[cfs] in 0:00:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0:05:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0:10:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.20 0.36 0:15:00 0.00 0.00 0.24 0.78 1.31 0.91 1.33 2.05 2.38 0:20:00 0.00 0.00 2.01 3.04 4.16 2.76 3.50 5.38 6.31 0:25:00 0.00 0.00 4.92 7.77 12.47 6.82 8.89 16.78 20.12 0:30:00 0.00 0.00 6.65 10.33 17.09 20.67 27.33 45.21 51.38 0:35:00 0.00 0.00 6.58 10.17 16.60 26.22 33.86 56.88 64.02 0:40:00 0.00 0.00 6.14 9.29 15.11 26.72 34.12 56.70 63.68 0:45:00 0.00 0.00 5.46 8.33 13.57 24.83 31.66 53.75 60.30 0:50:00 0.00 0.00 4.88 7.58 12.07 22.96 29.23 49.58 55.64 0:55:00 0.00 0.00 4.41 6.80 10.76 20.36 26.02 45.10 50.62 1:00:00 0.00 0.00 3.95 6.05 9.55 17.95 23.03 41.07 46.08 1:05:00 0.00 0.00 3.56 5.40 8.46 15.83 20.37 37.33 41.89 1:10:00 0.00 0.00 3.16 4.96 7.77 13.43 17.32 31.66 35.65 1:15:00 0.00 0.00 2.87 4.54 7.30 11.74 15.19 27.31 30.83 10 1:20:00 0.00 0.00 2.63 4.12 6.66 10.20 13.19 23.14 26.12 1:25:00 0.00 0.00 2.41 3.73 5.85 8.87 11.44 19.47 21.97 1:30:00 0.00 0.00 2.20 3.36 5.09 7.56 9.70 16.30 18.38 1:35:00 0.00 0.00 1.98 3.00 4.37 6.36 8.10 13.40 15.10 1:40:00 0.00 0.00 1.78 2.56 3.71 5.24 6.62 10.74 12.09 1:45:00 0.00 0.00 1.59 2.17 3.14 4.21 5.27 8.37 9.43 1:50:00 0.00 0.00 1.47 1.91 2,79 3.32 4.14 6.52 7.38 1:55:00 0.00 0.00 1.30 1.75 2.56 2.81 3.49 5.40 6.13 2:00:00 1 0.00 0.00 1 1.16 1.61 2,33 1 2.50 3.09 4.67 1 5.31 2:05:00 0.00 0.00 0.94 1.31 1.89 1.97 2.42 3.59 4.09 2:10:00 0.00 0.00 0.75 1.04 1.50 1.51 1.86 2.69 3.07 2:15:00 0.00 0.00 0.60 0.82 1.18 1..17 1.44 2.00 2.29 2:20:00 0.00 0.00 0.48 0.65 0.92 0.90 1.10 1.47 1.68 2:25:00 0.00 0.00 0.38 0.51 0.71 0.69 0.83 1.09 1.25 2:30:00 0.00 0.00 0.29 0.39 0.54 0.53 0.63 0.83 0.94 2:35:00 0.00 0.00 0.23 0.30 0.41 0.40 0.47 0.62 0.71 2:40:00 0.00 0.00 0.18 0.23 0.31 0.30 0.36 0.48 0.54 2:45:00 0.00 0.00 0.14 0.17 0.24 0.23 0.27 0.37 0.42 2:50:00 0.00 0.00 0.10 0.13 0.18 0.17 0.21 0.28 0.31 2:55:00 0.00 0.00 0.07 0.09 0.12 0.12 0.15 0.19 0.22 3:00:00 0.00 0.00 0.05 0.06 0,08 0.08 0.10 0.13 0.15 3:05:00 0.00 0.00 0.03 0.04 0.05 0.05 0.06 0.08 0.08 3:10:00 0.00 0.00 0.01 0.02 0.02 0.02 0.03 0.04 0.04 3:15:00 0.00 0.00 0.01 0.01 0.01 0.01 0.01 0.01 0.01 100 3:20:00 0.00 0.00 0.00 0.00 0,00 0.00 0.00 0.00 0.00 3:25:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3:30:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3:35:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 300 3:40:00 0.00 0.00 0.00 0.00 0,00 0.00 0.00 0.00 0.00 3:45:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3:50:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 3:55:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 250 4:00:00 0.00 0.00 0.00 0.00 0,00 0.00 0.00 0.00 0.00 4:05:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4:10:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 200 4:15:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4:20:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4:25:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0 4:30:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1501-' 4:35:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 D 4:40:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0 4:45:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 4:50:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 100 4:55:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5:00:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5:05:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5:10:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 50 5:15:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5:20:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5:25:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5:30:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0 5:35:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 I 5:40:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5:45:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5:50:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5:55:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 6:00:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 MHFD-Detention_v4-06-Ultimate Pond.xlsm,Outlet Structure 11/14/2024,9:59 AM DETENTIONBASIN OUTLET MHFD-Detention,Verslon 4.06(July 2022) Summary Stage-Area-Volume-Discharge Relationships The user can create a summary S-A-V-D by entering the desired stage increments and the remainder of the table will populate automatically. The user should graphically compare the summary S-A-V-D table to the full S-A-V-D table in the chart to confirm it captures all key transition points. Sra a g g Stage Area Area volume volume OTotal AN -Shore e Description [ft] [R'] [acres] [R'] lac-ft] [crs] For best results,include the stages of all grade slope changes(e.g.ISV and Floor) from the S-A-V table on Sheet'Basin'. Also include the inverts of all outlets(e.g.vertical orifice, overflow grate,and spillway, where applicable). MHFD-Detention_v4-06-Ultimate Pond.xlsm,Outlet Structure 11/14/2024,9:59 AM Stage Discharge Project Name: Polestar Subdivision:Polestar Project No.:39797.01 Location:Fort Collins Calculated By: ARJ Checked By: Date: 11/13/24 INTERIM-OUTLET ULTIMATE-OUTLET WQ orifice plate,w/Restrictor Plate 42"Pipe and Overflow Structure WQ orifice plate,30"Pipe w/Restrictor plate and Overflow Structure Head(ft) Discharge(cfs) Head(ft) Discharge(cfs) 0 0.00 D 0.00 0.5 0.05 0.5 0.05 1 0.12 1 0.12 1.36 0.16 1.43 0.18 1.5 0.73 1.5 0.35 2 7.29 2 5.26 2.5 21.17 2.5 16.23 3 31.67 3 19.82 3.5 35.21 3.5 21.94 4 38.42 4 23.88 4.5 41.39 4.5 25.67 5 44.15 5 27.34 5.5 46.76 5.5 28.92 6 14922 6 30.41 5 576.5 31.84 7 82 7 33.26 7.15 48 7.5 34.51 SEE WQCV STAGE IN RED 8 35.77 8.5 36.99 9 38.17 9.5 39.32 10 40.43 SEE WQCV STAGE IN RED NOTE:In the Jacobs SWM M model the outfall was modeledasa 30"unrestricted pipe. Appendix J-3 SWMM Maps Zt Legend _1 z Lu 0 T Junction L7 4� LLJ # _-N17 Outfall Z Storage Z Conveyance Element 'Tow 7 C7 - - - - Non-Routing Element 7i_ 0-4 - , ... - I 1L A'wl Wt, � " 4",�qf . I�� --- ,, , - - I I 1 1 1 1 11 k I � I t - - - .I . I c AA T 4? A41 Outlet L c CIO r 4 N, A 10, 91 C3 Subbasin A A "7* Ei 7= 4 > , I , - a 0 7 n4 4- 4k C-ir 4 tali, Vigil "IMP' i:A, sai 4'* �h*. *f --Z A.# uj it 4 .4 AN _,7, ^'It uj 71. 7 z ;1V In, I d Uj AIM 428 Spil _AL F28 410 j 0 1 411.- 11%, '04 A,� jik,* A 0 .4 71W, r D 4 1 7 4M 1-1 Z� - ,��I 4 1- . _ . k 41 ,--Wjlr 7 4 F2 I A oi 'i '4 oil C 'A _4 VO' -A �xi' 4 0 4 E7 7 13cl� 44mft A" pop 859 4 _1304 311 WNW.4l"",r PI F 02 J3 10 J105 pip, F7p i 7pe 103 �ipe 1 15-pip vetflow p [MI ovemow Mulberry Street ....... iL 05 % Mulberry Street J945 J709 3 J148 311 outfall q Al, �7 7. 4k x 7- V, 8 utfall Y41 4 308 8 e - -4 15 xe: J J108 108 'PIn 8 J8 AL C) 1143 __7 IT 0 79 J711 > LO It 11� ;j..i J5 21 J21 i 442 Spill A 713[JUtt k1l 1,3-11�21 M2 712 Ou fall 713 0 J712 J713 J121 13 71- A 4w J17 M7 LU 310 J117 [go ilo-pipe k;m-1 If* J0 114 uvtfutow e Er- 4�1 J113 0-_ N F_ 313 15 L) ac. 5 il 0 f"�A f; F,g7p—i p--el 316 93 J714 15_pipe F 1-61 1-D J513 71 utfall -pipe 18 overfil) LL q, J120 J10 423 _Af J115 655 854 IF 856 J116 4 J118 e .Mi I LL 12 Cl) 5 M JI/IJL #MWM&..Jm - 22 322 7 r <1 201 4 18 3 A31 319 C C 715 Outfall 'k, GC 224 _7 R 950 si* a- 8 0 Inlet J42 A, -950 kylin Ailli�v %7- GIC 117 0 3 2 uttall r 7� InIbt2 19 533a A2 8�,2 Ail J533 IsOyline J418 1141) e 118 533 A�25 543 N PIN "14 �77�f acL 14 J523 83 7 3.3 543 J543 US 299 2 324 9 523 ac 318 A24 p PP_3 rn_� 12.8 ac. J583 9 r, A22 PP 1 Spill 22 A21 A2 Elizabeth Street 3 8701 529 PIP 7 5 J519 529out 7 J589 =& 4 519out �,ja 1.4 6 1 7 9 1.6 J579 J569 (N N 118 1 7 299 Outfall MIA&I 869 J549 17k ij: 579 A 549 outfa Aw AL CID 366 Skyli -367 X_-) JSS9 445 Spill r -71, ALA 11 1 6i ir Ai" e ir��t e /'50'9 J719 719 -pipe _4; 119 Stora 719 0 f 59. 70 802 A17 CL 98 J94 1:0 0 200 400 800 a 378 Outfall is 115�� Q 368 JM Ili L C8 378 Feet 370 Ada 395 -2 7-, Al a 14 e 1.7 J93 )s F-7 11 871 Avery LowFlow 1,2,_ 588 ac. DRAWN BY- BNA 399 272 110 Avery Outlet 0 DESIGNED BY: MMC 1, 300 861 274 577a 520 Outfall 862 557 J550 4 ------ CHECKED BY- AMH ON40 okuh! I 302 A14 4- PROJECT NUMBER: 276 16 570 jy In 'F COFC2012.01 187 V 1!4!kill, e If 4L 560 -3 720 Ou '88-PiPe 4 4.3 h20 A FC20 DATE: 30 303— R e 16-3- 98 741 C) L6-2 4 07/01/2014 J34 0.8 C_ 6-2 4/13 290 ac. 446 Spill 306 % 587 1587 Is 16-1 - 47 Outfall SHEET: 396 L597:�j LO IB-1 390 00 f 87�3 V) z_ LLJ z � � z cn Ld wwotw- w 0- i— QQwwzSo � LEGEND NOTE IN THE SWMM MODEL THERE IS o w w z F- z } mo � m � =-5 XX XX — BASIN NAME BASINS HATCHED IN GREY ARE ADDITIONAL RUNOFF FROM TIME o o — cn 0' o N CONDUIT NOT IMPACTED OR TRIBUTARY SERIES HYDROGRAPHIC 401 — n > a_ w > o Q X.X X.X — BASIN AREA H OUTLET TO THE PROPOSED SITE WHERE OVER FLOW PV&L DITCH 1n o o :z o z o CHANGES SPILLS INTO THE SCENIC VIEWS z = Q- Q- C) CL z w � D FLOW ARROW FOR ELEMENT JUNCTION POND I.E. POND 313. ~ Q Q Q o 0 Q X POND BASIN DELINEATIONS FROM 2014 Z CANAL IMPORTATION BASIN — Ln CD EFFECTIVE BASIN DELINEATION Uj cal 0000 CO ow oLn0M EL:11 � N r� w Q c I I Q c� xz � I I 0- Q m ❑ 00 I I Li w 00 CD LLJ O 0 � LL r , 1L 1 U S I #- CL --- - - - - — - - - - - W. MULBERRYST. � M �I cC rn r 75 Qr Q) I - J17: 198.4 CFS .1 ui ' 1 _ Q 5 _ 17 W _ { .� POND 313: 348.7 CFS 13 2.9 n�,n,U.,-„w,,.... _ 17 Jl l _ _ O D PL El \E-ED - POND 315:1200 CFS° N 310 � 313 c, J10 I eT 110_OVERFLO ' �W J113 15 15_PIPE 6-PIPE ' 1 � - I I ❑ � >>3 ♦ 315 8_PIPE �� �� 856 �J1157 316 �J116 116 �54 J118 -x .