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HomeMy WebLinkAboutMOUNTAIN'S EDGE - FDP - FDP180006 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTFINAL DRAINAGE AND EROSION CONTROL REPORT February 20, 2018 Mountain’s Edge Fort Collins, Colorado Prepared for: Lorson South Land Corp Jeff Mark 212 N. Wahsatch Avenue, Suite 301 Colorado Springs, CO 80903 719-635-3200 Prepared by: 301 N. Howes Street, Suite 100 Fort Collins, Colorado 80521 Phone: 970.221.4158 www.northernengineering.com Project Number: 911-007  This Drainage Report is consciously provided as a PDF. Please consider the environment before printing this document in its entirety. When a hard copy is absolutely necessary, we recommend double-sided printing. RE: Final Drainage and Erosion Control Report for Mountain’s Edge Dear Staff: Northern Engineering is pleased to submit this Final Drainage and Erosion Control Report for your review. This report accompanies Final Development Plan submittal for the proposed Mountain’s Edge development. This report has been prepared in accordance to Fort Collins Stormwater Criteria Manual (FCSCM), and serves to document the stormwater impacts associated with the proposed project. We understand that review by the City is to assure general compliance with standardized criteria contained in the FCSCM. If you should have any questions as you review this report, please feel free to contact us. Sincerely, NORTHERN ENGINEERING SERVICES, INC. Stephanie Thomas, PE Project Engineer Mountain’s Edge Final Drainage Report TABLE OF CONTENTS I. GENERAL LOCATION AND DESCRIPTION ................................................................... 1 A. Location ............................................................................................................................................. 1 B. Description of Property ..................................................................................................................... 1 C. Floodplain.......................................................................................................................................... 3 II. DRAINAGE BASINS AND SUB-BASINS ....................................................................... 4 A. Major Basin Description .................................................................................................................... 4 B. Sub-Basin Description ....................................................................................................................... 4 III. DRAINAGE DESIGN CRITERIA ................................................................................... 5 A. Regulations........................................................................................................................................ 5 B. Four Step Process .............................................................................................................................. 5 C. Development Criteria Reference and Constraints ............................................................................ 6 D. Hydrological Criteria ......................................................................................................................... 6 E. Hydraulic Criteria .............................................................................................................................. 6 F. Floodplain Regulations Compliance .................................................................................................. 7 G. Modifications of Criteria ................................................................................................................... 7 IV. DRAINAGE FACILITY DESIGN .................................................................................... 7 A. General Concept ............................................................................................................................... 7 B. Water Quality Treatment ................................................................................................................ 13 C. SWMM Modeling ............................................................................................................................ 13 D. Overtopping Analysis for Storm Line 10 ......................................................................................... 14 E. Specific Details ................................................................................................................................ 15 V. CONCLUSIONS ...................................................................................................... 15 A. Compliance with Standards ............................................................................................................ 15 B. Drainage Concept ............................................................................................................................ 15 References ....................................................................................................................... 16 Mountain’s Edge Final Drainage Report APPENDICES: APPENDIX A – Hydrologic Computations APPENDIX B – Hydraulic Computations B.1 – Detention Ponds B.2 – Water Quality B.3 – Storm Sewers B.4 – Inlets B.5 – Overtopping Analysis B.6 – Overflow Weirs B.7 – Erosion Control Mats Calculations APPENDIX C – Erosion Control Report APPENDIX D – LID Exhibit APPENDIX E - SWMM Modeling APPENDIX F – References LIST OF FIGURES: Figure 1 – Aerial Photograph ................................................................................................ 2 Figure 2– Proposed Site Plan ................................................................................................ 3 Figure 3 – Existing Floodplains ............................................................................................. 4 LIST OF TABLES: Table 1 - Historic Rational Basin Summary ............................................................................ 8 Table 2 - Proposed Rational Basin Summary ........................................................................ 10 Table 3 - Detention Pond Summary ..................................................................................... 11 Table 4 - Historic Stormwater Release and Allowable Developed Release ................................. 12 Table 5 - Proposed Stormwater Release ............................................................................... 12 MAP POCKET: HDR1 – Historic Drainage Exhibit DR1 - Drainage Exhibit Mountain’s Edge Final Drainage Report 1 I. GENERAL LOCATION AND DESCRIPTION A. Location 1. Vicinity Map 2. A tract located in the southwest quarter of Section 21, Township 7 North, Range 69 West of the 6th Prime Meridian, City of Fort Collins, County of Larimer, State of Colorado. 3. Bounded to the north by private property, to the west by Overland Trail, to the east by the Brown Farm Subdivision, and to the south by Drake Road. 4. Significant offsite flows are directed into the site through Dixon Creek. Dixon Creek traverses the Mountain’s Edge site within the southern half. Additionally, two existing culverts cross Overland Trail. These culverts convey stormwater runoff from the property to the west. These off-site flows will be conveyed safely to ultimate outfall locations within the Mountain’s Edge site. 5. The Mountain’s Edge property has not been studied with the previous proposals or drainage studies. B. Description of Property 1. The site is approximately 19.67 acres. This acreage includes a portion of the adjacent Overland Trail Right of Way. Mountain’s Edge Final Drainage Report 2 Figure 1 – Aerial Photograph 2. The existing site is generally comprised of vacant land with natural grasses and vegetation. A house, gravel drive, and out-structures exist on the site. Off-site basins include portions of adjacent Overland Trail. 3. Approximately 14.7 acres of off-site basin, west of Overland Trail, drains through the Mountain’s Edge site to the historic discharge location in the northeast corner of the site. Approximately 63.6 acres of off-site basin, west of Overland Trail, drains through the site within the Dixon Creek channel. 4. The north half of the site is within the Canal Importation Basin. The northern 1/3 of the site slopes to the northern property line. A portion of the center of the site slopes to the east and overland flows across the existing single-family lots. The southern half of the site is located within the Spring Creek Basin and slopes south to the Dixon Creek drainage channel. 5. A report by Soilogic dated June 11, 2015 lists the soils for the area as consisting of silty/clayey sand, gravel, cobble and sandy lean clay ranging from 9 to 15 feet below the ground surface. A Web Soil Survey by the Natural Resources Conservation Service indicates soils are classified as Hydrologic Soil Group B and have a moderate infiltration rate. For this study, the soils were modeled as a Soil Group C with a slow infiltration rate to account for the soil variations within the soil borings. 6. The proposed project site plan is composed of 20 townhome buildings, 14 single-family lots, public local streets, sidewalk, private asphalt drives, and detention ponds. Mountain’s Edge Final Drainage Report 3 7. This site will employ water quality features and runoff reduction facilities including rain gardens, minimization of directed connected areas of imperviousness, and extended detention basins. Figure 2– Proposed Site Plan 8. No existing irrigation facilities are known at this time. 9. The project site has not been a part of any known previous drainage study. C. Floodplain The subject property is not located in a FEMA or City regulatory floodplain. Mountain’s Edge Final Drainage Report 4 Figure 3 – Existing Floodplains II. DRAINAGE BASINS AND SUB-BASINS A. Major Basin Description 1. The Mountain’s Edge project is located within two major drainage basins. The northern half of the site is located within the Canal Importation Basin. The southern half of the site is located within the Spring Creek Basin. B. Sub-Basin Description 1. Historically, the stormwater runoff and off-site flows within the northern half of the site generally flow in two directions. Stormwater runoff in the northern 1/3 of the site generally flows to the northern boundary and is collected within a swale along the access roadway on the adjacent property. Flows are conveyed to a channel in the Brown Farm 3rd Subdivision. Stormwater within the remainder of the northern half of the site overland flows across the existing single-family lots along the eastern boundary of the site. 2. Historically, stormwater runoff within the southern half of the site overland flows to the Dixon Creek channel. Once collected in the channel it is conveyed under Drake Road and ultimately outfalling to Spring Creek. 