- � JI J88 OW , ❑ I I ❑ D 110_OVE RFL 65 ��• 16_OVERFLOW `,, ❑ i� �Z� POND 313: 156.2 CFS 115_OVERFLOW 11 �� NODE 853: 209.3 CFS 15 W uM 0 ,ti � III 23.1 � � z PL ST 3� I w c SCENIC VIEWS p N Q Q �- 0 w w m > m WEST EL/ZABETH ST. Q Q 0 0° o Ld o 0 < Y Q w > LLJ U_ F- z Q w a- W T Q :E U CD z F- 0 Q O W X � J Ld O 300 150 0 300 600 ORIGINAL SCALE: 1" = 300' SHEET 1 OF 4 JOB No. 39797.01 V) z_ LLJ Ld zm � z LAL.Li 0 cn w i - �- QQWwzSm � LEGEND NOTE wN � WZC)f IN THE SWMM MODEL THERE IS m w w w z Wiz } = mp ADDITIONAL RUNOFF FROM TIME Q Q a m cn ~ L Q BASINS HATCHED IN GREY ARE � a 1u m w w o ~ �' rx—x*,� XX — BASIN NAME ❑ CONDUIT NOT IMPACTED OR TRIBUTARY WHERE OVEDR OFLOW PV8cL0DITCH J u o p z p Z o TO THE PROPOSED SITE F- wmmwm � Uj X.X X.X — BASIN AREA SPILLS INTO THE SCENIC VIEWS z = m m 0 m z w El PROPOSED CONDUIT CHANGES POND I.E. POND 313. � � aQaaooa FLOW ARROW FOR ELEMENT H OUTLET BASIN DELINEATIONS FROM 2014 CANAL U N X POND JUNCTION IMPORTATION BASIN ? o N00 Ln 0 PROPOSED POND J � MODIFIED BASIN DELINEATION ❑ o Ln O °� PROPOSED JUNCTION U I I I 0 N r� w Q c I I Q c� xz � I I 0- Q m ❑ 00 I I w w 00 CD LLJ O 0 � L y� C�_� an cc W. MULBERRYST. CL -1 #61 %qw c D C) \ 5C 1 � p U ,+ 10.2 1167E C6 o � l►,� , - 13 � _<p � J17: 95.8 CFS = 2.9 } _ J17 1 ' J11 ORCHARD PL f E 313out:252.2 CFS— — — ❑ 110_PIPE ( M •� 310 �� � ' 31� POND 23: 321.9 CFS, � � � ~ \f � J10 I f 1110_OVERFLOW' 315 8_PIPE 10 - I I ❑❑ a J115l 316 �J116 116 �54 0_OVERFLOW J118 I POND 313 :348.6 CFS / I J88 ❑ I I ❑ D 11 � ��\ _ I 16_OVERFLOW t ❑ , 115_OVERFLOW 15: 311.6 CFS EP I III 40 23.1 -� 21 .5 — 15E _ W PLUM�ST cn 14 > cn *. f Z III �e �0 9 w r W c SCENIC VIEWS77 � z ID o-iiiiiu r I II z Q Q n (� - O — _ - - - m WEST ELIZABETH ST. — — Q -i o m o Ld _ > Ld w _ p U U (� Cf) F- z Q Ld :2 w > Ld T 0 Ld Z LL- Q F- W 75 O W Ld < 00 U Ld rr � 0 300 150 0 300 600 U ORIGINAL SCALE: 1" = 300' SHEET 2 OF 4 JOB No. 39797.01 V) z_ LLJ LLI Ld zm � z LAL.Li 0 cn w m �— QQWwzSm � LEGEND NOTE wN � WZC)f IN THE SWMM MODEL THERE IS m w w w z Wiz } = mp ADDITIONAL RUNOFF FROM TIME Q Q a m cn ~ L Q BASINS HATCHED IN GREY ARE � a 1u m w w o ~ �' rx_x*,� XX — BASIN NAME c❑ CONDUIT NOT IMPACTED OR TRIBUTARY WHERE OVEDR OFLOW PV8cL0DITCH J Lu o p z p Z zo TO THE PROPOSED SITE F- wmmwm � Uj X.X X.X — BASIN AREA SPILLS INTO THE SCENIC VIEWS z = m m 0 m z w E:1 PROPOSED CONDUIT CHANGES POND I.E. POND 313. aaooa FLOW ARROW FOR ELEMENT H OUTLET BASIN DELINEATIONS FROM 2014 CANAL U N X POND JUNCTION IMPORTATION BASIN ? o N00 Ln 0 PROPOSED POND J � MODIFIED BASIN DELINEATION o Ln O °� PROPOSED JUNCTION U I I I 0 N r� w Q I I Q c� xz � I I 0- Q m o � I I w w 00 CD LLJ O 0 � L 11 >f� + N { f . i O _ — 4' # ) o c � o ALcc c p L �1 ;. - - - - — - - - - - W. MULBERRYST 0 . O • • r_ N �. � C # O `5 5 C o ,. 17W �� _ a - 10.2 J 17E r NODE 23:361.8 CFS 1 4•$ J17: 95.8 CFS I m O INTERIM—OUTLET: 49.6 CFS j \ 313out: 244.8 CFS: 132.9 =AA J J14:174 CFS� 1� � � J11 ORCHARD PL El _T -t- _r _r K) "CF ALi J37 1110_OVERFLOW� I � I — 23 -M-15 5_PIPE 6_PIPE _ f r � � � • ,J14 _ 315 1 � � I ❑ I \� � � �/� I 1115� 316 J116 116 �54 MMOMWY J118 y 65 I I I ❑ D `� I SPIT I WAY_OUTFAL�_ 16_OVERFLOW 11o_oVERFLOW 115_OVERFLOW I V@�— y 313: 348.6 CFS I +� !SPILLWAY 124.2 CFS M-15:174 CFS 0 W PLUM ST I U) *• \ 91 W I ��� 21 .5 If l z • , C SCEV/C VIEWS El. I Q +t► r� �� \ Id 0 N O Q \ � � r z 0o Q a w m - Lu m m WEST EL/ZABETH ST. - J J 0° i � Q Q � LIJ zLd Q 0 < Y r � � Q U _ W p � U C U (� Q F- z � Q w W CD � CD 11110, Z F- D Q 0 O W _ U Ld O < J a_ O O 300 150 0 300 600 ORIGINAL SCALE: 1" = 300' SHEET 3 OF 4 JOB No. 39797.01 V) z_ LLJ Ld zm � z LAL.Li 0 cn w o_ r QQWbi Sof LEGEND NOTE wN � WZC)f IN THE SWMM MODEL THERE IS cr Wiz } = mp BASINS HATCHED ADDITIONAL RUNOFF FROM TIME U o - u w Of o N ("X-X� XX BASIN NAME El CONDUIT SERIES HYDROGRAPHIC 401 — ccn p > o_ w > O Q YELLOW WERE NOT 0 0 U3 0 z O X.X X.X — BASIN AREA MODIFIED WHERE OVER FLOW PV&L DITCH J n o- of z c- >- 0 _ PROPOSED CONDUIT SPILLS INTO THE SCENIC VIEWS z z a- a- (D CL z w POND I.E. POND 313. � � QQQQO0Q D FLOW ARROW FOR ELEMENT H OUTLET BASIN DELINEATIONS FROM 2014 CANAL X POND J JUNCTION IMPORTATION BASIN z O PROPOSED POND PROPOSED JUNCTION MODIFIED BASIN DELINEATION o z Ln O m 0 M wLd U p N � � I I ww Q I I Q c� xz � I I 0- Q m o 00 I I Li w (j CL 0UCD CD LLJ O 0 � L I I 1YY9 1 y d I C!) '� , } • VL r O • * [V� _ � O �1 - - - - — - - - - W. MULBERRYST. 0 U •TL • ' I , M c CD rn I 75 c -c JACOBS OUTFLOW 47.01 CFS �Q) JR ENGINEERING OUTFLOW: 38.57 CFS .. ...y� • � 17W o 17E Q 2 �' - I p • 313out: 55.15 CFS 10. 14.8 313: 348.7 CFS Q m 171 + 4, J L_ Q J14 J17 72 /C5_1 } I — 313ou t — - J6 J15 ORCHARD E 110_PIPE PL ' 23: 221.2 CFS 310 313 , T \ Am 1110_OVERFLOW' I I I J115 a — 23 C7 - I 315 :513_SLWAY J11 1 0 PIL - I J115 w-w ❑ .- y - �— ' JACOBS INFLOW: CFS 65 I I ❑ D �� /� � SPILLWAY_OUTFAI I JR ENGINEERING 0 0 CFS � 15E THERE IS A SUMP W/ jpm • 11 ��0 (� I I I�.' 9 TWO INLETS HERE 1 I 23.1 -< < 21 .5 W PLUM ST • w . 11 W c� z � I � d�� " 313—SPILLWAY. 0 CFS C SCENIC Vlf-WS � iL�I APILLWAY—OUTFALL: 0 CFS ° 0 c\A 0 < oo n- a� ^II z Q Q — w w m m WEST ELIZABETH ST. J J 0° Q Q � � z p Ld U U Q Y Q W _ > W p = p U J U W Z 0 Q Ld w U z cn D Q O D' t � ~ Q J < � O � J � 300 150 0 300 600 ORIGINAL SCALE: 1" = 300' SHEET 4 OF 4 JOB No. 39797.01 Appendix J-4 Offsite Photos and Calculations POND 315 OUTFALL - DUEL 24" RCP EAST OF KIMBALL STEET •r �I Nj ROCKY ROAD - DUEL 24" STORM UTILITY MARKINGS - (ON WEST SIDE) I �I 1 d3 f v POND 316 INFLOW PEAR STREET- (FACING WEST) fF 1 r I UPDATE OF HYDROLOGIC ANALYSIS FOR WEST PLUM STREET BASIN CANAL -rMP0RTAT.z0N BASIN Prepared for City of Fort Collins Stormwater Utility P.O. Box 580 Fort Collins, Colorado 80522 AWE ASSOCIATES formerly Resource Consultants & Engineers P.O. Box 270460 Fort Collins, Colorado 80527 (970) 223-5556, FAX (970) 223-5578 Ayres Project No. 34-0296.00 - _ - - W-PLUM10.RPT - ;' October 1995 4' Revised April 1996 � aA ASSOCIATES 832 :. . ' RESOURCE by date sheet of CONSULTANTS, chkd by date job no INC. subject Cis �t �/ Gam,,-i T.r.i e�Y)rc,T Fort Collins, Colorado 7 6Y �� /v �• F=y Ae-5 ygzz 2 . 3o ew LAC so .2.SL S-CU or. c1r//EY c�-�rjy,>/ _ f�/. /'i /- r„id-rr_-:'• %ri+�;� Fy,,v ,r-/,-r-• 1-74 r Z file�v 7afa T W H W td 114l:, aw 2 y I Z (•35 /,97 /. !07 31 3S S, e,3 < 2oK :t<rn77;FYr 72 CwJ J6 L 55 I y 6O 9S-5Y /, 3 y In 95 I i f RESOURCE by date sheet--- o' CONSULTANTS, chkd. by date job no. INC. subject Fort Collins, Colorado -3!12 R ze!"61' X! /Op :5 3 2, S All I lq7, 7 7 1, 3 & 41 4J- 0 &(I rOW9 kW4-y A-7-mi 4,9... 1c)I VOLUAA& Doc)-7q4 CW—LT&L 0 p 0 Or 4L'&-�49wy- edc� /PV RC;OURCC by date— men-9 CONS TkNT chkd. by— date job no INC. subject - - «: .«e: \ 3\ Fort Collins, Colorado JAI / $\\ ' IT, \ . � \ \ \�� NZ (D -t't Inj CHART 2 10,000 F— 168 I 8,000 EXAMPLE t" 1S6 6,000 0.36 i.gh.e 13.0 bat 6. 121 5,000 0.46"' (3) 144 4,000 Hw 4 Mw S. e• 132 3,000 0 (1etl) 6 s. , ti 120 m 2,000 19 1.1 6.3 e• 131 :.: 4.6 4' toe '0 L tees 3• 4. i j 96 : 1,000 3. 800 3• 84 el 600 �f 2.500j 72 j 2. 2. N I 300 • U N i// = 1.5 I W z L 60 J_ = 200 ��% Q I.s 1.5 54 O // W 100 J W L 48 s 60/ v 60 I.0 LLa2 N SO//i I.0 C 40 Q L0 G j w 36 0 w gG�LE ENTYPECE W W a S3 20 (U Il.ee.a o .6 .e a a 30 f21 Yllau a eeelerw W .e u e 2T 0 (31 Oaiem lns T 7 e 6 7 N To .C4M 111 0131 Pel.el 21 4 n� p u4p 01 IM. •6 eee eva6M �H.; IvwIn •6 , 3 0 e44 0 .telu, er was .6 Ie tu.elnu6. _ 2 ' 15 e 1.0 s 12 HEADWATER DEPTH FOR C. M. PIPE CULVERTS WITH INLET CONTROL W IK.W 0!.V6LIC R0603 AK M43 182 CHART 6 2000 — 1000 goo J srr. t,.— , .6 WOWS o OUTLET CULVERT ILO.R56 PULL 120 600 iw wl.l eSRw w ...RI•M,saWS Rr M .g 500 106 .nwu pbJR• . R. M.M RkR•r• 10 400 96 !00 g4 OP. O yp C �F 200 T2 It y 66 �O ''!•cp ?I'Y UU 2 60 O l<J U S4 /Sn 00 00 F x 3 = 4g O °�� F� a g0 U t 00 = 42 =H4 60 = / a SO o S6 ' ( Vj 40 33 300 6 27 /� 0 10 j4p0 {/ 500 /2 500 10 Ig % 20 g i� 6: 1 S � S 4 12 3 2 HEAD FOR STANDARD C. M. PIPE CULVERTS FLOWING FULL n a 0.024 RURUU 0/ "L1C MAM YR. rou 186 3 ac 2 I .0' do CannoP Exceed Top of Pipe I.O DIA 0 0 10 20 30 40 50 60 70 80 90 100 DISCHARGE (Q) C.F.S 6 8 5 7 I— H w 4 e I w w _ 9 L" u U do Cannot Exceed Top of Pipe a �- 3 5 ,- _ 7 x � t- a. a 0 2 D A. w 0 100 200 300 400 500 600 700 800 900 1000 I= DISCHARGE (Q ) C.F.S. Q' ;Z 14 F- FE U 12 10 8 6 do Cannot Exceed Top of Pipe i 13' 4 DI 0 1000 2000 3000 4000 DISCHARGE (0) C.F.S. Figure 7.4.3- 4 CRITICAL DEPTH CIRCULAR PIPE ( From : U.S. Dept. of Commerce, Bureau of Public Roads, Dec. 1965) 7.4---15 � a r,•. t r a • K.}.. t : fill .• no's � '- �® NOW • lit - r a ®®Ill® �®IN 5 k Trn j: j 5 :1 \ :'r' r 1 d,._ t> a,'..,; a�...�..ai:a a ria s✓..; - t ✓`",-. r •e•� ..r:w M+�tn..pG - s 'EJf •v`ytl CF}�....y1 + .1.i�.S} i{ I!A'.5�t_..cli +' �_ea.e^.fi .rY1. •4..,'•i� �• _ tt r 4 = • V r& Lv - y S + i' LL� s ti 1 zl t ._ ... S i.` J45. it ,. .... .�x.� �. .. ..•, .r .... ' '. RESOURCE by date I v-b B-e 8 sheet of CONSULTANTS, chkd. by date job no. r 4 r r INC. subject a.d Fort Collins, Colorado �p A Lbrtt' T3 Nq cl API a-W0.y — - 4) (too,N) - 9 4o ti I; I (971) (98z) \ -- 400 4o1 397 rd G OCOAfo ----- �06 8 �l N' N , Xa 'S1. '�'r�.cT.,5�'K �✓;yr`t 4pZ,E�' .yu x>< �a - �-r LL cl CO 1 ... _ i 1 ol +' � a,). Y\ Y izi �hSa'S�i'1�EiAa�'�i:`��'�FF'?F ht t. f�:•�`_N"t.n �:.t �^! .s iSs ��.i,r J��- f ey Sir.