3. The proposed plan will generally detain developed flows and release to the Dixon Mountain’s Edge Final Drainage Report 5 Creek (Spring Creek Basin) at the historical flow rates. III. DRAINAGE DESIGN CRITERIA A. Regulations There are no optional provisions outside of the FCSCM proposed with the Mountain’s Edge project. B. Four Step Process The overall stormwater management strategy employed with the Mountain’s Edge project utilizes the “Four Step Process” to minimize adverse impacts of urbanization on receiving waters. The following is a description of how the proposed development has incorporated each step. Step 1 – Employ Runoff Reduction Practices Several techniques have been utilized with the proposed development to facilitate the reduction of runoff peaks, volumes, and pollutant loads as the site is developed from the current use by implementing multiple Low Impact Development (LID) strategies including: Preserving natural areas south of the Dixon Creek. Minimizing site disturbance. Proposed smaller private streets will allow for greater open space in the center of the site. This approach allows for a lower percent imperviousness. Providing vegetated open areas throughout the site to reduce the overall impervious area and to minimize directly connected impervious areas (MDCIA). Routing flows, to the extent feasible, through rain gardens to provide additional infiltration. Providing on-site detention to increase time of concentration, promote infiltration and reduce loads on existing storm infrastructure. Step 2 – Implement BMPs That Provide a Water Quality Capture Volume (WQCV) with Slow Release The efforts taken in Step 1 will facilitate the reduction of runoff; however, this development will still generate stormwater runoff that will require additional BMPs and water quality. A majority of stormwater runoff from the site will ultimately be intercepted and treated in proposed rain gardens and extended detention basins. Water quality for areas not routed through the rain gardens will be provided within the extended detention basin volume. Step 3 – Stabilize Drainageways This property discharges detained stormwater to an existing drainage channel (Dixon Creek). The proposed release from this property is expected to require erosion control mats to stabilize the drainage way at the proposed pipe outfalls. Additionally, any proposed 4:1 grading will be required to be stabilized with erosion control blankets along the Dixon Creek. The majority of the Dixon Creek channel will remain undisturbed. Step 4 – Implement Site Specific and Other Source Control BMPs. The proposed project will improve upon site specific source controls compared to historic conditions: Trash receptacles within home will allow for the disposal of solid waste. Rain Gardens and extended detention basins to provide for water treatment prior to flows being released to existing drainageways and storm infrastructure. Mountain’s Edge Final Drainage Report 6 Standard Operating Procedures (SOPs) for BMP maintenance of Rain Gardens, Detention ponds, and associated drainage infrastructure to remove sediment accumulation regularly. C. Development Criteria Reference and Constraints 1. The proposed site is a part of the Spring Creek and Canal Importation Drainage Basins. These basins requires a 2-year historic stormwater release from the developed property. 2. This site is subject to the LID requirements per the City of Fort Collins. Please see the LID Exhibit located in the Appendix for calculations concerning LID treatment. The site must either have the following: 75% of total new impervious areas must be treated through an LID (Low Impact Development) treatment BMP, or 50% of total new impervious areas must be treated through an LID (Low Impact Development) treatment BMP and 25% of new pavement shall be pervious. D. Hydrological Criteria 1. The City of Fort Collins Rainfall Intensity-Duration-Frequency Curves, as depicted in Figure RA-16 of the FCSCM, serve as the source for all hydrologic computations associated with the development. Tabulated data contained in Table RA-7 has been utilized for Rational Method runoff calculations. 2. The Rational Method has been employed to compute stormwater runoff utilizing coefficients contained in Tables RO-11 and RO-12 of the FCSCM. 3. EPA SWMM program was utilized for to determine detention storage calculations. 4. Three separate design storms have been utilized to address distinct drainage scenarios. The first event analyzed is the “Minor,” or “Initial” Storm, which has a 2- year recurrence interval. The second event considered is the “Major Storm,” which has a 100-year recurrence interval. The third storm computed, for comparison purposes only, is the 10-year event. 5. No other assumptions or calculation methods have been used with this development that are not referenced by current City of Fort Collins criteria. E. Hydraulic Criteria 1. As previously noted, the subject property historically drains to the north and south. 2. All drainage facilities proposed with the Mountain’s Edge project are designed in accordance with criteria outlined in the FCSCM and/or the Urban Drainage and Flood Control District’s (UDFCD) Urban Storm Drainage Criteria Manual. 3. As stated previously, the subject property is not located within a FEMA regulatory floodplain. 4. The Mountain’s Edge project does not propose to modify any natural drainageways. 5. The Mountain’s Edge project proposes to discharge developed stormwater runoff for the site to Dixon Creek at the historic 2-year rates. Mountain’s Edge Final Drainage Report 7 F. Floodplain Regulations Compliance 1. As previously mentioned, all structures are located outside of any FEMA 100-year floodplain, and thus are not subject to any floodplain regulations. G. Modifications of Criteria 1. The proposed development is not requesting any modifications to criteria at this time. IV. DRAINAGE FACILITY DESIGN A. General Concept 1. The main objectives of the Mountain’s Edge drainage design are to maintain the allowable storm runoffs as outlined within the Spring Creek Basin master plans. This project will divert all developed runoff to the historic discharge location for the Spring Creek Basin. The historic discharge location for the Canal Importation Basin will not be utilized for on-site developed stormwater release from this project. 2. Per the development guidelines, half of any existing adjacent roadway is required to be detained and treated on-site, as is feasible and reasonable. With this development, half of Overland Trail (north of Bluegrass) is proposed to be detained and treated within the Mountain’s Edge project. Overland Trail (south of Bluegrass) and Drake Road are adjacent to the site, but are not adjacent to the planned development. As such, detention and treatment of these areas will be significantly challenging. In order to meet this guideline, extensive storm infrastructure and disturbance of existing vegetation would be required. With this in mind, these areas of Overland Trail (south of Bluegrass) and Drake Road are not proposed to be detained and treated on the Mountain’s Edge site. 3. A list of tables and figures used within this report can be found in the Table of Contents at the front of the document. The tables and figures are located within the sections to which the content best applies. 4. Historic runoff from the Mountain’s Edge project site was evaluated. This evaluation provided the historic 2-yr and 100-yr peak runoff rates for the existing site and historic discharge locations. Basin HA Basin HA is generally the southern half of the property. Stormwater within this portion of the existing property generally flows via overland to Dixon Creek, from there it is conveyed to Spring Creek through existing drainage infrastructure. Basin HA is within the Spring Creek Basin. Basin HA was subdivided into 3 sub-basins to further aid in design. Basin HA1 contains the area of the site that will remain mostly undisturbed and pervious. This area includes Dixon Creek. Basin HA2 contains area north of Dixon Creek that will be developed with this project. Basin HA3 contains existing Overland Trail Right of Way proposed to be detained and treated with this project. Mountain’s Edge Final Drainage Report 8 Basin HB Basin HB is generally the northern half of the property. Stormwater within this portion of the existing property generally flows via overland the existing single-family development or to historic undefined swale adjacent the existing access road for the Holiday Twin Drive-In Theater, north of the property boundary. These stormwater flows are conveyed through existing drainage infrastructure to the detention ponds within the Brown Farm Subdivision. Basin HB is within the Canal Importation Basin. Basin HB was subdivided into 3 sub-basins to further aid in design. Basin HB1 contains the northern 1/3 of the property. This area generally drains to the northern property line and is collected in an undefined swale along the off-site access road to the Holiday Twin Drive-in Theater. From there, flows are conveyed to a City owned and maintained drainage easement through the Brown Farm Subdivision. Basin HB2 contains existing Overland Trail Right of Way proposed to be detained and treated with this project. Basin HB3 contains a portion of the property that generally flows via overland to the eastern boundary. Stormwater from this location historically flows through the adjacent single-family lots to Compass Court. Table 1 - Historic Rational Basin Summary DRAINAGE SUMMARY TABLE DESIGN POINT BASIN ID TOTAL AREA (acres) C2 C100 2-yr Tc (min) 100-yr Tc (min) Q2 (cfs) Q100 (cfs) 1 HA1 4.07 0.25 0.31 14.3 13.9 1.96 8.68 1 HA2 4.18 0.25 0.31 31.8 29.9 1.31 5.95 1 HA3 0.33 0.57 0.71 24.0 19.4 0.27 1.33 2 HB1 5.60 0.25 0.31 21.4 20.3 2.18 9.80 2 HB2 0.47 0.57 0.71 15.9 13.5 0.49 2.29 3 HB3 4.66 0.25 0.31 37.2 34.5 1.32 6.06 5. The Mountain’s Edge project divided the site into seven (7) major drainage basins, designated as Basins A, B, C, D, OS, HT and UD. The drainage patterns anticipated for each basin and sub-basin are further described below. Basin A Basin A consists of proposed single-family attached buildings, single-family lots, sidewalk, roadways, landscape areas and Detention Pond 1. Basin A is subdivided into 8 sub-basins (A1-A8). Runoff from Basins A1-A8 is detained in Detention Pond 1. Stormwater runoff within Basin A1 is treated for water quality and LID in Rain Garden 1. Stormwater runoff from Basins A2-A8 is treated for water quality within Detention Pond 1. The stormwater release from Detention Pond 1 will be routed south, through the site, to Dixon Creek. Mountain’s Edge Final Drainage Report 9 Basin B Basin B consists of proposed single-family attached buildings, single-family lots, sidewalk, roadways, landscape areas and Detention Pond 2. Basin B is subdivided into 7 sub-basins (B1-B7). Runoff from Basins B1-B7 is detained in Detention Pond 2. Stormwater runoff for Basins B1-B7 will be treated for water quality within Detention Pond 2. The stormwater release for Detention Pond 2 will be conveyed south, through the site, to Dixon Creek. Off-site stormwater from Basin OS1 will be conveyed through the project to the historic discharge location for the Canal Importation Basin through a proposed pipe. Basin C Basin C consists of proposed single-family attached buildings, sidewalk, roadways, landscape areas and Detention Pond 3. Basin C is subdivided into 2 sub-basins (C1- C2). Runoff from Basins C1-C2 is detained in Detention Pond 3. Stormwater runoff for Basins C1-C2 will be treated for water quality within Detention Pond 3. The stormwater release for Detention Pond 3 will be conveyed south to Dixon Creek. Basin D Basin D consists of proposed single-family attached buildings, single-family