•'z4 Y��' ��.r•-�irn ne �-- •'... ',` i f MHFD-Culvert, Version 4.00(May2020) Project: Kimball Detention(Pond 315 Culverts) ID: CO-*V.m e I° o 1- ......i.............} M : >keY Design Information(Input): Circular Culvert: Barrel Diameter in Inches D= 24 inches Inlet Edge Type(Choose from pull-down list) Grooved Edge Projecting OR: Box Culvert: Barrel Height(Rise)in Feet H(Rise)=�ft Barrel Width(Span)in Feet W(Span)= ft Inlet Edge Type(Choose from pull-down list) Number of Barrels #Barrels= 2 Inlet Elevation at Culvert Invert Elev IN= 5096.6 ft Outlet Elevation OR Slope So= 0.005 ft/ft Culvert Length L= 440 ft Manning's Roughness n= 0.013 Bend Loss Coefficient Kb= 0 Exit Loss Coefficient K.= 1 Design Information(calculated): Entrance Loss Coefficient K.= 0.20 Friction Loss Coefficient Kf= 5.43 Sum of All Loss Coefficients Ks= 6.63 Minimum Energy Condition Coefficient KEIo = 0.0028 Orifice Inlet Condition Coefficient Cd= 0.67 Calculations of Culvert Capacity out Out): Backwater calculations required to obtain Outlet Control Flowrate when HWo<0.75*Culvert Rise Headwater Tailwater Inlet Inlet Outlet Controlling Flow Surface Surface Control Control Control Culvert Control Elevation Elevation Equation Flowrate Flowrate Flowrate Used ft ft Used cfs) (cfs) (cfs 5096.60 5095.20 No Flow WS<inlet 0.00 0.00 0.00 N/A 5096.85 5095.20 Min.Energy.E n. 0.50 #N/A #N/A #N/A 5097.10 5095.20 Min.Energy.E n. 2.32 #N/A #N/A #N/A 5097.35 5095.20 Min.Energy.E n. 5.06 #N/A #N/A #N/A 5097.60 5095.20 Min.Energy.E n. 8.68 #N/A #N/A #N/A 5097.85 5095.20 Regression E n. 12.62 #N/A #N/A #N/A 5098.10 5095.20 Regression E n. 17.28 27.88 17.28 INLET 5098.35 5095.20 Regression E n. 22.62 29.43 22.62 INLET 5098.60 5095.20 Regression E n. 27.94 30.91 27.94 INLET 5098.85 5095.20 Regression E n. 32.94 32.33 32.33 OUTLET 5099.10 5095.20 Regression E n. 37.42 33.69 33.69 OUTLET 5099.35 5095.20 Regression E n. 41.46 35.00 35.00 OUTLET 5099.60 5095.20 Regression E n. 45.10 36.28 36.28 OUTLET 5099.85 5095.20 Regression E n. 48.44 37.51 37.51 OUTLET 5100.10 5095.20 Regression E n. 51.54 38.71 38.71 OUTLET 5100.35 5095.20 Regression E n. 54.44 39.88 39.88 OUTLET 5100.60 5095.20 Regression E n. 57.22 41.02 41.02 OUTLET 5100.85 5095.20 Regression E n. 59.82 42.12 42.12 OUTLET 5101.10 5095.20 Regression E n. 62.30 43.21 43.21 OUTLET 5101.35 5095.20 Regression E n. 64.70 44.26 44.26 OUTLET 5101.60 5095.20 Regression E n. 67.04 45.30 45.30 OUTLET 5101.85 5095.20 Regression E n. 69.30 46.31 46.31 OUTLET 5102.10 5095.20 Regression E n. 71.48 47.30 47.30 OUTLET 5102.35 5095.20 Regression E n. 73.62 48.28 48.28 OUTLET Processing Time: 00.16 Seconds MHFD-Culvert v4.0.)dsm,Culvert Rating 3/17/2023,3:07 PM MHFD-Cu/vert, Version 4.00(May2020) Project: Kimball Detention(Pond 315 Culverts) ID: STAGE-DISCHARGE CURVE FOR THE CULVERT 5103.6 5102.6 • o ❑ • p ❑ • - ❑ 5101.E ZAI El o ❑ ♦ o ❑ El j 5100.6 m (D ♦ ❑ w' ♦ ❑ m � as ♦ C ❑ R 5099.E ZL El ♦ 0 ❑ ♦ L ❑ ♦ T] 5098.E El zL ♦ ❑ o ♦ ❑ L ♦ ❑ 5097.E a 5096.E Z i 0 20 40 60 80 Discharge (cfs) i-Inlet Control 0 Outlet Control •Stage-Discharge MHFD-Culvert_v4.0.xlsm,Culvert Rating 3/17/2023,3:07 PM Stage Discharge Project Name: Polestar Subdivision: Polestar Project No.: 39797.01 Location: Fort Collins Calculated By: ARJ Checked By: Date: 3/15/2023 Q=C*L*H^1.5 C-2 7 Pond 315 Outlet Pond-Double Barrel Culvert Outlet L=Weir Length See Attached MHFD-Culvert_4.0 Spreadsheet H=Height Pond 315-24"Double Barrel Culvert Outlet Pond 315-Weir Discharge Elevation Stage(ft) Discharge(cfs) Energy Equation Elevation Stage(ft) Weir Length(ft) Discharge(cfs) 5096.60 0.00 0.00 No Flow(WS< inlet) 5100.40 0 0 0.00 5096.85 0.25 0.50 Min.Energy.Eqn. 5100.60 0.2 11.6 2.80 5097.10 0.50 2.32 Min.Energy.Eqn. 5100.80 0.4 15.3 10.45 5097.35 0.75 5.06 Min.Energy.Eqn. 5101.00 0.6 19.6 24.59 5097.60 1.00 8.68 Min.Energy.Eqn. 5101.20 0.8 24.3 46.95 5097.85 1.25 12.62 Regression Eqn. 5101.40 1 43.2 116.64 5098.10 1.50 17.28 INLET 5101.50 1.1 59.9 186.59 5098.35 1.75 22.62 INLET 5101.60 1.2 63.5 225.38 5098.60 2.00 27.94 INLET 5101.70 1.3 75.3 301.35 5098.85 2.25 32.33 OUTLET 5101.801 1.41 871 389.111 5099.10 2.50 33.69 OUTLET offset 3.8 feet from culvert invert at 5096.6 5099.35 2.75 35.00 OUTLET 5099.60 3.00 36.28 OUTLET 5099.85 3.25 37.51 OUTLET 5100.10 3.50 38.71 OUTLET 5100.35 3.75 39.88 OUTLET 5100.60 4.00 41.02 OUTLET 5100.85 4.25 42.12 OUTLET 5101.10 4.50 43.21 OUTLET 5101.35 4.75 44.26 OUTLET 5101.60 5.00 45.30 OUTLET 5101.85 5.25 46.31 OUTLET 5102.10 5.50 47.30 OUTLET 5102.35 5.75 48.28 OUTLET Appendix J-5 Flow Comparison r t N; I• ` v 'iei a � . •.. ' Mulberry Flow Path t • Path ` New Flow=463.3 �q Mulberry Flaw Path Mulberry FlawNew Flow=114:9 , �• %D+fference=57.1 New Flow=641.3 "' l` a 3 `Ya Difference=6A 9 °I Difference=28.3 k � Plum Flow Path New Flow=193.3 rl i 1. t r 1 'sl %Difference=49.8 PIUm FIawPalll -h� ! *'� a� i• �!.f _,,� ::ti: - _+ �z. Vt New Flaw=200.4 "' ' ' -: 'a tr• Plum Flow Path ° X-j ` Plum Flow Path %Differenc®-36.3 , + r �. -. .� New Flow_50.6 a New Flow=154-5 --- �" Plum Flaw Path 1 Plum Flow Path "t °!a D+fference=-4.5 Z %Difference=51.5 t New Flow=352.2 -' Plum Flow Path ! y 3t ,. New Flow=407 New Flow=434.6 R f Difference Q-11.3 '. % Difference=-16A (J� - t- - -- %Difference--13.4 Plum Flow Path New Flow=63.8 r �•, Difference < Ellzab@th FIOw Path .t 1 �l-~ F �v ' a- " New Flow=200-5 -Ai- r'x- LLJ I e Plum Flow Path r'�'e,. '+ �,r - ' rvt °le Difference=0.3 �SpOr 'r= - � 0 New Flaw 192 6 l. Clearuiew Flow Path _ f o Clearview Flow Path Difference=10 1 _ ., New Flow=257.8 New Flow-4d5.8 a i eiz.aa�ria t Elizabeth Flow Perth r` _r t 3ifift.' °re Difference--25.1 _ y - New Flow 10.5 �". LL J r A Differ@nce--4Q.1 �7� Plum Flaw Path ..3"utlt %Difference=101.9 ■ ..=i New Flow=354.9 1 Difference�-25.9 r i m k -, ►' ;.. Clearvlew Flow Path ll �- �, � _ yq - 3 ,• New Flow=426 " i Z o� to Clearvlew Flow Patty r {` �' - �; o Difference=-41 S Z +D New Flow=226.5 �" rl #3*ti - • - s .9 Canal Importation Flow Path {] °! Difference-6.3 � + 'u '� kW,' - _ LIZ - . Clearview Flaw Path 'e New Flow=521.9 �� .°�_: .'r New Flow-396.8 � '',.�v ,•� °Ja Difference--2.6 � W •" Clearview Flow Path .F " a %Difference=13 t° ,__. �'-!4 -,+ T .� Z „� _ Clearview Flaw Path : •a y - Z 6' a 1 New Flow=334.5 _ a w pgaSPE4FRB - �lrl ' !e03 - °1C1'6fferNew le Difference ow ��942.9 y '^ Difference •10.1 Ca �' `f •� 4, sr '-1 +•Vki ; �4 - . e ���. r - j. _ . �- -� _ �-�rCanal Importation Flow Path NewFlow_5"c6.1 Difference--2.441 Canal Impartation Flow Path New Flow_481.4 IZ Canal Impartatlan Flaw Path %Difference=0.7 W >,r : 5 ti,k New Flaw a°429.1 �" as %Difference--7.5 ' ! Canal Importation Flow at New Flow=256.7 f rb Difference=-9.9 t ' Canal Importation Flow Path �' r '•' l I. -- New Flow=718.7 artation Flow Path ' Canal Importation Flow Path IN analIm p as Difference=4+1.3 r W New Flaw=436.4 r• New Flaw=196,3 °f- Difference 6-6 � - ro.Difference=•3.3 +k" _- F.1 1r\l L }y,. 5 Feet ' �� ,..... r ^ r ' !. ii - i^6•bt'+a-... �__.x• _ �^r►�`.� Mldc 4 eat - � ��~ r�� sty .y • ��:. I'- s.o COFC2012.01_CI Basin Hydrologic Conversion_Report.docx 13 ANdERSON CONSU[TINCI ENGINEERS, INC. Table B.1.1 Plum Channel Flow Path Discharge Profile Discharge (cfs) HEC-Ras Sation EPA SWMM Element 100-year/Result to Description be Mapped 10-year 2-year 5271 113 241 67 10 Upstream Study Limit 4872 15 330 76 18 4277.999 115_pipe/115_overflow* 214 140 73 14 Upstream of Rocky Street Culvert 4277 115_pipe/115_overflow* 214/140 73 14 Rocky Street Culvert Overtopping 3993 16_pipe/16_overflow* 234/160 79 24 3816 16_pipe/16_overflow* 234/160 79 24 3544 116 221 70 13 2999.999 18_pipe/18_overflow* 377/349 117 46 Upstream of Gallup Road Culvert 2999 18_overflow 349 92 23 Gallup Road Overtopping 2661 18_pipe/18_overflow* 377/349 117 46 2570 118 375 116 46 1323 20 424 153 69 938 220-322 444 1 168 84 Upstream of Glenmoor Pond * Discharge based on the sum of pipe and overflow discharges Modified - Table B.1.1 Plum Channel Flow Path Discharge Profile Discharge(cfs) Effective HEC RAS-STATION EPA SWMM ELEMENT Effective HEC-RAS hydraulics model/Result Effective SWMM Hydrology model Corrected Effective Proposed Result Mapped by Anderson /Result Modeled /Result Modeled Location 5271 113(313out in CE models) 241 156 252 245 Upstream Study Limit 5190 NODE 23 --- --- --- 362 Pond Inflow 4872 (L)15 330 200 305 --- 4675 POND OUTFLOW J14 --- --- 174 Pond outflow 4277.999 C-1+115_pipe/115_overflow* 214/140 167/139 290/242 187/140 Upstream of Rocky Road Culvert 4277 C-1+115_pipe/115_overflow* 214/140 167/139 290/242 187/140 Rocky Road Culvert Overtopping 3993 C-1+16_pipe/16_overflow* 234/160 193/160 313/253 201/142 3816 C-1+16_pipe/16_overflow* 234/160 193/160 313/253 201/142 3544 (L)116 221 180 229 176 2999.999 18_pipe/18_overflow* 377/349 354/327 285/258 285/257 Upstream of Gallup Road Culvert 2999 18_overflow 349 327 258 257 Gallup Road Overtopping 2661 18_pipe/18_overflow* 377/349 354/327 285/258 285/257 2570 (L)118 375 352 284 281 1323 (L)20 424 406 356 356 938 (L)220-322 1 444 1 434 1 391 1 390 lUpstream of Glenmoor Pond *Discharge based on the sum of pipe and overflow discharges Flow is presented as(total flow)/(Surface Flow) ---null value XXXX-New Station or Element Modeled Appendix J-6 Spillway Variance Request Stormwater Alternative Compl ianceNariance Application City of Fort Collins Water Utilities Engineering Section • • • Engineer Name Joseph M. Frank Phone 303.267.6232 Street Address 2900 South College Avenue, Ste. 3D City Fort Collins state CO Zip 80525 Owner Name Michael Gornik Phone 808.443.9956 Street Address PO Box 271582 City Fort Collins state CO Zip 80521 Section B: Proposed Project Information Project Name Polestar Village Project/Application Number from Development Review (i.e. FDP123456) PDP220010 Legal description and/or address of property POLESTAR VILLAGE FILING NO. 1 A PARCEL OF LAND BEING A PORTION OF THE NORTHWEST QUARTER OF SECTION 16,TOWNSHIP 7 NORTH,RANGE 69 WEST OF THE 6TH PRINCIPAL MERIDIAN,CITY OF FORT COLLINS,COUNTY OF LARIMER,STATE OF COLORADO Description of Project Mixed use residential and commercial Existing Use (check one): C' residential ('' non-residential C mixed-use (*-' vacant ground Proposed Use (check one): (" residential (' non-residential (*- mixed-use C other If non-residential or mixed use, describe in detail Mixed used Multi-family, residential, commercial, w/ a recreation center and temple. SectionInformation State the requirement from which alternative compliance/variance is sought. (Please include applicable Drainage Criteria Manual volume, chapter and section.) 2018 City of FCSCM Chapter 8, Section 3.4 Freeboard and Section 3.5 Spillway Max Flow Depth What hardship prevents this site from meeting the requirement? See attached letter. Attach separate sheet if necessary What alternative is proposed for the site? See attached letter. Attach separate sheet if necessary page 2 The owner agrees to comply with the provisions of the zoning ordinance, building code and all other applicable sections of the City Code, Land Use Code, City Plan and all other laws and ordinances affecting the construction and occupancy of the proposed building that are not directly approved by this variance. The owner understands that if this variance is approved, the structure and its occupants may be more susceptible to flood or runoff damage as well as other adverse drainage issues. Signature of owner: _Date: a3 9/4 The engineer hereby certifies that the above information, along with the reference plans and project descriptions is correct. j nature of engineer: Date: Signature g - �,Jk fl_LI��Fy o PE53399 J�aNAL V PE STAMP Date complete application submitted: Date of approval/denial: __Variance: ❑ approved ❑ denied Staff justification/notes/conditions: Approved by: Entered in UtilityFile Database? ❑yes ❑no If VOLI have questions or - out forms, • Fort Collins Utilities a't: Phone: i i! fi9/0-224-6003 City of fcgov.com/stormvlater - Emai • • Fort • �3th J•R ENGINEERING 50 YEARS OF EXCELLENCE VARIANCE REQUEST Date: November 181h 2024 From: Joseph Frank, PE Subject: Scenic Views and Polestar Spillway Variance Request I am writing to request a variance from the 2018 Stormwater City of Fort Collins criteria regarding the spillway requirements for Scenic Views Pond and Polestar/Happy Heart Detention pond. Specifically, the variance is for: Chapter 8, Section 3.4—Free Board • Twelve inches (12") of freeboard is to be provided within the detention basin, measured vertically from the 100-year water surface elevation to the top of the basin, or measured from the emergency spillway elevation(if it is higher than the 100-year water surface elevation) to the top of the basin. Chapter 8, Section 3.5—Spillway Max Flow Depth • Emergency overflow depth shall be no more than six inches (6") at the crest during the 100-year storm. The Scenic Views Pond and Polestar/Happy Heart Detention pond are located in the City of Fort Collins floodplain termed"Plum Street Flow Path" Scenic View Pond Spillway Existing condition for Scenic Views Pond: The existing spillway has a depth of 1.5 feet and width of 10 feet. The existing spillway elevation is at (5115.57 on the NAVD 88 datum) and (5112.5 on the NVGD 29 datum). The flow from the pond (349 cfs = peak pond inflow per corrected effective SWMM model) surpasses the capacity of the spillway,causing it to overflow and overtops the embankment at an approximate depth of 2.02 feet. The water then spills over the eastern portion of the retention pond for a distance of approximately 290 ft, see existing Scenic Views pond spillway section in Appendix A.1. Proposed condition: JR Engineering is proposing to modify the overflow spillway while maintaining the existing spillway elevation of 5115.57 as to not impact volume within the pond. The proposed spillway has a crest length of 51 feet and will result in an overflow depth 1.75 feet at 349 cfs, which exceeds the city's required depth of six inches. See the scenic views spillway improvement section in Appendix A.1. Justification for Variance: The proposed improvements are intended to increase the emergency overflow spillway capacity and improve the existing spillway by providing additional riprap protection. This modification will decrease the overall breadth of the floodplain, reduce the emergency overflow depth from 2.02 feet to 1.75 feet and serve as an improvement to the existing scenic views retention pond. The proposed Finished Flood Elevations (FFE) of the building directly downstream of the Scenic Views Retention facility will be set at 18-inches above the proposed base flood elevation The spillway variance is necessary to ❑ 7200 South Alton Way ❑ 25188 Genesee Trail Road ❑ 5475 Tech Center Drive ❑ 2900 South College Avenue Suite C400 Suite 110 Suite 235 Suite 1A Centennial,CO 80112 Golden,CO 80401 Colorado Springs,CO 80919 Fort Collins,CO 80525 303-740-9393 9 Fax 303-921-7320 303-740-9393 9 Fax 303-921-7320 719-593-2593 9 Fax 303-921-7320 970-491-9888•Fax 303-921-7320 �3th j-R ENGINEERING 50 YEARS OF EXCELLENCE increase the emergency capacity and prevent overtopping of the existing embankment. Please refer to exhibits and calculations in Appendix A.1 for additional information. Polestar Detention Pond Spillway Proposed Polestar/Happy Heart Farms Spillway: The proposed spillway has a crest length of 36.8 feet and will result in an overflow depth 2.21 feet at 362 cfs (peak pond inflow per proposed SVOAM model), which exceeds the city's required depth of six inches. This spillway is intended to remain in place when the ultimate regional pond is constructed which will result in an overflow depth of 1.61 feet at 221 cfs. See the Polestar detention facility spillway section in Appendix B.1. Justification for Variance: The request is to allow for the same approach as the Concept Canal Importation Master Plan for the ultimate condition by Jacobs and prevent the flow from the emergency spillway from being directed towards existing structures and homes downstream. By narrowing the spillway and allowing the overflow depth to exceed six inches, the spillway will better direct flows between houses and towards the improvements in the drainage easement to the east of the Polestar development. Refer to exhibits and calculations in Appendix B.1 for additional 'information. ❑ 7200 South Alton Way ❑ 25188 Genesee Trail Road ❑ 5475 Tech Center Drive ❑ 2900 South College Avenue Suite C400 Suite 110 Suite 235 Suite 1A Centennial,CO 80112 Golden,CO 80401 Colorado Springs,CO 80919 Fort Collins,CO 80525 303-740-9393 9 Fax 303-921-7320 303-740-9393 9 Fax 303-921-7320 719-593-2593 9 Fax 303-921-7320 970-491-9888•Fax 303-921-7320 �3th J•R ENGINEERING 50 YEARS OF EXCELLENCE Appendix A. l ❑ 7200 South Alton Way ❑ 25188 Genesee Trail Road ❑ 5475 Tech Center Drive ❑ 2900 South College Avenue Suite C400 Suite 110 Suite 235 Suite 1A Centennial,CO 80112 Golden,CO 80401 Colorado Springs,CO 80919 Fort Collins,CO 80525 303-740-9393 9 Fax 303-921-7320 303-740-9393 9 Fax 303-921-7320 719-593-2593 9 Fax 303-921-7320 970-491-9888•Fax 303-921-7320 x r- W - - - - -- W - -1.06� - - - - l 1.06. lo STILLING BASIN SCENIC VIEWS SPILLWAY E \` rl+FI ,` SCENIC VIEWS RETENTION POND � 'wt �< 51g5 POLESTAR DETENTION POND M POLESTAR SPILLWAY' �A3o Asp ,� ,� , I� 1 \ o J-- A3 A3 A3 As A3 Aso li ^ TE m m m v 100 50 0 100 ORIGINAL SCALE: 1" = 100' UF—FL2ILI h to PROPOSED GRADING POLESTAR JOB NO. 3979701 11/18/2024 SHEET 1 OF 1 J-R ENGOMMUNG A Westrian Company C *rn M 303-740--M•Cdoido*IVS 719-5 20 Fort Coin 970-491-M•WWW' EXISTING SCENIC VIEWS - SPILLWAY TOTAL LENGTH 290.00' TOTAL INFLOW INTO THE POND = 348.6 CFS APPROXIMATE DEPTH 2.0 FT WSEL BASE ON 100-YR PEAK INFLOW RATE. (NO ATTENUATION PER CRITERIA) BERM ELEV=5117.07 DEPTH OVER EMBANKMENT 0.5 FEET BERM ELEV=5117.07 =1 I=1 I=1 1= 1= 1= 1= 1= 1= 1= 1= 1= 1= 1= 1= I o ____ = 1 = 1 = 1 = 1 = 1 = 1 = 1 = 1 I—I= 1 = 1 = 1 = 1 = 1 = _ = WEIR EELV=5115. n = _ _ _ _ Hill 100 YEAR EMERGENCY OVERFLOW FROM JR CE SWMM MODEL = 252 CFS APPROXIMATE DEPTH 1.9 FT 3.75' 10.00' 3.75' WSEL BASED ON ROUTED 100-YEAR POND OUTFLOW RATE EXISTING SPILLWAY CAPACITY UNDER DEPTH OVER EMBANKMENT 0.4 FEET EMBANKMENT - 47.8 CFS EX. SCENIC VIEWS - SPILLWAY 6 3 0 6 12 POLESTAR JOB NO. 3979701 03/20/2023 ORIGINAL SCALE: 1" = 6' SHEET 1 OF 1 4V J'R ENGOMERING A Westrian Company Fart Cain 970-491-W•www SCENIC VIEWS - SPILLWAY IMPROVEMENT TOTAL INFLOW INTO SCENIC VIEWS POND IN SWMM 348.65 OVERFLOW MODELED IN SWMM WHEN SCENIC VIEWS POND 100 YEAR EMERGENCY OVERFLOW = 348.65 CFS IS 100% FULL W/ A FLOW DEPTH OF 1.75 FT AND 0.5 FEET OF FREE BOARD 1.40 FT DEEP AT 244.76 CFS WSEVV BASED ON 100-YR PEAK INFLOW RATE (NO ATTENUATION PER CRITERIA) 0.85 FEET OF FREEBOARD WSEVL BASED ON ROUTED 100-YR POND OUTFLOW RATE BERM ELEV=5117.82 BERM ELEV=5117.82 W.S ELEV=5117.32 2.5 .51 = W.S ELEV=5116.97 1 — r�WEIR ELEV=5115.57� oO oO oO 0 I oOn n crl rMIN 171 5.63' 51.00' TYPE M RIP