lots, sidewalk, roadways, landscape areas and Detention Pond 4. Basin D is subdivided into 6 sub-basins (D1-D6). Runoff from Basins D1-D6 is detained in Detention Pond 4. Stormwater runoff for Basins D1-D5 will be treated for water quality and LID within Rain Garden 2. Water quality treatment for Basin D6 is planned within Detention Pond 4. The stormwater release for Detention Pond 4 will be conveyed south to Dixon Creek. Basin UD Basin UD1 consists of proposed sidewalk and roadways. Runoff from Basin UD1 will not be detained. Stormwater runoff for Basin UD1 generally will be conveyed through existing roadways within the Brown Farm Subdivision. No LID treatment is planned for Basin UD1. Basin UD2 consists of open space and Dixon Creek. No detention is proposed for this basin as it is not being developed and generally will remain undisturbed. Minor grading is proposed within this basin. Basin HT1 Basin HT1 is an off-site basin that consists of the existing drive-in theater. Basin HT1 consists of mostly vegetated undeveloped land and gravel parking. HT1 generally gets conveyed in the small drainage swale on the northside of the Holiday Twin access road until it reaches the existing ticket booth. At the ticket booth, the flows overtop the existing access road into an undefined swale along the boundary of Holiday Twin and the Brown Farm Subdivision. This basin was included in order to document the undetained flow from the off-site basin. This flow may affect lots within the Brown Farm Subdivision. As this is an off-site condition, there are no improvements planned with this development. Basin OS Basin OS1 is an off-site basin west of Overland Trail. This basin stretches to west to Horsetooth Reservoir. Based on existing topography, this basin was determined to be approximately 14.7 acres. During a 100-year event, stormwater from this basin will Mountain’s Edge Final Drainage Report 10 be conveyed to a culvert passing under Overland Trail within Basin B1. A SWMM model was utilized to determine the maximum flow that would pass through the existing culvert during a 100-year event. The maximum flow was determined to be 16.2 cfs with ponding west of Overland Trail. This flow will be safely passed through Basin B to the historic undefined swale along the boundary of Holiday Twin and the Brown Farm Subdivision. Basin OS2 is an off-site basin west of Overland Trail. This basin stretches to west to the Dixon Creek Reservoir. This off-site basin contributes to Dixon Creek. Based on the Fort Collins SWMM model for the Spring Creek Basin, this basin was determined to be approximately 72.2 acres minus 8.58 acres of historic on-site basin, for a total 63.62 acres. During a 100-year event, stormwater from this basin will be conveyed to an existing 18” culvert passing under Overland Trail within Basin UD2. The full 100-year flow is restricted by the 18” culvert and stormwater will pool west of Overland Trail. At a depth of approximately 6 feet above the culvert invert, the water will bypass the culvert and continue south down a roadside swale on the west side of Overland Trail. A SWMM model was utilized to determine the maximum flow that would pass through the existing culvert during a 100-year event. The maximum flow was determined to be 22.0 cfs with 18.83 cfs continuing south along Overland Trail. Table 2 - Proposed Rational Basin Summary DRAINAGE SUMMARY TABLE DESIGN POINT BASIN ID TOTAL AREA (acres) C2 C100 2-yr Tc (min) 100-yr Tc (min) Q2 (cfs) Q100 (cfs) A1 A1 1.45 0.74 0.92 5.0 5.0 3.04 13.25 A2 A2 0.27 0.59 0.73 5.0 5.0 0.45 1.95 A3 A3 0.23 0.57 0.71 5.0 5.0 0.38 1.64 A4 A4 0.25 0.58 0.72 5.0 5.0 0.42 1.83 A5 A5 1.14 0.89 1.00 6.7 5.6 2.63 10.95 A6 A6 0.34 0.67 0.83 5.0 5.0 0.65 2.86 A7 A7 0.41 0.55 0.69 12.6 9.5 0.45 2.21 A8 A8 1.54 0.41 0.52 9.3 8.1 1.46 6.66 B1 B1 0.42 0.95 1.00 5.2 5.0 1.13 4.14 B2 B2 0.62 0.59 0.74 6.1 5.4 0.98 4.57 B3 B3 1.22 0.83 1.00 5.0 5.0 2.86 12.10 B4 B4 0.06 0.72 0.90 5.0 5.0 0.12 0.52 B5 B5 0.19 0.78 0.98 5.0 5.0 0.42 1.82 B6 B6 0.40 0.50 0.62 10.3 9.1 0.44 2.02 B7 B7 1.09 0.30 0.38 6.9 6.4 0.86 3.85 C1 C1 0.15 0.56 0.70 5.0 5.0 0.25 1.08 C2 C2 0.48 0.39 0.48 5.8 5.1 0.51 2.31 D1 D1 0.25 0.95 1.00 5.0 5.0 0.68 2.50 D2 D2 1.66 0.71 0.89 5.0 5.0 3.36 14.65 Mountain’s Edge Final Drainage Report 11 6. Four (4) detention ponds are proposed with the Mountain’s Edge development. These ponds will restrict all runoff from the developed site to historic 2-yr flowrate based on the master drainage plan for the Spring Creek Basin. Detention Pond 1 Detention Pond 1 detains developed runoff from Basin A. Detention Pond 1 has a total 3.50 feet of freeboard from the 100-yr WSEL to the lowest proposed top of foundation. Additionally, the emergency spill location is 1.1 feet below the lowest proposed top of foundation. Water Quality is proposed within the pond volume through an approved outlet structure. The pond release is routed to Dixon Creek. Detention Pond 2 Detention Pond 2 detains developed runoff from Basin B. All minimum opening elevations (MOEs) will need to be set at least 1 ft above the 100-yr WSEL. Water Quality is proposed within the pond volume through an approved outlet structure. Additionally, Pond 2 will be designed to convey emergency overflow through the outlet structure. The pond release is routed to Dixon Creek. Detention Pond 3 Detention Pond 3 detains developed runoff from Basin C. Detention Pond 3 has a total 2.96 feet of freeboard from the 100-yr WSEL to the lowest proposed top of foundation. The emergency spill for Pond 3 will be directed through the swale south of Building 18 to Pond 4. Water Quality is proposed within the pond volume through an approved outlet structure. The pond release is routed to Dixon Creek. Detention Pond 4 Detention Pond 4 detains developed runoff from Basin D. Detention Pond 4 has a total 3.3 feet of freeboard from the 100-yr WSEL to the lowest proposed top of foundation. The emergency spill for Pond 4 will be directed through an emergency spill weir. Water Quality is provided upstream of the detention pond within Rain Garden 2, and additional water quality is proposed within the pond volume through an approved outlet structure. The pond release is routed to Dixon Creek. Table 3 - Detention Pond Summary Detention Pond Summary | Proposed Condition Pond 100-yr Volume (ac-ft) 100-yr WSEL WQCV (ft3) WQCV WSEL Max Release (cfs) 1 1.42 5145.31 3,251 5141.80 0.35 2 1.04 5140.04 2,987 5137.87 0.40 3 0.14 5145.62 296 5143.01 0.10 4 1.03 5142.04 970 5136.45 1.40 Mountain’s Edge Final Drainage Report 12 Total Stormwater Release from Site The total allowable 100-yr release from the site was evaluated based on the historic Basins HA and HB. The allowable release for the Spring Creek Basin is a summation of the 100-yr historic runoff from Basin HA1 and the 2-yr historic runoff from Basins HA2 and HA3. The allowable release for the Canal Importation Basin is a summation of the 2-yr historic runoff from Basins HB1-HB3. Table 4 - Historic Stormwater Release and Allowable Developed Release Historic Stormwater Release Allowable Developed 100- yr Release (cfs) Pond/ Basin 2-yr Flow (cfs) 100-yr Flow (cfs) HA1 1.96 8.68 8.68 HA2 1.31 5.95 1.31 HA3 0.27 1.33 0.27 TOTAL BASIN HA 3.54 15.96 10.26 HB1 2.18 9.80 2.18 HB2 0.49 2.29 0.49 HB3 1.32 6.06 1.32 TOTAL BASIN HB 3.99 18.15 3.99 Based purely on a summation of detention pond releases and the basin runoff for Basin UD2, the total discharge from Mountain’s Edge to Dixon Creek would be 11.29 cfs. This is 1.03 cfs more than the allowable. Table 5 - Proposed Stormwater Release Proposed Stormwater Release Pond/ Basin 100-yr Flow (cfs) Basin HA Pond 1 0.35 Pond 2 0.40 Pond 3 0.10 Pond 4 1.40 Basin UD2 9.04 Total Basin HA 11.29 Basin HB UD1 0.52 Total Basin HB 0.52 Mountain’s Edge Final Drainage Report 13 The pond volumes and pond releases were maximized based on a combination of available storage volume within of the ponds and total release durations based on the Colorado Revised Statute 37-92-602(8). Due to the 1.03 cfs discrepancy, a SWMM model was utilized to measure the flow in Dixon Creek from this site. The SWMM model accounts for the varying times to peak for the discharges from the ponds and Basin UD2. This SWMM model shows a 100- year peak flow from the site of 10.10 cfs contributing to Dixon Creek. This meets the allowable discharge of 10.26 cfs. The proposed site will generally detain all developed flows from the property to the 2- year historic release for the Spring Creek Basin. Additionally, any undetained runoff from the site will comply with the 2-year historic release for the Canal Importation Basin. A full-size copy of the Drainage Exhibit can be found in the Map Pocket at the end of this report. B. Water Quality Treatment 1. A combination of 12-hr Rain Gardens and 40-hr Extended Detention Basins will provide water quality for the site, including a portion of the Overland Trail right of way. 2. Water Quality within the Detention Ponds will be provided through approved outlet structures. C. SWMM Modeling 1. A SWMM model was created to model multiple drainage concepts that are challenging to model using standard hydraulic and rational calculations. These concepts include the following: • Peak flow from Basin OS2 through the existing pipe under Overland Trail during a 100-yr event. The total flow that spills to the south and bypasses the Dixon Creek during a 100-yr event. ▪ During a 100-year event, total flow in the existing culvert is 22.0 cfs and 18.83 cfs bypasses the Dixon Creek continuing south along Overland Trail roadside swale. • Peak flow from Basin OS1 routed through Basin B and discharged at the boundary of Holiday Twin Drive-in and Brown Farm Subdivision during a 100-year event. ▪ During a 100-year event, 16.20 cfs is conveyed through the Mountain’s Edge development from Basin OS1. • Total emergency overflow rate for Basin B if the 100-yr orifice for Pond 2 is clogged. The outlet structure for Detention Pond 2 will be required to convey this flow to Dixon Creek prior to the pond overtopping. ▪ If the Detention Pond 2 100-year orifice were to become clogged during a 100-year event, the pond fill up and approximately 0.23 cfs would spill through the outlet structure and continue to Dixon Creek. Mountain’s Edge Final Drainage Report 14 • Total emergency overflow rate for Basin D if the 100-yr orifice for Pond 4 is clogged. The emergency overflow weir for Detention Pond 4 will be required to convey this flow to Dixon Creek prior to the pond overtopping. ▪ If the Detention Pond 4 100-year orifice were to become clogged during a 100-year event, the pond would fill up and approximately 0.08 cfs would spill through the overflow weir and continue to Dixon Creek. Even though this flow is minimal, an overflow weir with the capacity to discharge approximately 23 cfs was designed for Pond 4. • Peak flow from the Mountain’s Edge site contributing to Dixon Creek based on differing peaking times for the undetained basin and detained basins during a100- year event. ▪ During a 100-year event, the peak flow from the Mountain’s Edge development to Dixon Creek is 10.10 cfs. This was determined by disallowing flows from Basin OS2 through the existing culvert. • Total flow in Dixon Creek based on the detained flows from Mountain’s Edge, undetained basins from Mountain’s Edge and upstream undetained off-site Basin OS2. ▪ During a 100-year event, the peak flow in Dixon Creek, along the Mountain’s Edge property, is 27.33 cfs. This flow accounts for the undetained basin UD2, the detention pond releases, and the flow from off-site basin OS2. D. Overtopping Analysis for Storm Line 10 1. Storm Line 10 collects stormwater discharge from Basins A3-A7. As this area is intended as a pedestrian-friendly gathering area, the storm infrastructure was designed to limit the amount of obstruction within this area and provide the most usable area. 2. Previously, this area was designed to convey the full 100-year flow in a channel. In order to be more pedestrian friendly, the 100-year conveyance was split to provide an underground storm pipe for minor flows and a surface overtopping for 100-year flows. 