RAP © 2' DEPTH 5.63' TOP SOIL TYPE II BEDDING 1' THICKNESS SCENIC VIEWS - SPILLWAY 6 3 0 6 12 POLESTAR JOB NO. 3979701 11/15/2024 ORIGINAL SCALE: 1" = 6' SHEET 1 OF 1 10 J-R ENGOMMIRING A Westrian Company Centerriial 303-740--M•CobMdo Strips M-M-2590 Fort Coins 9M 491-M•www' Scenic Views Pond Broad Crested Weir Project Description Solve For Crest Length Input Data Discharge 348.61 cfs Headwater Elevation 5,117.32 ft Crest Elevation 5,115.57 ft Tailwater Elevation 0.00 ft Crest Surface Type Gravel Crest Breadth 20.00 ft Results Crest Length 51.0 ft Headwater Height Above 1.75 ft Crest Tailwater Height Above Crest -5,115.57 ft Weir Coefficient 2.95 ft^(1/2)/s Submergence Factor 1.000 Adjusted Weir Coefficient 2.95 ft^(1/2)/s Flow Area 89.3 ftz Velocity 3.90 ft/s Wetted Perimeter 54.5 ft Top Width 51.02 ft Bentley Systems,Inc. Haestad Methods Solution FlowMaster Scenic Views Pond.fm8 Center [10.03.00.03] 2/9/2023 27 Siemon Company Drive Suite 200 W Page 1 of 1 Watertown,CT 06795 USA +1-203-755-1666 Chapter 12 Storage CREST OF EMERGENCY SPILLWAY EMBANKMENT WIDTH EMERGENCY OVERFLOW WSEL FLOW BEYOND TOP OF 100-1EAR WSEL �'� EMBANKMENT DETENTION Z3 BASIN >F 1 1 3' MIN 1' MIN SOIL RIPRAP 2D5o FREEBOARD TOP OF FOOTING AT OR BELOW EXTENDED RIPRAP BOTTOM OF SOIL RIPRAP LPSTREAM OF WALL CONCRETE OVERFLOW WALL (WALL AND REINFORCING DESIGNED BY ENGINEER) EMERGENCY SPILLWAY PROFILE AS NEEDED TO PASS THE IC0-"R UNDETAINED OR MORE 3" TO 4" EMERGENCY OVERFLOW WSEL 1' MIN TOPSOIL COVER FREEBOA3D CREST OF EMERGENCY SPILLWAY Z 2.5 SOIL RIPRAP 20yp EMERGENCY SPILLWAY SECTION AND SPILLWAY CHANNEL 35 30 - . - . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 ac . . . . . . _ . . . - - . . . . . . - . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e20 . .. . . . . .- . . . . . . - . . . - . . . . . . . . - . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . - --- . . . . . s TYPE H TYPE 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 g — . . . . . . - - - - - - - . . . . . . . . . . . . . . . . .. - . . . . . . . . . . . . . . . . 0 0 5 10 15 20 25 30 Unit Discharge(cfs/ft) Figure 12-21. Embankment protection details and rock sizing chart(adapted from Arapahoe County) September 2017 Urban Drainage and Flood Control District 12-33 Urban Storm Drainage Criteria Manual Volume 2 �3th J•R ENGINEERING 50 YEARS OF EXCELLENCE Appendix B. 1 ❑ 7200 South Alton Way ❑ 25188 Genesee Trail Road ❑ 5475 Tech Center Drive ❑ 2900 South College Avenue Suite C400 Suite 110 Suite 235 Suite 1A Centennial,CO 80112 Golden,CO 80401 Colorado Springs,CO 80919 Fort Collins,CO 80525 303-740-9393 9 Fax 303-921-7320 303-740-9393 9 Fax 303-921-7320 719-593-2593 9 Fax 303-921-7320 970-491-9888•Fax 303-921-7320 POLESTAR DETENTION FACILITY - SPILLWAY TOTAL FLOW INTO THE POND IN SWMM IN THE INTERIM PROPOSED CONDITION 361.8 CFS TOTAL FLOW INTO POND IN SWMM IN THE ULTIMATE CONDITION 221.2 CFS 100 YEAR EMERGENCY OVERFLOW = 361.8 CFS 100 YEAR EMERGENCY OVERFLOW = 221.2 CFS W/ A FLOW DEPTH OF 2.21 FT W/ A FLOW DEPTH OF 1.61 FT FREEBOARD 0.50 FT 1.13 FT OF FREE BOARD PROVIDED WSEL BASE ON 100-YR PEAK INFLOW RATE. WSEL BASE ON 100-YR PEAK INFLOW RATE. (NO ATTENUATION PER CRITERIA) (NO ATTENUATION PER CRITERIA) 50.50' TOTAL WIDTH 48.00' AT FLOW DEPTH BERM ELEV=5110.50 W.S ELEV. INTERIM PROPOSED=5110.00 I BERM ELEV=5110.50 5 - 2.5 — - a 1 W.S ELEV. ULTIMATE CONDITION=5109.40 - 1r� Q — — TOTAL DEPTH 2.71 FT Oo�O O� ram., n r�- r� n rJ O� O� O� OF\ pO� — SIZED FOR ULTIMATE CONDITION WITH O WEIR ELEV=5107.79 O O O O AT LEAST 6 INCHES OF FREEBOARD 4" MIN. TOP S01 L Q O QOD O COVER _ I TYPE II BEDDING_ TYPE H RIP RAP © 3' DEPTH - = 1 THICKNESS 6.85' 36.80' 6.85' 3" TOPSOIL COVER ONSITE — SPILLWAY DETAIL 6 3 0 6 12 POLESTAR JOB NO. 3979701 11/15/2024 ORIGINAL SCALE: 1" = 6' SHEET 1 OF 1 10 J-R ENGOMMIRING A Westrian Company Centerriial 303-740--M•CobMdo Strips M-M-2590 Fort Coins 9M 491-M•www' Polestar Interim Broad Crested Weir - 1 Project Description Solve For Headwater Elevation Input Data Discharge 361.80 cfs Crest Elevation 5,107.79 ft Tailwater Elevation 0.00 ft Crest Surface Type Gravel Crest Breadth 25.00 ft Crest Length 36.8 ft Results Headwater Elevation 5,110.00 ft Headwater Height Above 2.21 ft Crest Tailwater Height Above Crest -5,107.79 ft Weir Coefficient 2.99 ft^(1/2)/s Submergence Factor 1.000 Adjusted Weir Coefficient 2.99 ft^(1/2)/s Flow Area 81.3 ftz Velocity 4.45 ft/s Wetted Perimeter 41.2 ft Top Width 36.80 ft Bentley Systems,Inc. Haestad Methods Solution FlowMaster Polestar Pond.fm8 Center [10.03.00.03] 8/23/2023 27 Siemon Company Drive Suite 200 W Page 1 of 1 Watertown,CT 06795 USA +1-203-755-1666 Ultimate Polestar - Broad Crested Weir Project Description Solve For Headwater Elevation Input Data Discharge 221.20 cfs Crest Elevation 5,107.79 ft Tailwater Elevation 0.00 ft Crest Surface Type Gravel Crest Breadth 25.00 ft Crest Length 36.8 ft Results Headwater Elevation 5,109.40 ft Headwater Height Above 1.61 ft Crest Tailwater Height Above Crest -5,107.79 ft Weir Coefficient 2.93 ft^(1/2)/s Submergence Factor 1.000 Adjusted Weir Coefficient 2.93 ft^(1/2)/s Flow Area 59.4 ftz Velocity 3.73 ft/s Wetted Perimeter 40.0 ft Top Width 36.80 ft Bentley Systems,Inc. Haestad Methods Solution FlowMaster Polestar Pond.fm8 Center [10.03.00.03] 8/23/2023 27 Siemon Company Drive Suite 200 W Page 1 of 1 Watertown,CT 06795 USA +1-203-755-1666 Chapter 12 Storage CREST OF EMERGENCY SPILLWAY EMBANKMENT WIDTH EMERGENCY OVERFLOW WSEL FLOW BEYOND TOP OF 100-1EAR WSEL �'� EMBANKMENT DETENTION Z3 BASIN >F 1 1 3' MIN 1' MIN SOIL RIPRAP 2D5o FREEBOARD TOP OF FOOTING AT OR BELOW EXTENDED RIPRAP BOTTOM OF SOIL RIPRAP LPSTREAM OF WALL CONCRETE OVERFLOW WALL (WALL AND REINFORCING DESIGNED BY ENGINEER) EMERGENCY SPILLWAY PROFILE AS NEEDED TO PASS THE IC0-"R UNDETAINED OR MORE 3" TO 4" EMERGENCY OVERFLOW WSEL 1' MIN TOPSOIL COVER FREEBOA3D CREST OF EMERGENCY SPILLWAY Z 2.5 SOIL RIPRAP 20yp EMERGENCY SPILLWAY SECTION AND SPILLWAY CHANNEL 35 30 - . - . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 ac . . . . . . _ . . . - - . . . . . . - . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e20 . .. . . . . .- . . . . . . - . . . - . . . . . . . . - . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . - --- . . . . . s TYPE H TYPE 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 g — . . . . . . - - - - - - - . . . . . . . . . . . . . . . . .. - . . . . . . . . . . . . . . . . 0 0 5 10 15 20 25 30 Unit Discharge(cfs/ft) Figure 12-21. Embankment protection details and rock sizing chart(adapted from Arapahoe County) September 2017 Urban Drainage and Flood Control District 12-33 Urban Storm Drainage Criteria Manual Volume 2 �3th J•R ENGINEERING 50 YEARS OF EXCELLENCE Appendix C. l ❑ 7200 South Alton Way ❑ 25188 Genesee Trail Road ❑ 5475 Tech Center Drive ❑ 2900 South College Avenue Suite C400 Suite 110 Suite 235 Suite 1A Centennial,CO 80112 Golden,CO 80401 Colorado Springs,CO 80919 Fort Collins,CO 80525 303-740-9393 9 Fax 303-921-7320 303-740-9393 9 Fax 303-921-7320 719-593-2593 9 Fax 303-921-7320 970-491-9888•Fax 303-921-7320 From: Theodore Bender <tbender@fcgov.com> Sent: Monday, May 1, 2023 5:11 PM To: Joey Frank;Andrew Joyce; Kenneth Merritt Cc: Heidi Hansen; Dan Mogen; Matt Simpson; Ken Sampley Subject: Polestar Variance Response Attachments: Downstream Structures.jpg Hello JR Team, Thank you for your patience as we work through this variance request. During our review, it came to our attention that the correct minimum freeboard requirement at the spillway may not be the "6-inches"that we had been discussing, but potentially 12-inches. This requirement is based on the need to provide 12-inches of freeboard from the (primary) 100- year WSEL to the top of embankment(please see Chapter 8, Section 3.4, 15Y bullet of the City 2018 Stormwater Criteria Manual). Typically, a detention pond overflow spillway is the secondary outlet with the primary outlet being a pipe at lower stage. The only outlet from the Scenic View Pond is the overflow spillway. This situation created the need for additional internal discussion and did slow down our response. We understand the Polestar development project would improve the Scenic View spillway and we have taken this into consideration. We'd like to emphasize that currently there are no residential structures located directly below this spillway. It is our understanding the Polestar development would like to place residential structures directly below (to the north and south)the primary Scenic View spillway. This has been the main driver in our internal discussion to maintain safety for the future residents of this site. The result of our internal discussion is that City staff has agreed the 12-inches of freeboard, above the overflow WSEL, will not be required. Instead,we like to ask these structure directly below the Scenic View spillway be elevated in relation to their adjacent BFE. Here is our response for the two detention ponds: Polestar Pond (Happy Heart/Eastern pond) The 6-inches of freeboard at this pond measured from the 100-yr WSE to the top of the pond embankment is approved. The main concern at this pond is that we not direct flow from the emergency spill towards any existing downstream structures. As we discussed in the past,we asked our master planning consultant to narrow up the conceptual design weir cross-section for this reason. The full master planned improvement at this location also includes an outlet pipe that would run beneath Orchard Place to the north. The proposed Polestar spillway weir dimensions are acceptable if the hydraulics show these existing downstream structures are not impacted. As a part of the hydraulics phase of the CLOMR, please focus on this area and provide a figure to show these downstream structures will not be impacted. An additional cross-section (or two) may be needed and appropriately placed to provide confidence in the floodplain and floodway width in this area. If the CLOMR hydraulics show the proposed Polestar spillway weir dimensions direct flow towards these existing downstream structures, we would ask that it be modified and remodeled. Thank you for including the stability and potential erosion to this spillway section in your analysis. From the CLOMR hydraulics study,we plan to review the flow depths and velocities in this area to make sure the proposed solution is able to protect the area from excessive erosion. Scenic Views Pond (Western pond) City staff discussed the freeboard at the Scenic View Pond in detail. I understand from your email last week you no longer wish to pursue a variance request at this location. Please send us a spillway cross-section similar the eastern pond to show the 100-yr WSE,freeboard, and associated elevations of the crest and berm. The 6-inches of freeboard suggested at this pond measured from the 100-yr WSE to the top of the pond embankment is 1 acceptable. As mentioned above, we would like to ask your team to provide 18-inches of freeboard from the highest adjacent BFE for the structures immediately east(downstream) of the Scenic View pond (image attached). This BFE would be developed by your team as a part of the upcoming hydraulics portion of the CLOMR. Because these structures will be placed downstream of the primary outlet to this pond,we feel this level of flood risk reduction is necessary. Our decision is grounded in public safety and the safety of the new residents downstream of this spillway. As with the eastern pond,thank you for including the stability and potential erosion to this weir section for the Scenic View Pond in your analysis. We will review this as well with the hydraulics portion of the CLOMR. Again,thank you for your patience. I know this timeline has not been ideal for your client. This is a complicated project in a high flood risk area. This project is more complicated than other CLOMR requests;this CLOMR proposal is to change both the hydrology and hydraulics for this site,while most CLOMRs only propose to change the hydraulics. Please reach out if you'd like to discuss. We are happy to chat further. -TRB Theodore R.Bender,PE,CFM Stormwater Engineering Manager Master Planning and Floodplain Management of Fart Collins 14ff�"I'e1Fd'�Ef 700 Wood Street Fort Collins, CO 80522-0580 (970) 221-6503 tbender@fcgov.com 2 �3th J•R ENGINEERING 50 YEARS OF EXCELLENCE Appendix D. l ❑ 7200 South Alton Way ❑ 25188 Genesee Trail Road ❑ 5475 Tech Center Drive ❑ 2900 South College Avenue Suite C400 Suite 110 Suite 235 Suite 1A Centennial,CO 80112 Golden,CO 80401 Colorado Springs,CO 80919 Fort Collins,CO 80525 303-740-9393 9 Fax 303-921-7320 303-740-9393 9 Fax 303-921-7320 719-593-2593 9 Fax 303-921-7320 970-491-9888•Fax 303-921-7320 July 26,2023 Polestar Gardens,Inc 850 S Overland Trail,#15 Fort Collins,CO RE. Letter of Intent for casements for rateni on pond anpruvtown"tzsr Final easement documents will be reviewed by an attorney for Saddle Ridge commory Cor;drmfr': Association. Dear Development Review Coordinator: The Saddle Ridge Commons Condominium Association is the owner of Tract A that abuts' Village Property.We understand that as part of the Polestar Gardens development project,e.eE (Polestar Gardens)will be required to make Improvements to the existing retention pond.:tde f5ac: Ridge Commons)agree to work with Polestar to obtain the needed easements for these tmproverner`4 pending approval from the Association's attorney. Sincerely, The Board of directors Saddle Ridge Commons Condominium Association Signature -- 'c Date 23 APPENDIX F - MAPS BASIN SUMMARY TABLE77- FLUIVIbiz v, Z U) LU z i I Tributary Area Percent t2 t100 Q2 Q1oo Q Q � w w w \ wwz � o' ` Sub-basin (acres) Impervious C2 C100 (min) (min) (cfs) (cfs) w to w z 10. I Wiz } wwmz ^• �0 17W I I I c� o' w - ORCHARD PL = � M -5 1 O Al 1.02 16% 0.31 0.39 11.0 11.0 0.7 3.0 I c� QOQ �cnoLU LOCUST GROVE I I A 2 0.58 5 2/ 0.60 0.74 7.0 5.0 0.9 3.8LIU L 7 ® ` THIRD FILING I I o J0 � � z � )- 0 = A3 0.78 25/ 0.39 0.49 7.0 5.0 0.8 3.4 � [MIS z = wwc� wzwz 5120 I I I wwwww � � � II A4 1.23 65% 0.70 0.87 7.0 5.0 2.2 9.4 � � QQQQ = 0Q 0 �[ +x I I I I I A5 0.42 57% 0.65 0.82 7.0 5.0 0.7 3.0 X I ­j I I A6 1.03 69% 0.72 0.90 7.0 5.0 1.9 8.1 w I � ul 11-J I I I I 0 (••) N / I 5115 VI I - - I A7 0.85 63% 0.67 0.84 7.0 5.0 1.4 6.3 Zwl( Ln Ln 11 i 24 ,z j CO ; I - O A8 0.58 84% 0.84 1.00 7.0 5.0 1.2 5.1 �/ I Ln ° j00 1 I V � � ,�\ 1I � Jk A9.1 0.16 84% 0.87 1.00 7.0 5.0 0.3 1.4 I 0 wLn0 � O � p II � U � J h- - - - A9.2 0.03 54% 0.80 1.00 7.0 5.0 0.1 0.3 p I I I N rn - - - - 5910 1 A10 0.09 85% 0.88 1.00 11.0 11.0 0.2 0.7 � Q I I - - - - - - - - - - - W. ORCHARD PL. 1.70% -- 5- - - _ - -_ - 61, = _ - - - - ELIZABETE- T Q O J I I -(�} - S - - - - S -© All 0.13 69% 0.74 0.92 11.0 11.0 0.2 0.9 W Q m O ---- - -_ - - - - - - - _ W. ORCHARD PLC; - o � = - - - 00 51 C�00 i /' _ _ A 12 0.26 34% 0.45 0.56 11.0 11.0 0.2 1.1 CD - - - - - - - - m - mhow 5109.40 =_ �_� = - A 13 0.40 61% 0.70 0.87 11.0 11.0 0.6 2.6 KEY MAP (j C 00 zz� - - - - - - + - - - - x - - - - - - - 'S11 / SCALE: NTS W 0- I o raj I ` \J f\ (i � - - 'x 1\ A14 0.09 21% 0.32 0.41 11.0 11.0 0.1 0.3 00 p' o / o A 15 0.49 24% 0.33 0.42 11.0 11.0 0.4 1.5 Io o I O Q I -C J \ �� / _ - A16 0.12 51% 0.55 0.69 11.0 11.0 0.1 0.6 -- - - - - - - - - I i/ I - A17 0.43 30% 0.43 0.53 11.0 11.0 0.4 1.7 LEGEND 6'100 EXISTING MAJOR CONTOUR A 18 0.72 46% 0.53 0.66 11.0 11.0 0.8 3.5 313 o cnWiMp `✓ 5110 a % 5110 1X Q s, - � 7 100 _Z ` \` � A19 0.35 52% 0.59 0.74 7.0 5.0 0.5 2.2 - - - - - - - \ SCENIC (%rc WS a • 5105 �O O EXISTING INTERMEDIATE CONTOUR �,, POND '• .t-. . 511 i n 8 \ 1� / \) /i B1 1.23 50% 0.59 0.73 11.0 11.0 1.5 6.7 fi100 PROPOSED MAJOR CONTOUR E : .. .. o ' '•":��'tiff ' 1110.81 0,5 B2 0.31 78% 0.80 0.99 11.0 5.0 0.5 2.3 \ 1028� ,.�"= a`t` ` 23 '� - JFinwy �D I Cl0.28 47% 0.58 0.73 5.0 5.0 0.5 2.0 PROPOSED INTERMEDIATE CONTOUR \ � Q � SEE SHEET 35 FLD 510 - \ 1 �� -�-,=r I C2 0.32 31% 0.44 0.55 10.0 9.0 0.3 1.4 OO EXISTING STORM SEWER/RCP 5110 lye` I - 5105 - 5105 _ D1 0.35 64% 0.66 0.83 10.0 10.0 0.5 2.3 .�' • PROPOSED STORM SEWER/RCP 31% POLESTAR DETENTION POND - ' 1i � �.� \�l�J 1\ D2 0.22 63% 0.68 0.85 11.0 9.0 0.3 1.4 o `S,'0 / oh o FL �0 1 J 11, � j 1 / D3 0.16 70% 0.73 0.92 10.0 7.0 0.3 1.2 PROPOSED SWALE a h _ G TE � Q � - \ r I � � I `n 100 , I II \ 1 0 / I � � !, \`� yl�I r r / ) D4 0.25 610% 0.65 0.82 10.0 10.0 0.4 1.6 A BASIN IDg4 T_17 � - - ` D5 0.29 67/ 0.71 0.89 11.0 7.0 0.4 1.9 A: BASIN DESIGNATION I 1.82% L o /J \ 1 ° B C B: AREA (AC) D6 0.28 60/ 0.65 0.81 12.0 9.0 0.4 1.6 �, / �� ~� / ° C: % IMPERVIOUS ¢ E ,�, - - / p I 1 1 / D7 0.11 85/ 0.86 1.00 9.0 5.0 0.2 0.9 m rn \ SJ Ds co - - o FLD o �O ` l ) / D8 0.19 90% 0.89 1.00 8.0 5.0 0.4 1.6 _5 \ DRAINAGE DISCHARGE � L �� � cr / 1 I c \ / El 2.24 41% 0.51 0.64 14.0 14.0 2.2 9.6 1 o E2 0.54 54% 0.60 0.75 12.0 12.0 0.7 2.9 DESIGN POINT o o \ � ~ \ 1 I / E3 0.31 59/ 0.64 0.80 11.0 11.0 0.4 1.9 5105 J 1 v ° ► PROPOSED FLOW DIRECTION � \ _ 1 \\ � o � 2•17%� � � .. ) a � K- ( (�j _ � �_ F1 3.92 31% 0.45 0.56 13.0 13.0 3.5 15.1 � � � � � BASIN DRAINAGE AREA \ \ � Iv- S>> 5110 1� � / / �/J OS1 0.61 15% 0.31 0.39 11.0 11.0 0.4 1.8 r 511- o 4 0 \ ( 0.59 0.73 11.0 11.0 0.1 0.5 � �g OS2 0.09 51/ x \ Q 4 \ � ' Lri - b�- - / ` (^\� I 1 �' I ( �/=� POND w / V` \� �� D R V l I � �� / / Design Point Table p � III I II I� �, Tributary Q2 Q100 - - - V I IIC�� <� DP (cfs) (cfs) m / v I SUMMARY INFO. NOTES. POLESTAR INTERIM POND IS FOR FLOOD SITE IS GREATER THAN 20 ACRES. 1.1 1.2 5.2 CONTROL AND TREATS WATER QUALITY. 1 I I f \ 1.2 3.1 13.4 THE RATIONAL METHOD HAS BEEN USED TO ) I �J I I \ 15.0 STATUTE§ 37-92-602 8 . SIZE INDIVIDUAL STORM PIPES AND DRAINS. � ° o o � I POND MEETS COLORADO STATE DRAIN TIME 1.4 3.9 17.0 IN THE EXISTING RUNOFF FROM THE POLESTAR APPENDIREFER X EWOFM THE P DRAINAGE DREPORT FOR 86g ^ y - _ _ __ 1.5 8.0 34.5 SITE IS AT 33.1 CFS IN THE 100 YEAR EVENT. ADDITIONAL INFORMATION ON INFLOWS IN AND W. PLUM STD 1.6 8.5 36.6 OUT OF SITE AND INFORMATION REGARDING / THE RELEASE RATE FROM THE POLESTAR SITE W PLUM ST `/ NOT INCLUDING OFFSITE FLOW IS 28.8 CFS IN OFFSITE BASINS AND HISTORIC BASINS. THE 100 YEAR EVENT. I / ° 3.1 1.3 5.5 �� r' �, o I THE RELEASE RATE WITH OFFSITE AND ONSITE O _ 1 I 1 4.1 1.1 4.8 _� r, "� I ,x RUNOFF IS 174 CFS. �► o I 1 I � 1V< � C\� . 