3. Storm Line 10 was designed to convey the full 100-year flow from Basins A3 and A4 combined with the 2-year flows from Basins A5, A6, and A7. 4. The inlets for Basins A4 and A5 were designed to collect the full 100-year flow. The inlets for Basin A7 were designed to collect the 2-year flow. 5. Difference of the 100-year and 2-year flow for Basins A5, A6, and A7 was designed to overtop the pedestrian gather areas and be conveyed to Detention Pond 1 via surface channel. 6. The HY-8 model shows a flow depth of 6” in the gathering areas. The buildings were set at least 1’ above the 100-year overtopping water surface elevation. Mountain’s Edge Final Drainage Report 15 E. Specific Details 1. Inlets were designed utilizing either Urban Drainage spreadsheets for curb inlets or area inlets spreadsheets. All inlets, except a couple inlets for Storm Line 10, were designed to collect the 100-year flow. 2. Storm sewers were modeled utilizing Hydroflow for AutoCAD. All stormlines, except Storm Line 10, were designed to convey the full 100-year flow. 3. In lieu of riprap, erosion control mats were designed for the outfalls for each stormline. 4. Multiple landscape drains were designed to collect relatively small areas of landscaping and roofs. These drains have the capacity to collect the 100-year discharge from the small areas, but these drains were also designed to overtop the sidewalk in the case of a clogged inlet. As such, these landscape drains are not included in the detailed drainage design. V. CONCLUSIONS A. Compliance with Standards 1. The drainage design proposed with the Mountain’s Edge project complies with the City of Fort Collins’ Stormwater Criteria Manual. 2. The drainage design proposed with the Mountain’s Edge project complies with the City of Fort Collins’ Master Drainage Plan for the Spring Creek Basin and Canal Importation Basin. 3. There are no regulatory floodplains associated with the development. 4. The drainage plan and stormwater management measures proposed with the development are compliant with all applicable State and Federal regulations governing stormwater discharge. 5. The site achieves LID treatment for 49.4% of total impervious areas. This is 0.6% below the requirements set forth by the City of Fort Collins for Low Impact Development (LID). Please see LID Exhibit located in the Appendix. B. Drainage Concept 1. The drainage design proposed with this project will effectively comply with the Fort Collins Master Drainage Plan and will limit any potential damage or erosion associated with its stormwater runoff. All existing downstream drainage facilities are not expected to be impacted negatively by this development 2. The drainage design is anticipated to be very conservative. We have omitted any runoff reduction that will manifest due to infiltration within rain gardens. This is currently unable to be calculated with available soils data. Mountain’s Edge Final Drainage Report 16 References 1. Fort Collins Stormwater Criteria Manual, City of Fort Collins, Colorado, as adopted by Ordinance No. 174, 2011, and referenced in Section 26-500 (c) of the City of Fort Collins Municipal Code. 2. Preliminary Geotechnical Subsurface Exploration Report Proposed Single-Family Residential Development Herring Property – 2430 South Overland Trail, Fort Collins, Colorado, June 11, 2015, Soilogic, Inc. (Soilogic Project No. 15-1132). 3. Larimer County Urban Area Street Standards, Adopted January 2, 2001, Repealed and Reenacted, Effective October 1, 2002, Repealed and Reenacted, Effective April 1, 2007. 4. Soils Resource Report for Larimer County Area, Colorado, Natural Resources Conservation Service, United States Department of Agriculture. 5. Urban Storm Drainage Criteria Manual, Volumes 1-3, Urban Drainage and Flood Control District, Wright-McLaughlin Engineers, Denver, Colorado, Revised April 2008. APPENDIX A HYDROLOGIC COMPUTATIONS Mountain's Edge CHARACTER OF SURFACE 1 : Runoff Coefficient Percentage Impervious Project: Mountain's Edge Streets, Parking Lots, Roofs, Alleys, and Drives: Calculations By: S. Thomas Asphalt ……....……………...……….....…...……………….………………………………………………………….0.95 . 100% Date: December 20, 2016 Concrete …….......……………….….……….………………..….…………………………………………………….0.95 . 90% Gravel (packed) ……….…………………….….…………………………..………………………………………….0.50 . 40% Roofs …….…….………………..……………….……………………………………………………………………… 0.95 90% Pavers…………………………...………………..……………………………………………………………………… 0.40 22% Lawns and Landscaping Sandy Soil Flat <2% ……………………………………………………………………………………………………………… 0.10 0% Average 2% to 7% ………………………………………………………………………………………………….0.15 . 0% Steep >7% …………………………………………………………………………………………………………… 0.20 0% Clayey Soil Flat <2% ……………………………………………………………………………………………………………… 0.20 0% Average 2% to 7% ………………………………………………………………………………………………….0.25 . 0% Steep >7% …………………………………………………………………………………………………………… 0.35 0% 2-year Cf = 1.00 10-year Cf = 1.00 100-year Cf = 1.25 Runoff Coefficients are taken from the Fort Collins Stormwater Criteria Manual, Table RO-11 Sub-Basin ID Sub- BasinBasin Area (ac) Area of Asphalt (ac) Area of Concrete (ac) Area of Pavers (ac) Area of Roofs (ac) Soil Type and Average Slope Area of Lawns and Landscaping (ac) 2-year Composite Runoff Coefficient 10-year Composite Runoff Coefficient 100-year Composite Runoff Coefficient Composite % Imperv. HA1 4.07 0.00 0.00 0.00 0.00 Clayey | Average 2% to 7% 4.075 0.25 0.25 0.31 0% Mountain's Edge Overland Flow, Time of Concentration: Mountain's Edge Gutter/Swale Flow, Time of Concentration: Tt = L / 60V Tc = Ti + Tt (Equation RO-2) Velocity (Gutter Flow), V = 20·S½ Velocity (Swale Flow), V = 15·S½ NOTE: C-value for overland flows over grassy surfaces; C = 0.25 Is Length >500' ? C*Cf (2-yr Cf=1.00) C*Cf (10-yr Cf=1.00) C*Cf (100-yr Cf=1.25) Length, L (ft) Slope, S (%) Ti 2-yr (min) Ti 10-yr (min) Ti 100-yr (min) Length, L (ft) Slope, S (%) Velocity, V (ft/s) Tt (min) 2-yr Tc (min) 10-yr Tc (min) 100-yr Tc (min) 1 HA1 No 0.25 0.25 0.31 87 11.64% 6.5 6.5 6.1 681 0.94% 1.46 7.8 14.3 14.3 13.9 1 HA2 Yes 0.25 0.25 0.31 547 3.21% 25.2 25.2 23.4 583 0.96% 1.47 6.6 31.8 31.8 29.9 1 HA3 Yes 0.57 0.57 0.71 620 2.89% 17.4 17.4 12.8 583 0.96% 1.47 6.6 24.0 24.0 19.4 2 HB1 No 0.25 0.25 0.31 252 5.17% 14.6 14.6 13.5 590 0.94% 1.45 6.8 21.4 21.4 20.3 2 HB2 No 0.57 0.57 0.71 252 5.17% 9.1 9.1 6.7 590 0.94% 1.45 6.8 15.9 15.9 13.5 Mountain's Edge Rational Method Equation: Project: Mountain's Edge Calculations By: Date: Rainfall Intensity: 1 HA1 4.07 14 14 14 0.25 0.25 0.31 1.92 3.29 6.82 1.96 3.35 8.68 1 HA2 4.18 32 32 30 0.25 0.25 0.31 1.26 2.14 4.56 1.31 2.24 5.95 1 HA3 0.33 24 24 19 0.57 0.57 0.71 1.48 2.52 5.75 0.27 0.47 1.33 2 HB1 5.60 21 21 20 0.25 0.25 0.31 1.56 2.67 5.60 2.18 3.74 9.80 2 HB2 0.47 16 16 13 0.57 0.57 0.71 1.84 3.14 6.92 0.49 0.83 2.29 3 HB3 4.66 37 37 34 0.25 0.25 0.31 1.13 1.93 4.16 1.32 2.25 6.06 EXISTING RUNOFF COMPUTATIONS C100 Design Point Flow, Q100 (cfs) Flow, Q2 (cfs) 10-yr Tc (min) 2-yr Tc (min) C2 Flow, Q10 (cfs) Intensity, i100 (in/hr) Sub-Basin(s) S. Thomas Rainfall Intensity taken from the Fort Collins Stormwater Criteria Manual (FCSCM), Tables RA-7 and RA-8 December 20, 2016 Intensity, i10 (in/hr) C10 Area, A (acres) Intensity, i2 (in/hr) 100-yr Tc (min) Q = C f ( C )( i )( A ) 12/20/2016 3:48 PM D:\Projects\911-007\Drainage\Hydrology\911-007_Existing_Rational_Calcs.xlsx\Runoff Mountain's Edge CHARACTER OF SURFACE 1 : Runoff Coefficient Percentage Impervious Project: Mountain's Edge Streets, Parking Lots, Roofs, Alleys, and Drives: Calculations By: S. Thomas Asphalt ……....……………...……….....…...……………….………………………………………………………….0.95 100% . Date: February 17, 2018 Concrete …….......……………….….……….………………..….…………………………………………………….0.95 90% . Gravel (packed) ……….…………………….….…………………………..………………………………………….0.50 . 40% Roofs …….…….………………..……………….……………………………………………………………………… 0.95 90% Single Family Lots 0.55 50% Lawns and Landscaping Sandy Soil Flat <2% ……………………………………………………………………………………………………………… 0.10 0% Average 2% to 7% ………………………………………………………………………………………………….0.15 . 0% Steep >7% ……………………………………………………………………………………………0.………………20 0% Clayey Soil Flat <2% ……………………………………………………………………………………………………………… 0.20 0% Average 2% to 7% ………………………………………………………………………………………………….0.25 . 0% Steep >7% ……………………………………………………………………………………………0.………………35 0% 2-year Cf = 1.00 10-year Cf = 1.00 100-year C f = 1.25 Runoff Coefficients are taken from the Fort Collins Stormwater Criteria Manual, Table RO-11 Sub-Basin ID Sub- BasinBasin Area (ac) Area of Asphalt (ac) Area of Gravel (ac) Area of Concrete (ac) Area of Single-Family Lots (ac) Area of Roofs (ac) Soil Type and Average Slope Area of Lawns and Landscaping (ac) 2-year Composite Runoff Coefficient 10-year Composite Runoff Coefficient Mountain's Edge Overland Flow, Time of Concentration: Mountain's Edge Gutter/Swale Flow, Time of Concentration: Tt = L / 60V Tc = T i + Tt (Equation RO-2) Velocity (Gutter Flow), V = 20·S ½ Velocity (Swale Flow), V = 15·S ½ NOTE: C-value for overland flows over grassy surfaces; C = 0.25 Is Length >500' ? C*Cf (2-yr Cf=1.00) C*Cf (10-yr Cf=1.00) C*Cf (100-yr Cf=1.25) Length, L (ft) Slope, S (%) Ti 2-yr (min) Ti 10-yr (min) Ti 100-yr (min) Length, L (ft) Slope, S (%) Velocity, V (ft/s) Tt (min) Length, L (ft) Slope, S (%) Velocity, V (ft/s) Tt Mountain's Edge Rational Method Equation: Project: Mountain's Edge Calculations By: Date: Rainfall Intensity: A1 A1 1.45 5 5 5 0.74 0.74 0.92 2.85 4.87 9.95 3.04 5.19 13.25 A2 A2 0.27 5 5 5 0.59 0.59 0.73 2.85 4.87 9.95 0.45 0.76 1.95 A3 A3 0.23 5 5 5 0.57 0.57 0.71 2.85 4.87 9.95 0.38 0.64 1.64 A4 A4 0.25 5 5 5 0.58 0.58 0.72 2.85 4.87 9.95 0.42 0.72 1.83 A5 A5 1.14 7 7 6 0.89 0.89 1.00 2.60 4.44 9.63 2.63 4.49 10.95 A6 A6 0.34 5 5 5 0.67 0.67 0.83 2.85 4.87 9.95 0.65 1.12 2.86 A7 A7 0.41 13 13 10 0.55 0.55 0.69 2.02 3.45 7.88 0.45 0.77 2.21 A8 A8 1.54 9 9 8 0.41 0.41 0.52 2.30 3.93 8.38 1.46 2.50 6.66 A8 TOTAL BASIN A 5.77 15 15 13 0.62 0.62 0.78 1.90 3.24 6.92 6.83 11.68 31.18 B1 B1 0.42 5 5 5 0.95 0.95 1.00 2.85 4.87 9.95 1.13 1.93 4.14 B2 B2 0.62 6 6 5 0.59 0.59 0.74 2.67 4.56 9.95 0.98 1.68 4.57 B3 B3 1.22 5 5 5 0.83 0.83 1.00 2.85 4.87 9.95 2.86 4.90 12.10 B4 B4 0.06 5 5 5 0.72 0.72 0.90 2.85 4.87 9.95 0.12 0.20 0.52 B5 B5 0.19 5 5 5 0.78 0.78 0.98 2.85 4.87 9.95 0.42 0.71 1.82 B6 B6 0.40 10 10 9 0.50 0.50 0.62 2.21 3.78 8.03 0.44 0.76 2.02 B7 B7 1.09 7 7 6 0.30 0.30 0.38 2.60 4.44 9.31 0.86 1.47 3.85 B6 TOTAL BASIN B 3.99 10 10 8 0.62 0.62 0.78 2.26 3.86 8.38 5.61 9.59 26.07 C1 C1 0.15 5 5 5 0.56 0.56 0.70 2.85 4.87 9.95 0.25 0.42 1.08 C2 C2 0.48 6 6 5 0.39 0.39 0.48 2.76 4.72 9.95 0.51 0.87 2.31 C2 TOTAL BASIN C 0.64 6 6 5 0.43 0.43 0.54 2.76 4.72 9.95 0.75 1.29 3.39 D1 D1 0.25 5 5 5 0.95 0.95 1.00 2.85 4.87 9.95 0.68 1.16 2.50 D2 D2 1.66 5 5 5 0.71 0.71 0.89 2.85 4.87 9.95 3.36 5.73 14.65 D3 D3 0.88 5 5 5 0.75 0.75 0.94 2.85 4.87 9.95 1.88 3.22 8.22 D4 D4 0.65 5 5 5 0.70 0.70 0.88 2.85 4.87 9.95 1.30 2.22 5.67 D5 D5 0.89 8 8 7 0.42 0.42 0.53 2.40 4.10 8.80 0.90 1.54 4.13 D6 D6 0.57 7 7 6 0.39 0.39 0.48 2.52 4.31 9.31 0.56 0.95 2.57 D6 TOTAL BASIN D 4.89 6 6 5 0.64 0.64 0.80 2.76 4.72 9.95 8.64 14.76 38.92 UD1 UD1 0.05 5 5 5 0.83 0.83 1.00 2.85 4.87 9.95 0.12 0.21 0.52 UD2 UD2 4.05 14 14 14 0.26 0.26 0.33 1.92 3.29 6.82 2.04 3.49 9.04 HT1 HT1 16.86 37 37 32 0.39 0.39 0.49 1.14 1.95 4.38 7.50 12.80 36.00 OS1 OS1 14.72 24 24 23 0.33 0.33 0.41 1.48 2.52 5.20 7.06 12.06 31.10 Area, A (acres) Intensity, i2 (in/hr) 100-yr Tc (min) PROPOSED RUNOFF COMPUTATIONS C100 Design Point Flow, Q100 (cfs) Flow, Q2 (cfs) 10-yr Tc (min) 2-yr Tc (min) APPENDIX B HYDRAULIC COMPUTATIONS B.1 DETENTION PONDS B.2 WATER QUALITY B.3 STORM SEWER B.4 INLETS B.5 OVERTOPPING ANALYSIS B.6 OVERFLOW WEIRS B.7 EROSION CONTROL MAT APPENDIX B.1 DETENTION PONDS Mountain's Edge 911-007 Fort Collins, Colorado S. Thomas Date: 2/17/2018 Pond No.: 1 Pond 1 100-yr 0.78 WQCV 3251 ft 3 Area (A)= 5.68 acres Quantity Detention SWMM 61985 ft 3 Max Release Rate = 0.35 cfs Total Volume 61985 ft 3 Total Volume 1.423 ac-ft *SWMM Model accounts for initial WQCV depth in pond prior to beginning of storm. Therefore, SWMM volume includes WQCV as additional. Detention Pond Calculation | SWMM Method Project Number: Project Location: Calculations By: Input Variables Results Design Point Design Storm Required Detention Volume Developed "C" = 2/17/2018 3:36 PM D:\Projects\911-007\Drainage\Detention\911-007_Detention Pond 1.xlsm\SWMM_FC Mountain's Edge 911-007 Fort Collins, CO S. Thomas Date: 2/17/2018 Pond No.: 1 Pond 1 WQCV 3251 ft3 5141.81 ft. Design Storm 100-yr Required Volume= 61985 ft3 5145.31 ft. Contour Elevation (Y- values) Contour Area Depth Incremental Area Avg. End Cumulative Volume Avg. End Incremental Volume Conic Cummulative Volume Conic (X- values) ft3 ft. ft3 ft3 ft3 ft3 5,140.20 56 0.00 0 0 0 0 5,140.40 248 0.20 30 30 28 28 5,140.60 558 0.20 81 111 79 107 5,140.80 991 0.20 155 266 153 259 5,141.00 1572 0.20 256 522 254 513 5,141.20 2314 0.20 389 911 386 900 5,141.40 3228 0.20 554 1465 552 1451 5,141.60 4344 0.20 757 2222 754 2206 5,141.80 5674 0.20 1002 3224 999 3205 5,142.00 7191 0.20 1286 4510 1283 4488 5,142.20 8865 0.20 1606 6116 1603 6091 5,142.40 10469 0.20 1933 8049 1931 8022 5,142.60 11917 0.20 2239 10288 2237 10259 5,142.80 13191 0.20 2511 12799 2510 12769 5,143.00 14306 0.20 2750 15548 2749 15517 5,143.20 15372 0.20 2968 18516 2967 18485 5,143.40 16455 0.20 3183 21699 3182 21667 5,143.60 17573 0.20 3403 25102 3402 25069 5,143.80 18716 0.20 3629 28731 3628 28697 5,144.00 19883 0.20 3860 32590 3859 32557 5,144.20 20810 0.20 4069 36660 4069 36626 5,144.40 21,612 0.20 4242 40902 4242 40867 5,144.60 22,320 0.20 4393 45295 4393 45260 5,144.80 23,022 0.20 4534 49829 4534 49795 5,145.00 23,739 0.20 4676 54505 4676 54470 5,145.20 24,470 0.20 4821 59326 4821 59291 5,145.40 25,217 0.20 4969 64295 4968 64260 Design Point Design Storm Require Volume= Stage - Storage Calculation Project Number: Project Location: Calculations By: Mountain's Edge ORIFICE RATING CURVE Pond 1 100-yr Orifice Project: Mountain's Edge Date: 2/17/2018 By: S. Thomas 100-yr WSEL= 5145.31 Orifice Plate Outflow Q 0.35 cfs Orifice Coefficient Cd 0.65 Gravity Constant g 32.2 ft/s^2 100-year head H 5.31 ft Orifice Area Ao 0.03 ft^2 Orifice Area Ao 4.19 in^2 Radius r 1.2 in Diameter d 2.3 in Orifice Curve Stage (ft) H (ft) Q (cfs) SWMM Stage Note 5140.00 0.00 0.00 0.00 Pond Invert 5140.50 0.50 0.11 0.50 5141.00 1.00 0.15 1.00 5141.50 1.50 0.19 1.50 5142.00 2.00 0.21 2.00 5142.50 2.50 0.24 2.50 5143.00 3.00 0.26 3.00 5143.50 3.50 0.28 3.50 5144.00 4.00 0.30 4.00 5144.50 4.50 0.32 4.50 5145.00 5.00 0.34 5.00 5145.31 5.31 0.35 5.31 100-yr WSEL 5145.50 5.50 0.36 5.50 5146.00 6.00 0.37 6.00 5146.50 6.50 0.39 6.50 5147.00 7.00 0.40 7.00 2/17/2018 3:42 PM D:\Projects\911-007\Drainage\Detention\911-007_Pond 1 100-yr Restrictor.xlsx\Orifice Size Mountain's Edge 911-007 Fort Collins, Colorado S. Thomas Date: 2/17/2018 Pond No.: Pond 2 Pond 2 100-yr 0.78 WQCV 2987 ft 3 Area (A)= 4.09 acres Quantity Detention from SWMM 45425 ft 3 Max Release Rate = 0.40 cfs Total Volume 45425 ft 3 Total Volume 1.043 ac-ft *SWMM Model accounts for initial WQCV depth in pond prior to beginning of storm. Therefore, SWMM volume includes WQCV as additional. Detention Pond Calculation | SWMM Method Project Number: Project Location: Calculations By: Input Variables Results Design Point Design Storm Required Detention Volume Developed "C" = 2/17/2018 3:38 PM D:\Projects\911-007\Drainage\Detention\911-007_Detention Pond 2.xlsm\SWMM_FC Mountain's Edge 911-007 Fort Collins, CO S. Thomas Date: 2/17/2018 Pond No.: Pond 2 Pond 2 WQCV 2987 ft3 5137.87 ft. Design Storm 100-yr Required Volume= 45425 ft3 5140.04 ft. Contour Elevation (Y- values) Contour Area Depth Incremental Area Avg. End Cumulative Volume Avg. End Incremental Volume Conic Cummulative Volume Conic (X- values) ft3 ft. ft3 ft3 ft3 ft3 5,137.20 238 0.00 0 0 0 0 5,137.40 1614 0.20 185 185 165 165 5,137.60 4877 0.20 649 834 620 785 5,137.80 9379 0.20 1426 2260 1401 2186 5,138.00 13640 0.20 2302 4562 2289 4474 5,138.20 17021 0.20 3066 7628 3060 7534 5,138.40 18800 0.20 3582 11210 3581 11115 5,138.60 19491 0.20 3829 15039 3829 14944 5,138.80 19938 0.20 3943 18982 3943 18887 5,139.00 20399 0.20 4034 23016 4034 22920 5,139.20 20875 0.20 4127 27143 4127 27048 5,139.40 21370 0.20 4224 31368 4224 31272 5,139.60 21877 0.20 4325 35692 4325 35597 5,139.80 22435 0.20 4431 40123 4431 40028 5,140.00 23229 0.20 4566 44690 4566 44594 5,140.20 24094 0.20 4732 49422 4732 49326 5,140.40 24959 0.20 4905 54327 4905 54231 Design Point Design Storm Require Volume= Stage - Storage Calculation Project Number: Project Location: Calculations By: Required Volume Water Surface Elevation (WSE) 2/17/20183:38 PM D:\Projects\911-007\Drainage\Detention\911-007_Detention Pond 2.xlsm\Stage_Storage Mountain's Edge ORIFICE RATING CURVE Pond 2 100-yr Orifice Project: Mountain's Edge Date: 2/17/2018 By: S. Thomas 100-yr WSEL= 5140.04 Orifice Plate Outflow Q 0.4 cfs Orifice Coefficient Cd 0.65 Gravity Constant g 32.2 ft/s^2 100-year head H 3.04 ft Orifice Area Ao 0.04 ft^2 Orifice Area Ao 6.33 in^2 Radius r 1.4 in Diameter d 2.8 in Orifice Curve Stage (ft) H (ft) Q (cfs) SWMM Stage Note 5137.00 0.00 0.00 0.00 Pond Invert 5137.50 0.50 0.16 0.50 5138.00 1.00 0.23 1.00 5138.50 1.50 0.28 1.50 5139.00 2.00 0.32 2.00 5139.50 2.50 0.36 2.50 5140.00 3.00 0.40 3.00 5140.04 3.04 0.40 3.04 5140.50 3.50 0.43 3.50 5141.00 4.00 0.46 4.00 5141.50 4.50 0.49 4.50 5142.00 5.00 0.51 5.00 5142.50 5.50 0.54 5.50 5143.00 6.00 0.56 6.00 5143.50 6.50 0.58 6.50 5144.00 7.00 0.61 7.00 2/17/2018 3:42 PM D:\Projects\911-007\Drainage\Detention\911-007_Pond 2 100-yr Restrictor.xlsx\Orifice Size Mountain's Edge 911-007 Fort Collins, Colorado S. Thomas Date: 2/17/2018 Pond No.: Pond 3 Pond 3 100-yr 0.54 WQCV 296 ft 3 Area (A)= 0.64 acres Quantity Detention from SWMM 5898 ft 3 Max Release Rate = 0.10 cfs Total Volume 5898 ft 3 Total Volume 0.135 ac-ft *SWMM Model accounts for initial WQCV depth in pond prior to beginning of storm. Therefore, SWMM volume includes WQCV as additional. Detention Pond Calculation | SWMM Method Project Number: Project Location: Calculations By: Input Variables Results Design Point Design Storm Required Detention Volume Developed "C" = 2/17/2018 3:39 PM D:\Projects\911-007\Drainage\Detention\911-007_Detention Pond 3.xlsm\SWMM_FC Mountain's Edge 911-007 Fort Collins, CO S. Thomas Date: 2/17/2018 Pond No.: Pond 3 Pond 3 WQCV 296 ft3 5143.01 ft. Design Storm 100-yr Required Volume= 5898 ft3 5145.62 ft. Contour Elevation (Y- values) Contour Area Depth Incremental Area Avg. End Cumulative Volume Avg. End Incremental Volume Conic Cummulative Volume Conic (X- values) ft3 ft. ft3 ft3 ft3 ft3 5,142.20 43 0.00 0 0 0 0 5,142.40 154 0.20 20 20 19 19 5,142.60 321 0.20 47 67 46 65 5,142.80 544 0.20 86 154 85 150 5,143.00 814 0.20 136 289 135 285 5,143.20 1,114 0.20 193 482 192 477 5,143.40 1,370 0.20 248 730 248 725 5,143.60 1,525 0.20 289 1020 289 1014 5,143.80 1,685 0.20 321 1341 321 1335 5,144.00 1,850 0.20 354 1694 353 1689 5,144.20 2,022 0.20 387 2082 387 2076 5,144.40 2,199 0.20 422 2504 422 2498 5,144.60 2,384 0.20 458 2962 458 2956 5,144.80 2,575 0.20 496 3458 496 3452 5,145.00 2,773 0.20 535 3993 535 3986 5,145.20 2,979 0.20 575 4568 575 4562 5,145.40 3,191 0.20 617 5185 617 5178 5,145.60 3,412 0.20 660 5845 660 5839 5,145.80 3,642 0.20 705 6551 705 6544 Design Point Design Storm Require Volume= Stage - Storage Calculation Project Number: Project Location: Calculations By: Required Volume Water Surface Elevation (WSE) 2/17/20183:39 PM D:\Projects\911-007\Drainage\Detention\911-007_Detention Pond 3.xlsm\Stage_Storage Mountain's Edge ORIFICE RATING CURVE Pond 3 100-yr Orifice Project: Mountain's Edge Date: 2/17/2018 By: S. Thomas 100-yr WSEL= 5145.62 Orifice Plate Outflow Q 0.1 cfs Orifice Coefficient Cd 0.65 Gravity Constant g 32.2 ft/s^2 100-year head H 3.51 ft Orifice Area Ao 0.01 ft^2 Orifice Area Ao 1.47 in^2 Radius r 0.7 in Diameter d 1.4 in Orifice Curve Stage (ft) H (ft) Q (cfs) SWMM Stage Note 5142.11 0.00 0.00 0.00 Pond Invert 5142.61 0.50 0.04 0.50 5143.11 1.00 0.05 1.00 5143.61 1.50 0.07 1.50 5144.11 2.00 0.08 2.00 5144.61 2.50 0.08 2.50 5145.11 3.00 0.09 3.00 5145.61 3.50 0.10 3.50 5145.62 3.51 0.10 3.51 100-yr WSEL 5146.11 4.00 0.11 4.00 5146.61 4.50 0.11 4.50 5147.11 5.00 0.12 5.00 5147.61 5.50 0.13 5.50 5148.11 6.00 0.13 6.00 5148.61 6.50 0.14 6.50 5149.11 7.00 0.14 7.00 2/17/2018 3:43 PM D:\Projects\911-007\Drainage\Detention\911-007_Pond 3 100-yr Restrictor.xlsx\Orifice Size Mountain's Edge 911-007 Fort Collins, Colorado S. Thomas Date: 2/17/2018 Pond No.: 4 Pond 4 100-yr 0.80 WQCV 970 ft 3 Area (A)= 4.89 acres Quantity Detention from SWMM 44727 ft 3 Max Release Rate = 1.4 cfs Total Volume 44727 ft 3 Total Volume 1.027 ac-ft *SWMM Model accounts for initial WQCV depth in pond prior to beginning of storm. Therefore, SWMM volume includes WQCV as additional. Detention Pond Calculation | SWMM Method Project Number: Project Location: Calculations By: Input Variables Results Design Point Design Storm Required Detention Volume Developed "C" = 2/17/2018 3:40 PM D:\Projects\911-007\Drainage\Detention\911-007_Detention Pond 4.xlsm\SWMM_FC Mountain's Edge 911-007 Fort Collins, CO S. Thomas Date: 2/17/2018 Pond No.: 4 Pond 4 WQCV 970 ft3 5136.45 ft. Design Storm 100-yr Required Volume= 44727 ft3 5142.04 ft. Contour Elevation (Y- values) Contour Area Depth Incremental Area Avg. End Cumulative Volume Avg. End Incremental Volume Conic Cummulative Volume Conic (X- values) ft3 ft. ft3 ft3 ft3 ft3 5,135.40 2 0.00 0 0 0 0 5,135.60 201 0.20 20 20 15 15 5,135.80 556 0.20 76 96 73 88 5,136.00 1007 0.20 156 252 154 242 5,136.20 1531 0.20 254 506 252 494 5,136.40 2038 0.20 357 863 356 849 5,136.60 2544 0.20 458 1321 457 1307 5,136.80 3030 0.20 557 1879 557 1863 5,137.00 3318 0.20 635 2514 