4.2 1.8 8.2 NOTES / o N s ! l O 4.3 2.0 9.2 z ; % 1 989 1.42% / I ( I ( / 10a 0.2 0.9 THIS PROPERTY IS LOCATED WITHIN A CITY REGULATED 100-YEAR CANAL o IMPORTATION FLOODPLAIN AND FLOODWAY AND MUST COMPLY WITH � II / 11a 0.2 1.2 CHAPTER 10 OF THE CITY MUNICIPAL CODE. Ld Ld 8%,SEE SHEET ?cam x , 'ate' J i� \�� e RESIDENTIAL USES IN THE 100-YEAR FLOODPLAIN MUST BE ELEVATED 12a 1.4 6.2 ABOVE THE REGULATORY FLOOD PROTECTION ELEVATION. RESIDENTIAL USES 13a 0.7 3.5 ARE PROHIBITED WITHIN THE FLOODWAY. o `V' �' /� > I I ` \ `-� A FLOODPLAIN USE PERMIT IS REQUIRED FOR ANY WORK WITHIN THE z 14a 1.0 4.3 100 YEAR FLOODPLAIN. A NO RISE CERTIFICATION IS REQUIRED FOR ANY � , �� r WORK WITHIN THE FLOODWAY. N x\I 2• x � (J 11 I I / / / / 15a 0.9 4.2 CRITICAL FACILITIES ARE PROHIBITED WITHIN THE 100-YEAR FLOODPLAIN. oo < a r� I C J 1 I I 1 16a 1.1 4.8 THE APPLICANT IS AWARE THAT THE CURRENT PLAN DOES NOT MEET II z LO Q Q i3 ( �I �I / J ( REGULATORY FLOODPLAIN REQUIREMENTS AS PROPOSED AND IS CONTINUING \ / \ \ ✓ r 3.39% - -- - ` `'\ ` ` - 17a 1.5 6.7 THROUGH THE PLANNING PROCESS AT THE APPLICANTS OWN RISK. �� \ BUILDING AND CONSTRUCTION PERMITS FOR STRUCTURES NOT MEETING / ( • . _ I _/ \ r 18a 1.2 5.4 FLOODPLAIN REQUIREMENTS WILL BE HELD UP IF THE LOMR IS NOT w w m >- m m REGULATORY. < w P �, - - - - � 19a 0.5 2.6 Q Q w o 0 o o _ / 1 \ THE INTERIM POND OUTFALL IS PRIVATE AND WILL REQUIRE AN EASEMENT v v � w z w o° ,2 x 2.01%. \ ` \ I / C \ 1b 1.5 6.7 FROM ADJACENT PROPERTY OWNERS. o z Q v /�✓ 2 0 - ✓ - w 47[ \ I` _ J 1c 0.5 2.1 = o o v II 4. ,I - I \ �O vG `S>>S \ 1d 0.5 2.2 5 / 1 V \ •--- i 1e 12.3 69.4 511 2a 3.9 17.8 2b 0.5 3.1 5117 � _� 1 ( 2c 0.3 1.4 2d 0.8 3.6 w �' II - 1 n II 0 r5118 �� , ) 2e 3.3 15.1 Q z I I 1 / 1 3a 3.3 15.1 Q I I 1 �- J -I 3d 1.1 4.8 _j a_ II 11 I I II ' S1 3e 0.02 1.5 II II I I 5118 III 4a 2.8 13.2 r LJ J II II 4d 0.8 3.6 0 L I L J I I 5a 0.7 3.4 80 40 0 80 160 < z II 5d 0.4 2.3 (� - Know what's below. Q 6a 5.2 23.5 ORIGINAL SCALE: 1" = 80' J � I I _ ' 6d 0.4 1.8 Call before you dig. 0 0 � 7a 1.1 5.1CL - - - - - - - - - _-- = W EL/ZABETH ST = - _ _ - -- - - - - - 7d 0.2 1.1 ENGINEER'S STATEMENT - - - 8d 0.6 3.0 ENG NEERI JR = pG��L�Oi]� ILaG�� 9.1A 0.4 1.6 9.2a 3.3 14.2 [N]O LJ [F O LJ 1 3399 ; JOSEPH MA v �J���Ol O ° � DATA•° � SHEET 34 of 80 COLORADO P.E. S•°°••°°E�� FOR AND ON BEHALF OF JR ENGINEERING, LLC /ONAL JOB No. 39797.01 � I I NOTES: V) z SITE IS GREATER THAN 20 ACRES. N w W O i~- QQ wz � � - ` \ 10. I - - - THE RATIONAL METHOD HAS BEEN USED TO e e w N = w z SIZE INDIVIDUAL STORM PIPES AND DRAINS. e ~ LU W w z _ W s'�o l� I I REFER TO SWMM MAPS PROVIDED IN ORCHARD PL ~ z m W � _ = m U 17W11'1 h APPENDIX E OF THE DRAINAGE REPORT FOR v Q o Q ~ Q ADDITIONAL INFORMATION ON INFLOWS IN AND 1 � o W w W p N OUT OF SITE AND INFORMATION REGARDING J W O O cU O L` O OS1 OFFSITE BASINS AND HISTORIC BASINS. cn 0' of z o' >- - _ FW WMWMJ (nH M Z = ma- 0CLZW �/ I 0.6„5% / � � � LOCUST GROI/E Iw voi � i � � aQQQooQ THIRD FlL ING I ° I I o z � 7Q I I�i� �nG ►� NOTES � E Oy III I I p PLUM ST O N III THIS PROPERTY IS LOCATED WITHIN A CITY REGULATED 100-YEAR CANAL Z / 5120 , ` I I I IMPORTATION FLOODPLAIN AND FLOODWAY AND MUST COMPLY WITH c II I II r I 0S2 I CD CHAPTER 10 OF THE CITY MUNICIPAL CODE. �/ Uj N 00 CO 1 RESIDENTIAL USES IN THE 100-YEAR FLOODPLAIN MUST BE ELEVATED I O z 00 O � �- - _ _ _ _ _ _ _ - - _ IIII �I 0.09 51% ABOVE THE REGULATORY FLOOD PROTECTION ELEVATION. RESIDENTIAL USES I� W X - - - -F - - - -FO- - - - _ - - �p=_ _ _—— - - - - - III ARE PROHIBITED WITHIN THE FLOODWAY. 0 � O I I I I I I� I A FLOODPLAIN USE PERMIT IS REQUIRED FOR ANY WORK WITHIN THE Ld Q N (/� I I 100-YEAR FLOODPLAIN. A NO-RISE CERTIFICATION IS REQUIRED FOR ANY [r F I ELIZABETH ST Q C� X z I I I III III I I WORK WITHIN THE FLOODWAY. O J I I W I 1 ICI CRITICAL FACILITIES ARE PROHIBITED WITHIN THE 100-YEAR FLOODPLAIN. w m J 1 > 5115- - III I • THE APPLICANT IS AWARE THAT THE CURRENT PLAN DOES NOT MEET < O 00 00 CD �2 - 1 I I REGULATORY FLOODPLAIN REQUIREMENTS AS PROPOSED AND IS CONTINUING KEY MAP 0 CL 00 G 1 _- II Z THROUGH THE PLANNING PROCESS AT THE APPLICANT'S OWN RISK. SCALE: NTS W � X 1 I � 1 .2441% i 1 /;- - - -- O=F ` i I II J IIII BUILDING AND CONSTRUCTION PERMITS FOR STRUCTURES NOT MEETING O O FLOODPLAIN REQUIREMENTS WILL BE HELD UP IF THE LOMR IS NOT II 1 "1 I I I -- II III REGULATORY. 0- Li- ce I 111 IIII THE INTERIM POND OUTFALL IS PRIVATE AND WILL REQUIRE AN EASEMENT I I I �\ I IIII III O FROM ADJACENT PROPERTY OWNERS. Li II __ - - - - J U E 1° I11 LEGEND - - - - - - — _ _ _ O 5115 -�— - - - - � 6100 EXISTING MAJOR CONTOUR — 5117� - - - I\, EXISTING INTERMEDIATE CONTOUR rn - W - - - — - - - - - - - - - - - - 4 - - - S - - - - - - - - - S — - - S - - - ,S - - - — `; — �- 1e �10� PROPOSED MAJOR CONTOUR � S - - - - - 5 - - L - - - - - - W. ORCHARD PL 1.70% -� S __ - S - - - - - S - - - - _ PROPOSED INTERMEDIATE CONTOUR Q _ � � ---- -- I - -A ` I -�--�- �1 w ORCHARD PL ��._���_� � EXISTING STORM SEWER/RCP � - -� --�-- 5109.0( E _ o �, - - - . --'� ------' T 2e - - _ 3e PROPOSED STORM SEWER/RCP � o -� - -- _ - - - - - - - - - - - - - - 0 - - - - - Xs - - �— ° -5109.40 a • I o X _ - - - - - - - - - - - - - - E - - - F � � . . . PROPOSED SWALE 0 M i - - - - _ 3 E2 0) / - } - - - - - - - - - - - - -- -- - - 0"�5110 - - - - A BASIN ID o' c� , / 0.54 54% — — a�i rn r >t,� 1 /, - A: BASIN DESIGNATION z�A _ �1 I I B C B: AREA (AC) C: % IMPERVIOUS o 75 0001 NONE N INEE INNE INNE INEE INEE INEE immm immm ma Imm • I i OVERFLOW SWALE 1 ( ��� I I -m7�4 mm� c DRAINAGE DISCHARGE a U 1/ I z 1 i I O I DESIGN POINT Or OOYR 1 / 1 loo I � O c 1 � o o 0 �� PROPOSED FLOW DIRECTION N I I �i a I PROPOSED 100 YEAR FLOODWAY / 0 -� ° I \ - - - - - 10 I BASIN DRAINAGE AREA - - - - - - IJ - - -- _- - - - - TRACT A, I 5110 F1 ° I I # POND < THE SECOND REPLA T OF I 5110 11 I 1 ' SCENIC VIEWS, P.U.D. v� I�' I — 3.92 31% REC. NO. 98027263 I 149 = I 10 ° SCE/\�lC VIEWS POND ` 1.6 5110.98 �OYIR J \ r - I �r .'..•.�... .-.•,• ..• / ` FOREBAY / ENERGY _ - I / o \� DISSIPATION STRUCTURE 1J PROPOSED 100 YEAR FLOODPLAIN I _ \ if y' 5110.81 .510 I I ►n 'n 1 1 I S I EMERGENCY OVERFLOW / - F/ \ 1.02 16% 2 36.8 FT SPILLWAY— 0 LD �-f FL N9' �- - - \\\ ` \ as 4 a7 I / ELEVATION 5107.79 - - -5105 1 I-I ° - - - - - - - I ° \\ I I 511 p I 1 EFFECTIVE FLOODWAY BOUNDARYvv I i _ 5105 - 5105- 1 8.31% �' I /F <� I I \ 19 f FL HEADWALL y - \F S110 I �\ - - - / o� I /FLD DRAINAGE CHANNEL l \ I I �► - / / �� / ') 14140 z WATER QUALITY PROVIDED \ \ I �,y o - O G E I 0.33 ACRE-FT I I \ U) 100 YEAR VOLUME PROVIDED 9.57 ACRE FT � 1 \ ,�4 I r o I > II I _ Em NEW ME MENT I MEN ME MEN EliI 100 YR-WSELV 5108.89 I I \ I 1 0 Ld INEE NINEI I I III III EM \ I I r I I / / 100 YEAR VOLUME REQUIRED 1 I 1 y \ I r , I 4.88 ACRE-FT \ p \ i � � 1 0 • III I I \ 1 \ TOTAL RELEASE RATE 100 YEAR EVENT: 174 CFS q z I L \ F \ I / 1.82% - 2a -- Bl / \ ` T - - - - - - EFFECTIVE 100 YEAR FLOODPLAIN i '�`2 � \ ` FLO w w m m J m -O 1 0.58 0% _ 01 \ \ -sue, n L - HOKU LANE \ MELE LANE - � ��.>ooy� I 1 car < o z o — — \ Q Z Y Q U _. W lb LLJ ,� \ \ \ \ W U O \ � , mmmimm \ MEIN I IINEE \ I � I I I °5 I 1110101010'� M I 2.1 , I Ina � o \ \ \ -\ 1 o \ \ \ r \ \ � 2b ILL] I I 24) \1.03% \ I , I J J I a_ I D > ` I 40 20 0 40 80 \\ �° i _ _ — _ — — Know what's below. CD 4a �'� ORIGINAL SCALE: 1" = 4.0' \ Call before you dig. \ I l \ \ 0 \ s I \ I Y 9 Q Q W Q V � v ..0 I n I II y i J !G� v 1 I I II --- O 0 \ \ 1 A4 ' 62 I wCL \ \ \ I 1.23 5% ` �s� - - - 4. ENGINEER'S STATEMENT N 1 / �� \ F` �, I I ► -- - m I PREPARED o o I ¢. .,d I I ENGINEERI L� ��L��l1VIJ�LIVL�=�\� 2c r-)) E 3399 : *° JOSEPH MA O LJ\"J O lJ�l °° SHEET 35 OF 80 . DATA•�� COLORADO P.E. S E� SEE SHEET 36 FOR AND ON BEHALF OF JR ENGINEERING, LLC 10NA� JOB No. 39797.01 SEE SHEET 35 � W LLJ \ \ r J3 I o,D S \ 5110 �r- /~ / Q Q Wwz � � � I 1 �K �.1•� _ I ( J I I Wtn � wz � o_ _� U o' Ww � z 1 ) \ ?.�) N1.03% / / 1 c i { ` j// // ORCHARD PL ~ Z m Lj 0, m 0 0wo_ � N � - - / I WooUo zo 0.78 5% ° � ' l I v \ v ^�°�° ` �� I I ` __I_ I � � I � WWWWM _j I � — ins z = o_ o_ Uo_ zW � O D8 o � � aQaaooa 1 z a I y w _ \ \ 1 A 'A r / / f7 \ O PLUM ST U N �G� \ ' B2 c I ? LC) CD A4 \ \ � \\ \ s 114 00 CO % - - - - \) z 00 Ln I I I O � OC� IC4I. A. A i� I -- - I I LL WU � ELIZAaEr�sT �lot LIJ � x z I I Q O � I I LL m I 57° _ 11 W Q 000 KEY MAP � V) � 00 SCALE: NTS W � 4 l I� I ` I C2 II 0 I O O \ I I H -�: �� v LEGEND V i 0.42 7% �� / 18 D6 L 6g � 6100 EXISTING MAJOR CONTOUR \\ \ \ y 9g� I o - - - - - - - I \�\ ° ' �► \ \ \ ° EXISTING INTERMEDIATE CONTOUR 93 i, W PL UM ST \ \ \ \\ W. PLUM STm- �� ��� II o G o- - - - - S fi10� PROPOSED MAJOR CONTOUR D5 I i PROPOSED INTERMEDIATE CONTOUR .� OO EXISTING STORM SEWER/RCP - \� A8 / ' �/ _ _ _ 5>>5 - - T -- H P - • PROPOSED STORM SEWER/RCP C o -" � 4. � \ � . . . � U ' A9. I \ _ 1 PROPOSED SWALE O • BASIN ID cu A: BASIN DESIGNATION I / / V A �\\�\\� V A V i I, sK •�I I I D4 � a) � o, B: AREA (AC) 0 I C: % IMPERVIOUS ¢ 0.1684 I O I J ' ,�� - �I I II I a 1 I 7 rn 75 b\ rn_ / og I I ^ / I DRAINAGE DISCHARGE _o N �! ��° _ / �, DESIGN POINT U 06 aD �1'98q 1 42%- �� PROPOSED FLOW DIRECTION BASIN DRAINAGE AREA 40 6 � f 0.16 0% - - - L18% POND W 2d ° m I m \ LOT 1 BLOCK 1 / I n 1 NOTES-.O S THE SECOND REPLA T OF SCENIC VIEWS, R U.D. , `"\\ \ � / 1 • / / ,I I I / I `5 " REC. NO. 98027263 \� \V�\\ \ \ X 2.81,° A13 I II ° �� \ ° I I � SITE IS GREATER THAN 20 ACRES. \N\ \ \ \ ' 0.40 61% Al 1 I - n I«d \ / \ o -� \ THE RATIONAL METHOD HAS BEEN USED TO �� D2 SIZE INDIVIDUAL STORM PIPES AND DRAINS. \ 2.3�. / REFER TO SWMM MAPS PROVIDED IN \ ; \ \ \ \ / /Oj II APPENDIX E OF THE DRAINAGE REPORT FOR \ `^ I \ \ M\ �\ + , 3 I /�/ \ I I \ ADDITIONAL INFORMATION ON INFLOWS IN AND �/ \ , \ I OUT OF SITE AND INFORMATION REGARDING \ \ \ \\ \ \�\ \\ \ ' ■ A18 _ 3 39% 16 11d OFFSITE BASINS AND HISTORIC BASINS. 