635 2498 5,137.20 3511 0.20 683 3196 683 3181 5,137.40 3707 0.20 722 3918 722 3903 5,137.60 3,906 0.20 761 4680 761 4664 5,137.80 4,112 0.20 802 5481 802 5465 5,138.00 4,324 0.20 844 6325 844 6309 5,138.20 4,545 0.20 887 7212 887 7196 5,138.40 4,775 0.20 932 8144 932 8128 5,138.60 5,016 0.20 979 9123 979 9107 5,138.80 5,276 0.20 1029 10152 1029 10136 5,139.00 5,567 0.20 1084 11237 1084 11220 5,139.20 5,834 0.20 1140 12377 1140 12360 5,139.40 6,113 0.20 1195 13572 1195 13555 5,139.60 6,382 0.20 1249 14821 1249 14804 5,139.80 9,105 0.20 1549 16370 1541 16345 5,140.00 9,693 0.20 1880 18249 1879 18224 5,140.20 10,291 0.20 1998 20248 1998 20222 5,140.40 10,907 0.20 2120 22368 2120 22342 5,140.60 11,532 0.20 2244 24612 2244 24585 5,140.80 12,168 0.20 2370 26982 2370 26955 5,141.00 12,825 0.20 2499 29481 2499 29454 5,141.20 13,488 0.20 2631 32112 2631 32085 5,141.40 14,170 0.20 2766 34878 2765 34851 5,141.60 14,873 0.20 2904 37782 2904 37755 5,141.80 15,591 0.20 3046 40829 3046 40801 5,142.00 16,330 0.20 3192 44021 3192 43993 Mountain's Edge ORIFICE RATING CURVE Pond 4 100-yr Orifice Project: Mountain's Edge Date: 2/17/2018 By: S. Thomas 100-yr WSEL= 5142.04 Orifice Plate Outflow Q 1.4 cfs Orifice Coefficient Cd 0.65 Gravity Constant g 32.2 ft/s^2 100-year head H 6.65 ft Orifice Area Ao 0.10 ft^2 Orifice Area Ao 14.99 in^2 Radius r 2.2 in Diameter d 4.4 in Orifice Curve Stage (ft) H (ft) Q (cfs) SWMM Stage Note 5135.39 0.00 0.00 0.00 Pond Invert 5135.89 0.50 0.38 0.50 5136.39 1.00 0.54 1.00 5136.89 1.50 0.66 1.50 5137.39 2.00 0.77 2.00 5137.89 2.50 0.86 2.50 5138.39 3.00 0.94 3.00 5138.89 3.50 1.02 3.50 5139.39 4.00 1.09 4.00 5139.89 4.50 1.15 4.50 5140.39 5.00 1.21 5.00 5140.89 5.50 1.27 5.50 5141.39 6.00 1.33 6.00 5141.89 6.50 1.38 6.50 5142.04 6.65 1.40 6.65 100-yr WSEL 5142.39 7.00 1.44 7.00 2/17/2018 3:44 PM D:\Projects\911-007\Drainage\Detention\911-007_Pond 4 100-yr Restrictor.xlsx\Orifice Size APPENDIX B.2 WATER QUALITY POND 1 Project: Mountain's Edge By: S. Thomas REQUIRED STORAGE & OUTLET WORKS: BASIN AREA (acres)= 5.770 <-- INPUT from impervious calcs BASIN IMPERVIOUSNESS PERCENT = 50.00 <-- INPUT from impervious calcs BASIN IMPERVIOUSNESS RATIO = 0.5000 <-- CALCULATED Drain Time (hrs) 40 <-- INPUT Drain Time Coefficient 1.0 <-- CALCULATED from Figure Table 3-2 WQCV (watershed inches) = 0.206 <-- CALCULATED from Figure 3-2 WQCV (ac-ft) = 0.099 <-- CALCULATED from UDFCD DCM V.3 Section 6.5 Rain Garden WQCV (ft 3 ) = 1069 <-- CALCULATED Adjusted WQCV (cu-ft) = 3251 <-- CALCULATED (minus Rain Garden) WQ Depth (ft) = 1.810 <-- INPUT from stage-storage table AREA REQUIRED PER ROW, a (in 2 ) = 0.248 <-- CALCULATED from Figure EDB-3 CIRCULAR PERFORATION SIZING: dia (in) = 5/9 <-- INPUT from Figure 5 number of rows = 5 t (in) = 0.500 <-- INPUT from Figure 5 number of columns = 1.000 <-- CALCULATED from WQ Depth and row spacing WATER QUALITY CONTROL STRUCTURE PLATE February 13, 2018 Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia = 65.0 % (100% if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio (i = Ia/100) 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 = 63,123 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV = 1,069 cu ft Vol = (WQCV / 12) * Area F) For Watersheds Outside of the Denver Region, Depth of d6 = in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VWQCV OTHER = cu ft Water Quality Capture Volume (WQCV) Design Volume H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER = cu ft (Only if a different WQCV Design Volume is desired) 2. Basin Geometry A) WQCV Depth (12-inch maximum) DWQCV = 12 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 AMin = 821 sq ft D) Actual Flat Surface Area AActual = 933 sq ft E) Area at Design Depth (Top Surface Area) ATop = 1577 sq ft F) Rain Garden Total Volume VT= 1,255 cu ft (VT= ((ATop + AActual) / 2) * Depth) 3. Growing Media 4. Underdrain System A) Are underdrains provided? B) Underdrain system orifice diameter for 12 hour drain time i) Distance From Lowest Elevation of the Storage y = ft Volume to the Center of the Orifice ii) Volume to Drain in 12 Hours Vol12 = N/A cu ft iii) Orifice Diameter, 3/8" Minimum DO = N/A in Design Procedure Form: Rain Garden (RG) Stephanie Thomas Northern Engineering February 17, 2018 Mountain's Edge - Rain Garden 1 Drake and Overland, Fort Collins, CO UD-BMP (Version 3.06, November 2016) Choose One Choose One 18" Rain Garden Growing Media Other (Explain): YES NO Rain Garden 1.xlsm, RG 2/17/2018, 4:45 PM POND 2 Project: Mountain's Edge By: S. Thomas REQUIRED STORAGE & OUTLET WORKS: BASIN AREA (acres)= 3.990 <-- INPUT from impervious calcs BASIN IMPERVIOUSNESS PERCENT = 50.00 <-- INPUT from impervious calcs BASIN IMPERVIOUSNESS RATIO = 0.5000 <-- CALCULATED Drain Time (hrs) 40 <-- INPUT Drain Time Coefficient 1.0 <-- CALCULATED from Figure Table 3-2 WQCV (watershed inches) = 0.206 <-- CALCULATED from Figure 3-2 WQCV (ac-ft) = 0.069 <-- CALCULATED from UDFCD DCM V.3 Section 6.5 Rain Garden WQCV (ft 3 ) = 0 <-- CALCULATED Adjusted WQCV (cu-ft) = 2987 <-- CALCULATED (minus Rain Garden) WQ Depth (ft) = 1.000 <-- INPUT from stage-storage table AREA REQUIRED PER ROW, a (in 2 ) = 0.278 <-- CALCULATED from Figure EDB-3 CIRCULAR PERFORATION SIZING: dia (in) = 3/5 <-- INPUT from Figure 5 number of rows = 3 t (in) = 0.500 <-- INPUT from Figure 5 number of columns = 1.000 <-- CALCULATED from WQ Depth and row spacing WATER QUALITY CONTROL STRUCTURE PLATE February 13, 2018 POND 3 Project: Mountain's Edge By: S. Thomas REQUIRED STORAGE & OUTLET WORKS: BASIN AREA (acres)= 0.640 <-- INPUT from impervious calcs BASIN IMPERVIOUSNESS PERCENT = 23.00 <-- INPUT from impervious calcs BASIN IMPERVIOUSNESS RATIO = 0.2300 <-- CALCULATED Drain Time (hrs) 40 <-- INPUT Drain Time Coefficient 1.0 <-- CALCULATED from Figure Table 3-2 WQCV (watershed inches) = 0.128 <-- CALCULATED from Figure 3-2 WQCV (ac-ft) = 0.007 <-- CALCULATED from UDFCD DCM V.3 Section 6.5 Rain Garden WQCV (ft 3 ) = 0 <-- CALCULATED Adjusted WQCV (cu-ft) = 296 <-- CALCULATED (minus Rain Garden) WQ Depth (ft) = 1.000 <-- INPUT from stage-storage table AREA REQUIRED PER ROW, a (in 2 ) = 0.031 <-- CALCULATED from Figure EDB-3 CIRCULAR PERFORATION SIZING: dia (in) = 1/5 <-- INPUT from Figure 5 number of rows = 3 t (in) = 0.500 <-- INPUT from Figure 5 number of columns = 1.000 <-- CALCULATED from WQ Depth and row spacing WATER QUALITY CONTROL STRUCTURE PLATE February 13, 2018 POND 4 Project: Mountain's Edge By: S. Thomas REQUIRED STORAGE & OUTLET WORKS: BASIN AREA (acres)= 4.890 <-- INPUT from impervious calcs BASIN IMPERVIOUSNESS PERCENT = 53.00 <-- INPUT from impervious calcs BASIN IMPERVIOUSNESS RATIO = 0.5300 <-- CALCULATED Drain Time (hrs) 40 <-- INPUT Drain Time Coefficient 1.0 <-- CALCULATED from Figure Table 3-2 WQCV (watershed inches) = 0.215 <-- CALCULATED from Figure 3-2 WQCV (ac-ft) = 0.087 <-- CALCULATED from UDFCD DCM V.3 Section 6.5 Rain Garden WQCV (ft 3 ) = 2843 <-- CALCULATED Adjusted WQCV (cu-ft) = 970 <-- CALCULATED (minus Rain Garden) WQ Depth (ft) = 1.060 <-- INPUT from stage-storage table AREA REQUIRED PER ROW, a (in 2 ) = 0.094 <-- CALCULATED from Figure EDB-3 CIRCULAR PERFORATION SIZING: dia (in) = 1/3 <-- INPUT from Figure 5 number of rows = 3 t (in) = 0.500 <-- INPUT from Figure 5 number of columns = 1.000 <-- CALCULATED from WQ Depth and row spacing WATER QUALITY CONTROL STRUCTURE PLATE February 17, 2018 Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia = 57.0 % (100% if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio (i = Ia/100) i = 0.570 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 = 188,303 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV = 2,843 cu ft Vol = (WQCV / 12) * Area F) For Watersheds Outside of the Denver Region, Depth of d6 = in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VWQCV OTHER = cu ft Water Quality Capture Volume (WQCV) Design Volume H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER = cu ft (Only if a different WQCV Design Volume is desired) 2. Basin Geometry A) WQCV Depth (12-inch maximum) DWQCV = 12 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 AMin = 2147 sq ft D) Actual Flat Surface Area AActual = 2334 sq ft E) Area at Design Depth (Top Surface Area) ATop = 3974 sq ft F) Rain Garden Total Volume VT= 3,154 cu ft (VT= ((ATop + AActual) / 2) * Depth) 3. Growing Media 4. Underdrain System A) Are underdrains provided? B) Underdrain system orifice diameter for 12 hour drain time i) Distance From Lowest Elevation of the Storage y = ft Volume to the Center of the Orifice ii) Volume to Drain in 12 Hours Vol12 = N/A cu ft iii) Orifice Diameter, 3/8" Minimum DO = N/A in Design Procedure Form: Rain Garden (RG) Stephanie Thomas Northern Engineering February 17, 2018 Mountain's Edge - Rain Garden 2 Drake and Overland, Fort Collins CO UD-BMP (Version 3.06, November 2016) Choose One Choose One 18" Rain Garden Growing Media Other (Explain): YES NO Rain Garden 2.xlsm, RG 2/17/2018, 4:45 PM APPENDIX B.3 STORM SEWERS APPENDIX B.4 INLETS Area Inlet Performance Curve: Design Point A2 - Inline Drain 12-3 Governing Equations: At low flow depths, the inlet will act like a weir governed by the following equation: * where P = 2(L + W) * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of the inlet grate * where H corresponds to the depth of water above the centroid of the cross-sectional area (A) The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown. However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation will cross at a certain flow depth. The two curves can be found below: If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters: Type of Grate: 15" ADS Drop In Grate 1599CGD Shape Circular Length of Grate (ft): 1.25 Width of Grate (ft): 1.25 Open Area of Grate (ft 2 ): 0.85 Flowline Elevation (ft): 5149.270 Allowable Capacity: 50% Depth vs. Flow: Depth Above Inlet (ft) Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs) 0.00 5149.27 0.00 0.00 0.00 0.10 5149.37 0.19 0.72 0.19 0.20 5149.47 0.53 1.02 0.53 0.30 5149.57 0.97 1.25 0.97 0.40 5149.67 1.49 1.44 1.44 0.50 5149.770 2.08 1.62 1.62 0.60 5149.87 2.74 1.77 1.77 0.70 5149.97 3.45 1.91 1.91 Q100 0.80 5150.07 4.21 2.04 2.04 0.90 5150.17 5.03 2.17 2.17 1.00 5150.270 5.89 2.28 2.28 Inlet at Design Point A2 is designed to intercept the full 100-yr flow of 1.95 cfs at the elevation 5150.00 0.00 1.00 2.00 3.00 4.00 5.00 6.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 Discharge (cfs) Stage (ft) Stage - Discharge Curves Weir Flow Area Inlet Performance Curve: Design Point A3 - Inline Drain 10-3A Governing Equations: At low flow depths, the inlet will act like a weir governed by the following equation: * where P = 2(L + W) * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of the inlet grate * where H corresponds to the depth of water above the centroid of the cross-sectional area (A) The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown. However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation will cross at a certain flow depth. The two curves can be found below: If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters: Type of Grate: 15" ADS Drop In Grate 1599CGD Shape Circular Length of Grate (ft): 1.25 Width of Grate (ft): 1.25 Open Area of Grate (ft 2 ): 0.85 Flowline Elevation (ft): 5148.230 Allowable Capacity: 50% Depth vs. Flow: Depth Above Inlet (ft) Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs) 0.00 5148.23 0.00 0.00 0.00 0.10 5148.33 0.19 0.72 0.19 0.20 5148.43 0.53 1.02 0.53 0.30 5148.53 0.97 1.25 0.97 0.40 5148.63 1.49 1.44 1.44 0.50 5148.730 2.08 1.62 1.62 100-year 0.60 5148.83 2.74 1.77 1.77 0.70 5148.93 3.45 1.91 1.91 0.80 5149.03 4.21 2.04 2.04 0.90 5149.13 5.03 2.17 2.17 1.00 5149.230 5.89 2.28 2.28 Inlet at Design Point A3 is designed to intercept the full 100-yr flow of 1.64 cfs at the elevation 5148.74 0.00 1.00 2.00 3.00 4.00 5.00 6.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 Discharge (cfs) Stage (ft) Stage - Discharge Curves Weir Flow Area Inlet Performance Curve: Design Point A4 - Inline Drain 10-7D Governing Equations: At low flow depths, the inlet will act like a weir governed by the following equation: * where P = 2(L + W) * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of the inlet grate * where H corresponds to the depth of water above the centroid of the cross-sectional area (A) The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown. However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation will cross at a certain flow depth. The two curves can be found below: If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters: Type of Grate: 15" ADS Drop In Grate 1599CGD Shape Circular Length of Grate (ft): 1.25 Width of Grate (ft): 1.25 Open Area of Grate (ft 2 ): 0.85 Flowline Elevation (ft): 5147.240 Allowable Capacity: 50% Depth vs. Flow: Depth Above Inlet (ft) Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs) 0.00 5147.24 0.00 0.00 0.00 0.10 5147.34 0.19 0.72 0.19 0.20 5147.44 0.53 1.02 0.53 0.30 5147.54 0.97 1.25 0.97 0.40 5147.64 1.49 1.44 1.44 0.50 5147.740 2.08 1.62 1.62 0.60 5147.84 2.74 1.77 1.77 100-year 0.70 5147.94 3.45 1.91 1.91 0.80 5148.04 4.21 2.04 2.04 0.90 5148.14 5.03 2.17 2.17 1.00 5148.240 5.89 2.28 2.28 Inlet at Design Point A4 is designed to intercept the full 100-yr flow of 1.83cfs at the elevation 5147.88 0.00 1.00 2.00 3.00 4.00 5.00 6.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 Discharge (cfs) Stage (ft) Stage - Discharge Curves Weir Flow Area Inlet Performance Curve: Design Point A7 - Drain Basin 10-2 Governing Equations: At low flow depths, the inlet will act like a weir governed by the following equation: * where P = 2(L + W) * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of the inlet grate * where H corresponds to the depth of water above the centroid of the cross-sectional area (A) The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown. However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation will cross at a certain flow depth. The two curves can be found below: If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters: Type of Grate: 15" ADS Drop In Grate 1599CGD Shape Circular Length of Grate (ft): 1.25 Width of Grate (ft): 1.25 Open Area of Grate (ft 2 ): 0.85 Flowline Elevation (ft): 5147.050 Allowable Capacity: 50% Depth vs. Flow: Depth Above Inlet (ft) Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs) 0.00 5147.05 0.00 0.00 0.00 0.03 5147.08 0.03 0.40 0.03 0.06 5147.11 0.09 0.56 0.09 0.09 5147.14 0.16 0.69 0.16 0.12 5147.17 0.24 0.79 0.24 0.15 5147.200 0.34 0.88 0.34 0.18 5147.23 0.45 0.97 0.45 Q2 0.21 5147.26 0.57 1.05 0.57 0.24 5147.29 0.69 1.12 0.69 0.27 5147.32 0.83 1.19 0.83 0.30 5147.350 0.97 1.25 0.97 Inlet at Design Point A7 is designed to intercept the full 2-yr flow of 0.45 cfs at the elevation 5147.23 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 0.00 0.05 0.10 0.15 0.20 0.25 0.30 Discharge (cfs) Stage (ft) Stage - Discharge Curves Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK = 0.0 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) nBACK = 0.012 Height of Curb at Gutter Flow Line HCURB = 6.00 inches Distance from Curb Face to Street Crown TCROWN = 40.0 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) nSTREET = 0.012 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX = 16.5 18.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 6.0 inches Check boxes are not applicable in SUMP conditions MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow = SUMP SUMP cfs Version 4.05 Released March 2017 ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Mountain's Edge DP B1 - INLET 7-1 Basin B - Inlets.xlsm, DP B1 - INLET 7-1 2/17/2018, 3:45 PM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a' from above) alocal = 2.00 2.00 inches Number of Unit Inlets (Grate or Curb Opening) No = 2 2 Water Depth at Flowline (outside of local depression) Ponding Depth = 5.5 5.8 inches Grate Information MINOR MAJOR Length of a Unit Grate Lo (G) = 3.00 3.00 feet Width of a Unit Grate Wo = 1.73 1.73 feet Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio = 0.43 0.43 Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf (G) = 0.50 0.50 Grate Weir Coefficient (typical value 2.15 - 3.60) Cw (G) = 3.30 3.30 Grate Orifice Coefficient (typical value 0.60 - 0.80) Co (G) = 0.60 0.60 Curb Opening Information MINOR MAJOR Length of a Unit Curb Opening Lo (C) = 3.00 3.00 feet Height of Vertical Curb Opening in Inches Hvert = 6.50 6.50 inches Height of Curb Orifice Throat in Inches Hthroat = 5.25 5.25 inches Angle of Throat (see USDCM Figure ST-5) 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) Cf (C) = 0.10 0.10 Curb Opening Weir Coefficient (typical value 2.3-3.7) Cw (C) = 3.70 3.70 Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co (C) = 0.66 0.66 Low Head Performance Reduction (Calculated) MINOR MAJOR Depth for Grate Midwidth dGrate = 0.479 0.509 ft Depth for Curb Opening Weir Equation dCurb = 0.29 0.32 ft Combination Inlet Performance Reduction Factor for Long Inlets RFCombination = 0.64 0.69 Curb Opening Performance Reduction Factor for Long Inlets RFCurb = 1.00 1.00 Grated Inlet Performance Reduction Factor for Long Inlets RFGrate = 0.64 0.69 MINOR MAJOR Total Inlet Interception Capacity (assumes clogged condition) Qa = 4.1 4.9 cfs Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK) Q PEAK REQUIRED = 1.1 4.1 cfs CDOT/Denver 13 Combination INLET IN A SUMP OR SAG LOCATION Version 4.05 Released March 2017 H-Vert H-Curb W Lo (C) Lo (G) Wo WP CDOT/Denver 13 Combination Override Depths Basin B - Inlets.xlsm, DP B1 - INLET 7-1 2/17/2018, 3:45 PM Area Inlet Performance Curve: Mountain's Edge - Design Point B2/Inlet 6-4 Governing Equations: At low flow depths, the inlet will act like a weir governed by the following equation: * where P = 2(L + W) * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of the inlet grate * where H corresponds to the depth of water above the centroid of the cross-sectional area (A) The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown. However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation will cross at a certain flow depth. The two curves can be found below: If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters: Type of Grate: CDOT Type C Close Mesh Grate Shape Rectangular Length of Grate (ft): 3.33 Width of Grate (ft): 2.75 Open Area of Grate (ft 2 ): 7.54 Flowline Elevation (ft): 5140.600 Allowable Capacity: 50% Depth vs. Flow: Depth Above Inlet (ft) Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs) 0.00 5140.60 0.00 0.00 0.00 0.10 5140.70 0.58 6.41 0.58 0.20 5140.80 1.63 9.06 1.63 0.30 5140.90 3.00 11.10 3.00 0.40 5141.00 4.61 12.81 4.61 0.50 5141.100 6.45 14.33 6.45 0.60 5141.20 8.48 15.69 8.48 Q100 0.70 5141.30 10.68 16.95 10.68 0.80 5141.40 13.05 18.12 13.05 0.90 5141.50 15.57 19.22 15.57 1.00 5141.600 18.24 20.26 18.24 Inlet at Design Point B2 full 100-yr flow of 8.71 (B1 and B2) cfs at the elevation 0.61 above the inlet elevation. 0.00 5.00 10.00 15.00 20.00 25.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 Discharge (cfs) Stage (ft) Stage - Discharge Curves Weir Flow Orifice Flow Area Inlet Performance Curve: Mountain's Edge - Design Point B3/Inlet 6-4A Governing Equations: At low flow depths, the inlet will act like a weir governed by the following equation: * where P = 2(L + W) * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of the inlet grate * where H corresponds to the depth of water above the centroid of the cross-sectional area (A) The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown. However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation will cross at a certain flow depth. The two curves can be found below: If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters: Type of Grate: CDOT Type C Close Mesh Grate Shape Rectangular Length of Grate (ft): 3.33 Width of Grate (ft): 2.75 Open Area of Grate (ft 2 ): 7.54 Flowline Elevation (ft): 5143.500 Allowable Capacity: 50% Depth vs. Flow: Depth Above Inlet (ft) Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs) 0.00 5143.50 0.00 0.00 0.00 0.10 5143.60 0.58 6.41 0.58 0.20 5143.70 1.63 9.06 1.63 0.30 5143.80 3.00 11.10 3.00 0.40 5143.90 4.61 12.81 4.61 0.50 5144.000 6.45 14.33 6.45 0.60 5144.10 8.48 15.69 8.48 0.70 5144.20 10.68 16.95 10.68 0.80 5144.30 13.05 18.12 13.05 Q100 0.90 5144.40 15.57 19.22 15.57 1.00 5144.500 18.24 20.26 18.24 Inlet at Design Point B3 full 100-yr flow of 12.10 cfs at the elevation 0.76 above the inlet elevation. 0.00 5.00 10.00 15.00 20.00 25.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 Discharge (cfs) Stage (ft) Stage - Discharge Curves Weir Flow Orifice Flow Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK = 10.0 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) nBACK = 0.012 Height of Curb at Gutter Flow Line HCURB = 6.00 inches Distance from Curb Face to Street Crown TCROWN = 18.0 ft Gutter Width W = 2.00 ft Street Transverse Slope SX = 0.023 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 = 0.020 ft/ft Manning's Roughness for Street Section (typically between 0.012 and 0.020) nSTREET = 0.012 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX = 16.5 18.