15115 0.72 7% - D--- \\ 2.64% �° _ °� n II MOUNTA/RE SUSDI VISION D1 \ BOOK M, PAGE 54 A14 NOTES � N \ I I J ) THIS PROPERTY IS LOCATED WITHIN A CITY REGULATED 100-YEAR CANAL IMPORTATION FLOODPLAIN AND FLOODWAY AND MUST COMPLY WITH � CHAPTER 10 OF THE CITY MUNICIPAL CODE. \ \ A16 I - - \ RESIDENTIAL USES IN THE 100-YEAR FLOODPLAIN MUST BE ELEVATED W 1\ \ �\ \\ \\ 4 0.12 6% 2.01% I -_- \ ABOVE THE REGULATORY FLOOD PROTECTION ELEVATION. RESIDENTIAL USES I \ \ \ �� A15 - o �_ I -- - - /' \ \ \ ARE PROHIBITED WITHIN THE FLOODWAY. o `v \ \ �' A FLOODPLAIN USE PERMIT IS REQUIRED FOR ANY WORK WITHIN THE z \ - _ _ 100-YEAR FLOODPLAIN. A NO-RISE CERTIFICATION IS REQUIRED FOR ANY WORK WITHIN THE FLOODWAY. N �I _ - - CRITICAL FACILITIES ARE PROHIBITED WITHIN THE 100-YEAR FLOODPLAIN. U A19 _ ` ` J �` �S \ -' THE APPLICANT IS AWARE THAT THE CURRENT PLAN DOES NOT MEET \ LO n- � TROY OCHELTREE & SONNY - __ REGULATORY FLOODPLAIN REQUIREMENTS AS PROPOSED AND IS CONTINUING II Z N Q Q I 0.35 2% OCHEL TREE 6' / \� J /( �/ \ s I THROUGH THE PLANNING PROCESS AT THE APPLICANTS OWN RISK. \ l QUIT CLAIM DEED �- - v \ �5115 F 1 / I BUILDING AND CONSTRUCTION PERMITS FOR STRUCTURES NOT MEETING REC. NO. 20210059013 - I -� -�_ - \ , / FLOODPLAIN REQUIREMENTS WILL BE HELD UP IF THE LOMR IS NOT >- JI_ - - - ���- \ _ REGULATORY. W W m m m h/ J J \ �� \ \ T \ 1� � � L THE INTERIM POND OUTFACE IS PRIVATE AND WILL REQUIRE AN EASEMENT Q Q z o FROM ADJACENT PROPERTY OWNERS. U U Q z y AARON STERN/ N. \ - _ _ _ - I I I U7 0' W ✓055a YN FAM/L Y TRUST C�� �l\ ��� \ - - _ ` _ W o = QUIT CLAIM DEED RE-C. NO. 202001101925117 OD- - \�� ` t✓ _ _ - i r- ��� � — s118 1 \ ✓ARED ROSS \\ N \ 0 �I / I W WARRANTY DEED \\\ \ \\ \\ \ \ I I \ (� Z REc. No. 20210070204 III — Q Q I 1 ��c I \ 1 �';r1 \\ I\ � �J I � , I � J 1 � �� _ I � Ix , J i \ W Q I , z,�\ I \ I 1 / 40 20 0 40 80 ~ Z I I r I \ / W. () Q 1 / r I J I J I l� // I -�) I, I 1 G E rl I (� / ORIGINAL SCALE: 1" = 40' Know what's below. w � —I r� I \I I Call before you dig. p o I �� J \` J CIL- ENGINEER'S STATEMENT PREPARED n� n nn �(� � � •�FPI�� JR 77- ENGINEERI L� LIED 11V11 L1VLr=� 0_) L1 ••a I\ O 7r IF(aW 3399 JOSEPH MA O (0DATA•' �� SHEET 36 OF 80 COLORADO P.E. S �� FOR AND ON BEHALF OF JR ENGINEERING, LLC /ONA� JOB N0. 39797.01 LLJ Ld wLj S w = » /1 O ORCHARDPL � �z � w � =� wmo m Lu /i�����,%�i� u. , I I c lz ool" 2 3 woo � oo 0 Q WwwwJE mm � mzwCal _ =�z uu o p cj� I ` �Am Imm J - Lu O PLUMST U N CD Tn _ __ _ _ --__ 36" FUTURE RCP — — - - - S — I - - S - -W. ORCHARD PL S — 'o --_ - ----�----` �— S —(s} —� S \C= - - S�—©� ��\ — i I z pNp 00 16e' 'o, A LLJ 2R- I - - - - - - -_ - - -� oQo 1 _\ EL IZABETHST�4/ _ - 1 3 4 m � OX 000 O2 \ � a_3 KEY MAP m — CD o04 o-OUTLOT 6 7 8/ � g SCALE: NTS w � _jIIrl TRACT A ITEECOND REPEAT OF LEGEND OHS�I ACCESS ROADL / c SCENIC VIEWS, PUD. —C NO 98027263 10R 100 YEAR WSELV CONDOMINIUM ASSOCIAT/ON 1— o ACCESS ROAD 1 SADDLE RIDGE COMMONS 6100 EXISTING MAJOR CONTOUR QUIT CLAIM DEED 5105 °O r EXISTING INTERMEDIATE CONTOUR 2002007515 I� II I I I � H o� Y ° o� I 30 RCP \� (\ I I I `" " " - Q 5100 o ° FUTURE OUTFALL i — 1 q ` L �100 PROPOSED MAJOR CONTOUR N (_ uj oo / ° LOCATION I rn TRACT A. 1:. o o INVERT 5098 \ / PROPOSED INTERMEDIATE CONTOUR 5100 I - - ' 8 0 EXISTING STORM SEWER RCP ,�. S � PROPOSED STORM SEWER/RCP Q �\\ y \\ \ ����\� -I I I I - ,a• �T - PROPOSED SWALE a SCEN/C VIEWS POND � I I \ o , � - - - ,v \\I � c o \ � � I � I I � � ,n \ � \ / � � PROPOSED FLOW DIRECTION � U \ \ �� �\ �`Y I I I - -- - - - , \ ELEVATION36.8 FT P5107A79 �`\ I // X \ 1 \II I BASIN DRAINAGE AREA �' M • 1 I \ \ \ \\ v\ / \ \\ \\ \ \ \ I10 111213 14 15 17 18I crE \ \ / I \ I ► � � r7l \ \ \ \ 1- I 3 5 6 7 8 \ \\\ \\ \\` �\ \ I I I I , „ \ 4 TRACT B - I / POND o v `' rn \ \ ! I I o i REGIONAL DETENTION / U — 175 PROVIDED VOLUME: 13.53 ACRE FT / V;\I \\ I /// I // \\ \✓ �\ \ \�\\� \�1L y /�/ - 1 + \ 100 YR WSEL 5107.18 �/ / / I DETENTION FROM THE JACOBS 1/2022 I / CONCEPTUAL DESIGN PLAN FOR THE I I ) l 1 \ I CANAL IMPORTATION BASIN 8.3 ACRE-FT j 1 ` 1 \ 1 4 I I I DETENTION REQUIRED FOR THE POLESTAR \ I 1 \ / \ \\ \ \ \ II g \ '1Q I 1, 11 12I 1I19 I II 21 22I1 i / / _ \ \ \ \ \ \ \ \ / I \ ONSITE IMPROVEMENTS 4.88 ACRE-FT 1 \ J w Q TOTAL REQUIRED VOLUME 13.18 ACRE-FT h ( \ o TRACT B I m TE � � 14� \ i -25 \\ I 33 I `,. 34 1_ I II J,/ \13 I , 8 I I I \ _ G TE \ -- 17 II III \ 26 t94 / _ 30 � _3_2s \ / �� AV ` vv � 35 i v 1 / v 11 w v '-/ A � ��23 v I I� 3 TR�4CT B 17 IN. \ - __ �� 1J V / V A \\ �g. W PLUM ST W PLUM ST o N Q 0 3 1 /I r v 1 I I II z00 Q a 00 38111 1 I 1 I J Ld m l,T / I o ' I �I / I l I / Q z z Y Iv � z > � w o z nT SLO D A T OF \\ I i \ \ \\ - J \ � Ec o. 9802 63 \ TRACT A g o ' E z �\\ 43 C\4 SCENICvws c TRACT A 1\ f ` - \ I— ? \ / \ \ \\�\ < \ 1 \ 44 \ I I I 1 1 J z z w \ / W 0 C O - - v� / C� LLJ Z w w�y,� X x—, — / cn Q 177- D III TI -,j SHEET OF _ �-�� 1 / Know what's below. �- 60 30 0 60 120 _ L —\ J7 T 1 W?&Y-OCHELTREE & \/ 1 \ I \ \ �\ / / / ` Iv/ \ / ORIGINAL SCALE: 1 = 60 Cal before you dig. JOB N0. 39797.01 24 APPENDIX G -LID EXHIBIT THIRD /LIN ( w I ` I I I h ( �\_ l I \- J I cn z Ql- � i / ° E �09 \ > ;, fll, \ 1 ` _ _ � / —� — '� I z Z - ``' w S920 1 / / _ � I 1 I I r�/ I / c \�\ 1 / w - Iww0o � \ � I( wZ � a � 0 � � � rf ,r.. 1 .09 ,x \ 1 \, l » � C ,L° � \ II I - / C� O \ \ r �; I 1 / I / \ ` l /1 - F- Z >- LLJ Cr-� wwwmz UNTREATED AREA / .� �o y / / o \ ORC'HARD PL — m P, x 1 I llI I \ \ %I M II 1 I1 / I\ / \\\ I ^ / 0 < 0 < -u, � oQ - / cn > ww > Q � rn 4 z ,X 5_ - 6 �. -�� 2 ,T �I ' ll \ / �- I l I J � � � z � > 00 2 3 / Z 1 i \ I/ / i \ I woo � o `` Zo > °I- 1� I` I \ _ �uI ,I \� z � zw � CJ O -' G -- ; _ � I --� �� -S i — _ 1� _ _ ' I / PLUMST U N _ _ Q / - - _ __ - - _ _ - - - - - - - - - - - - - s - - - - S - -W. ORCHARD PL s - - -1.70� i - - - —s�= `_ ._ S -- �- S -p - � S - - -s�—l � I Z oN 00 CO =``' --- W. ORCHARD PL 5109 3e \ J I O Wp oU � - - - - - — — E E / �/ ) p I - - _ — - _� - - - - - - - - - - - == =` w Q CN I I �-=-i -=1 - -� - - - - - - - - - - - - - - - - - - - - - - - - - / -,_ !�- � Ld Lu �T=T - .s 4x� DSO- - \ \ ELI�@EfIT Q J I I /' f — � J MEW OEM m ,- - r_ T _ I 1 2 3 4 OUTLOT A 5 6 -7' 8NORM I I~ / KEY MAP w C v � I I / � 9 E- 1�- l `\�� h i- I I � I SCALE: NTS � � I ITHE SECOND REPLA T OF \ I rn - I :^ — —C J \ O \ \ \ I I III r� I I � � I ' I\- ( ( I 1 � � o \ \ - \ -- I r�l I �� ,- SCENIC t//EWS- P.U.D. I�N - - - •} I t_ - -- - ' - e I ; LEGEND � r! __ - - - - - - - — — \ \ \ \ I I I I I rL I REC. NO. 98�17272 3 r I I a \� \� L I I^ y� la 3 I- I r I r- — — \� —6100 EXISTING MAJOR CONTOUR 1 \ \ D63E� ZL COMMONS I- + I 5110 � / f \ / CO OM/N/U ASSOC/4-T/ON -�`- I Q \\ A/M DEED 7 I 5110 I .92 ,z o o �� — — — — — — — EXISTING INTERMEDIATE CONTOUR REC. NO. 2002007515 RAIN GARDEN # 1 U) I OUTLOT \ \ \ \ 1 1A� ���� 1 I I I " ~.:.r .':: '.: _ IUJI < 5 05 I I \ i _ s100 PROPOSED MAJOR CONTOUR "r N \\� 1 1� '� I NAC A..: 1 0.Sp I \ / PROPOSED INTERMEDIATE CONTOUR rn 1 \�\ ` \�\\x \ SCENIC VEWS PON • .: I \ _ _ EXISTING STORM SEWER/RCP N 0.8 1 / \\\ \ \\��• \ I I I `' r I 23 _ • PROPOSED STORM SEWER/RCP 5110.00 I I — — = c�-� — - o {I ° — — — PROPOSED SWALE PROPOSED FLOW DIRECTION r� ca Q U �✓ o 0 \ \\S �� I -- - BASINDRAINAGEA A 0 • • \ \STORM ONTROL BOX -� I WATER QUALJTY PR VIDED \\ A RE / ` \\ ' �\ \\ \�► \ \\ h I I 3 10 11 12 13 14 15 17 18 0.33 35C 4 5� 65 75 A.8 I /�JC FiJ HJ HJ I�JC NJC 4 HJ AJC f I / 100 YEAR VOLUME PROVIDED 9.57 A E-FT 100 YR-WSELv 08.89 \ TRACT B 100 YEAR VOLUME R UIRED4.8 TOTAL RELEASE RATE 100 YEAR EVENT.A 4 CFS t^ 2 _ .ca -c / RAIN GARDEN 1 U — y C l _ RAIN GARDEN # 2 8 IRR PAP UNTREATED AREA \ RAIN GARDEN 2 2' / I1 3 _ \ _ 4 # RAIN GARDEN # 3 f I 9� 10 '11■ ■12 \ 19 i i 21 22 I I 5 / l \ RAIN GARDEN 3 � I I I I I f I � w _ 510 { # I v VA\ � , � � �7� a \� a 1 r� l\ RAIN GARDEN # 4 TRACT B � � `-►- � - I � 1 � - --\ -, \ / \\ TE10) \ \ RAIN GARDEN # 5 tK I - - \ I 4 FW2 I z FE2 I / � // \ � � / • � .� � '2cJ I } ( 33 I 34 i __, RAIN GARDEN # 6 I II � GTE 2944 - - ' AREAS TREATED IN DETENTION POND FOR WQ T �� �\ \v 19 o vv 32 I __ � - 1 � TRACT B UNTREATED IMPERV AREA \ RAIN GARDEN # 4 p 1 i f I \ \ �, 4 a- o TRACT A �26; b° % W PLUM ST W PLUM ST Ld o 7 \ 1 ns v VAS E E E — � � — _ z � � � V\ / SCENIC V/EW,9� 7 — \�` UNTREATED AREA — LID/WQ TREATMENT T - 1 / o o y / 4 i 37 / I I ✓ / CINI Treatment Method Impervious Area Treated -SF Total Area-SF Percent Treated 0 X 0 i I I II r `` E RAIN GARDEN #1 2131418 II N Q Q Gi" 40 0 / I s j �' RAIN GARDEN #2 37,445 0\0 RAIN GARDEN #3 21,579 .23 / ,��,� 38 � I ° I I 323,501 83.8% m m RAIN GARDEN #4 15,160 J J m ° - I TRA I RAIN GARDEN #5 15,160 Q Q Ld o Z o \ ° �� 8q I I RAIN GARDEN # 5 U) U) o Y RAIN GARDEN #6 20,739 1 1 Q U / i \ \ � / \` Al I WQ- Detention Pond 60,907 60,907 15.8% _ > w Q = Imo\ \\ I 1 \ \ `� ° 43 0% — — Untreated Area 1455 1455 0.4% v OF ? - , V \ t3` H.P 511,Z� � \ -- r O 42o E / NOTE: OFFSITE IMPERVIOUS AREA ASSOCIATED WITH LOCUST GROVE IS NOT � -� Ec o. s8o2 s3 TRACT A � za TRACT C . • . �• / INCLUDED IN THIS AREA. THAT AREA IS TREATED IN THE DETENTION POND. LLj `\ I 43 0 \ �: �► TRACT A r ° I C SCENIC KEWS c \� z � o� 36 ze I I 1 Q .8 , z 3 Al % \ 'oe ' n���° o _ RAIN GARDEN # 6 / �r� I \ W Q z 4R \ 44 I C� \ I ' �' nor — — xf — — 45 x 35 40 5113) Ar Z I v Q LI 9T J � 1 3 as _ U) Q 48 12.J1%, _ 1 ^ 5120.47 ;z Q \ - - (777 Fl- I r- 5 60 30 0 60 120 Know what's below. SHEET 1 OF 1 l I _ / r \ _ \ \ ` �� �� I\\ � - _ _ � � �\ I � 1\ \ o� � `�==,..1- — /RRs /P or ~> � \ � � � 1 , � -1�� � � \\ �� CIF7-A- y.. __.._. ___ _ _ , . RR G I I / _ Call before you dig. JOB NO. 3979701 ORIGINAL SCALE: 1 - 60