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 6.0 inches Allow Flow Depth at Street Crown (leave blank for no) check = yes MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow = 23.6 23.6 cfs Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management' Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management' Version 4.05 Released March 2017 ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Mountain's Edge DP B4 INLET 6-2 Basin B - Inlets.xlsm, DP B4 INLET 6-2 2/17/2018, 3:46 PM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a') aLOCAL = 2.0 2.0 inches Total Number of Units in the Inlet (Grate or Curb Opening) No = 1 1 Length of a Single Unit Inlet (Grate or Curb Opening) Lo = 3.00 3.00 ft Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo = 2.00 2.00 ft Clogging Factor for a Single Unit Grate (typical min. value = 0.5) Cf-G = 0.50 0.50 Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1) Cf-C = 0.10 0.10 Street Hydraulics: OK - Q < Allowable Street Capacity' MINOR MAJOR Total Inlet Interception Capacity Q = 0.1 0.5 cfs Total Inlet Carry-Over Flow (flow bypassing inlet) Qb = 0.0 0.0 cfs Capture Percentage = Qa/Q o = C% = 100 100 % INLET ON A CONTINUOUS GRADE Version 4.05 Released March 2017 User-Defined Combination User-Defined Combination Basin B - Inlets.xlsm, DP B4 INLET 6-2 2/17/2018, 3:46 PM Project: Inlet ID: Gutter Geometry (Enter data in the blue cells) Maximum Allowable Width for Spread Behind Curb TBACK = 10.0 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) nBACK = 0.012 Height of Curb at Gutter Flow Line HCURB = 4.75 inches Distance from Curb Face to Street Crown TCROWN = 18.0 ft Gutter Width W = 1.17 ft Street Transverse Slope SX = 0.230 ft/ft Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft) SW = 0.098 ft/ft Street Longitudinal Slope - Enter 0 for sump condition SO = 0.020 ft/ft Manning's Roughness for Street Section (typically between 0.012 and 0.020) nSTREET = 0.012 Minor Storm Major Storm Max. Allowable Spread for Minor & Major Storm TMAX = 18.0 18.0 ft Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 4.8 4.8 inches Allow Flow Depth at Street Crown (leave blank for no) check = yes MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow = 4.4 4.4 cfs Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management' Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management' Version 4.05 Released March 2017 ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm) (Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread) Mountain's Edge DP B5 INLET 6-1 Basin B - Inlets.xlsm, DP B5 INLET 6-1 2/17/2018, 3:46 PM Design Information (Input) MINOR MAJOR Type of Inlet Type = Local Depression (additional to continuous gutter depression 'a') aLOCAL = 2.0 2.0 inches Total Number of Units in the Inlet (Grate or Curb Opening) No = 2 2 Length of a Single Unit Inlet (Grate or Curb Opening) Lo = 3.00 3.00 ft Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo = 2.00 2.00 ft Clogging Factor for a Single Unit Grate (typical min. value = 0.5) Cf-G = 0.50 0.50 Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1) Cf-C = 0.10 0.10 Street Hydraulics: OK - Q < Allowable Street Capacity' MINOR MAJOR Total Inlet Interception Capacity Q = 0.4 1.8 cfs Total Inlet Carry-Over Flow (flow bypassing inlet) Qb = 0.0 0.0 cfs Capture Percentage = Qa/Q o = C% = 100 100 % INLET ON A CONTINUOUS GRADE Version 4.05 Released March 2017 User-Defined Combination User-Defined Combination Basin B - Inlets.xlsm, DP B5 INLET 6-1 2/17/2018, 3:46 PM Area Inlet Performance Curve: Mountain's Edge - Design Point C1/Inlet 4-1 Governing Equations: At low flow depths, the inlet will act like a weir governed by the following equation: * where P = 2(L + W) * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of the inlet grate * where H corresponds to the depth of water above the centroid of the cross-sectional area (A) The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown. However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation will cross at a certain flow depth. The two curves can be found below: If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters: Type of Grate: Neenah R-3409 Shape Rectangular Length of Grate (ft): 2.4 Width of Grate (ft): 1.4 Open Area of Grate (ft 2 ): 1.50 Flowline Elevation (ft): 5151.110 Allowable Capacity: 50% Depth vs. Flow: Depth Above Inlet (ft) Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs) 0.00 5151.11 0.00 0.00 0.00 0.05 5151.16 0.13 0.90 0.13 0.10 5151.21 0.36 1.27 0.36 0.15 5151.26 0.66 1.56 0.66 0.20 5151.31 1.02 1.80 1.02 Q100 0.25 5151.360 1.43 2.02 1.43 0.30 5151.41 1.87 2.21 1.87 0.35 5151.46 2.36 2.38 2.36 0.40 5151.51 2.88 2.55 2.55 0.45 5151.56 3.44 2.70 2.70 0.50 5151.610 4.03 2.85 2.85 Inlet at Design Point C1 is designed to intercept the full 100-yr flow of 1.08 cfs at the elevation 5151.32. 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 0.50 Discharge (cfs) Stage (ft) Area Inlet Performance Curve: Mountain's Edge - Design Point D2/Inlet 1-4 Governing Equations: At low flow depths, the inlet will act like a weir governed by the following equation: * where P = 2(L + W) * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of the inlet grate * where H corresponds to the depth of water above the centroid of the cross-sectional area (A) The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown. However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation will cross at a certain flow depth. The two curves can be found below: If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters: Type of Grate: CDOT Type C Close Mesh Grate Shape Rectangular Length of Grate (ft): 3.33 Width of Grate (ft): 2.75 Open Area of Grate (ft 2 ): 7.54 Flowline Elevation (ft): 5143.370 Allowable Capacity: 50% Depth vs. Flow: Depth Above Inlet (ft) Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs) 0.00 5143.37 0.00 0.00 0.00 0.10 5143.47 0.58 6.41 0.58 0.20 5143.57 1.63 9.06 1.63 0.30 5143.67 3.00 11.10 3.00 0.40 5143.77 4.61 12.81 4.61 0.50 5143.870 6.45 14.33 6.45 0.60 5143.97 8.48 15.69 8.48 0.70 5144.07 10.68 16.95 10.68 0.80 5144.17 13.05 18.12 13.05 0.90 5144.27 15.57 19.22 15.57 Q100 1.00 5144.370 18.24 20.26 18.24 Inlet at Design Point D2 full 100-yr flow of 17.15 cfs at the elevation 5144.33. 0.00 5.00 10.00 15.00 20.00 25.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 Discharge (cfs) Stage (ft) Stage - Discharge Curves Weir Flow Orifice Flow Area Inlet Performance Curve: Mountain's Edge - Design Point D3/Inlet 1-4C Governing Equations: At low flow depths, the inlet will act like a weir governed by the following equation: * where P = 2(L + W) * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of the inlet grate * where H corresponds to the depth of water above the centroid of the cross-sectional area (A) The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown. However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation will cross at a certain flow depth. The two curves can be found below: If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters: Type of Grate: CDOT Type C Close Mesh Grate Shape Rectangular Length of Grate (ft): 3.33 Width of Grate (ft): 2.75 Open Area of Grate (ft 2 ): 7.54 Flowline Elevation (ft): 5142.600 Allowable Capacity: 50% Depth vs. Flow: Depth Above Inlet (ft) Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs) 0.00 5142.60 0.00 0.00 0.00 0.10 5142.70 0.58 6.41 0.58 0.20 5142.80 1.63 9.06 1.63 0.30 5142.90 3.00 11.10 3.00 0.40 5143.00 4.61 12.81 4.61 0.50 5143.100 6.45 14.33 6.45 0.60 5143.20 8.48 15.69 8.48 Q100 0.70 5143.30 10.68 16.95 10.68 0.80 5143.40 13.05 18.12 13.05 0.90 5143.50 15.57 19.22 15.57 1.00 5143.600 18.24 20.26 18.24 Inlet at Design Point D3 full 100-yr flow of 8.22 cfs at the elevation 5143.19. 0.00 5.00 10.00 15.00 20.00 25.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 Discharge (cfs) Stage (ft) Stage - Discharge Curves Weir Flow Orifice Flow Area Inlet Performance Curve: Mountain's Edge - Design Point D5/Outlet Structure 14-1 Governing Equations: At low flow depths, the inlet will act like a weir governed by the following equation: * where P = 2(L + W) * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of the inlet grate * where H corresponds to the depth of water above the centroid of the cross-sectional area (A) The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown. However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation will cross at a certain flow depth. The two curves can be found below: If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters: Type of Grate: Rain Garden Outlet Grate (3 Grates) Shape Rectangular Length of Grate (ft): 5.75 Width of Grate (ft): 1.75 Open Area of Grate (ft 2 ): 9.00 Flowline Elevation (ft): 5140.650 Allowable Capacity: 75% Depth vs. Flow: Depth Above Inlet (ft) Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs) 0.00 5140.65 0.00 0.00 0.00 0.15 5140.80 1.96 14.05 1.96 0.30 5140.95 5.55 19.87 5.55 0.45 5141.10 10.19 24.33 10.19 0.60 5141.25 15.69 28.10 15.69 0.75 5141.400 21.92 31.42 21.92 0.90 5141.55 28.82 34.41 28.82 1.05 5141.70 36.31 37.17 36.31 Q100 1.20 5141.85 44.37 39.74 39.74 1.35 5142.00 52.94 42.15 42.15 1.50 5142.150 62.00 44.43 44.43 Inlet at Design Point D5 full 100-yr flow of 36.35 cfs at the elevation 5141.70 0.00 10.00 20.00 30.00 40.00 50.00 60.00 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Discharge (cfs) Stage (ft) Stage - Discharge Curves Weir Flow APPENDIX B.5 OVERTOPPING ANALYSIS HY-8 Culvert Analysis Report Project Notes Project Title: Designer: Project Date:Wednesday, February 07, 2018 Notes: Project Units: U.S. Customary Units Outlet Control Option: Profiles Exit Loss Option: Standard Method Crossing Notes: Crossing Discharge Data Discharge Selection Method: Specify Minimum, Design, and Maximum Flow Minimum Flow: 19.49 cfs Design Flow: 19.49 cfs Maximum Flow: 19.49 cfs Table 1 - Summary of Culvert Flows at Crossing: Storm 10 Overtopping Headwater Elevation (ft) Total Discharge (cfs) Culvert 2 Discharge (cfs) Roadway Discharge (cfs) Iterations 47.94 19.49 12.36 7.10 7 47.94 19.49 12.36 7.10 2 47.94 19.49 12.36 7.10 2 47.94 19.49 12.36 7.10 2 47.94 19.49 12.36 7.10 2 47.94 19.49 12.36 7.10 2 47.94 19.49 12.36 7.10 2 47.94 19.49 12.36 7.10 2 47.94 19.49 12.36 7.10 2 47.94 19.49 12.36 7.10 2 47.94 19.49 12.36 7.10 2 47.50 10.87 10.87 0.00 Overtopping Crossing Front View (Roadway Profile): Storm 10 Overtopping Culvert Notes: Culvert 2 Table 2 - Culvert Summary Table: Culvert 2 Total Discharge (cfs) Culvert Discharge (cfs) Headwater Elevation (ft) Inlet Control Depth (ft) Outlet Control Depth (ft) Flow Type Normal Depth (ft) Critical Depth (ft) Outlet Depth (ft) Tailwater Depth (ft) Outlet Velocity (ft/s) Tailwater Velocity (ft/s) 19.49 12.36 47.94 2.939 2.641 9-JA2c -1.000 1.327 1.327 1.107 7.491 3.522 19.49 12.36 47.94 2.939 2.641 9-JA2c -1.000 1.327 1.327 1.107 7.491 3.522 19.49 12.36 47.94 2.939 2.641 9-JA2c -1.000 1.327 1.327 1.107 7.491 3.522 19.49 12.36 47.94 2.939 2.641 9-JA2c -1.000 1.327 1.327 1.107 7.491 3.522 19.49 12.36 47.94 2.939 2.641 9-JA2c -1.000 1.327 1.327 1.107 7.491 3.522 19.49 12.36 47.94 2.939 2.641 9-JA2c -1.000 1.327 1.327 1.107 7.491 3.522 19.49 12.36 47.94 2.939 2.641 9-JA2c -1.000 1.327 1.327 1.107 7.491 3.522 19.49 12.36 47.94 2.939 2.641 9-JA2c -1.000 1.327 1.327 1.107 7.491 3.522 19.49 12.36 47.94 2.939 2.641 9-JA2c -1.000 1.327 1.327 1.107 7.491 3.522 19.49 12.36 47.94 2.939 2.641 9-JA2c -1.000 1.327 1.327 1.107 7.491 3.522 19.49 12.36 47.94 2.939 2.641 9-JA2c -1.000 1.327 1.327 1.107 7.491 3.522 Water Surface Profile Plot for Culvert: Culvert 2 Site Data - Culvert 2 Site Data Option: Culvert Invert Data Inlet Station: 0.00 ft Inlet Elevation: 45.00 ft Outlet Station: 62.00 ft Outlet Elevation: 45.30 ft Number of Barrels: 1 Culvert Data Summary - Culvert 2 Barrel Shape: Circular Barrel Diameter: 1.50 ft Barrel Material: Concrete Embedment: 0.00 in Barrel Manning's n: 0.0120 Culvert Type: Straight Inlet Configuration: Square Edge with Headwall Inlet Depression: NONE Table 3 - Downstream Channel Rating Curve (Crossing: Storm 10 Overtopping) Flow (cfs) Water Surface Elev (ft) Depth (ft) Velocity (ft/s) Shear (psf) Froude Number 19.49 46.41 1.11 3.52 0.35 0.59 19.49 46.41 1.11 3.52 0.35 0.59 19.49 46.41 1.11 3.52 0.35 0.59 19.49 46.41 1.11 3.52 0.35 0.59 19.49 46.41 1.11 3.52 0.35 0.59 19.49 46.41 1.11 3.52 0.35 0.59 19.49 46.41 1.11 3.52 0.35 0.59 19.49 46.41 1.11 3.52 0.35 0.59 19.49 46.41 1.11 3.52 0.35 0.59 19.49 46.41 1.11 3.52 0.35 0.59 19.49 46.41 1.11 3.52 0.35 0.59 APPENDIX B.6 OVERFLOW WEIRS Weir Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Saturday, Feb 17 2018 Detention Pond 4 Emergency Overflow Weir Trapezoidal Weir Crest = Sharp Bottom Length (ft) = 20.00 Total Depth (ft) = 0.50 Side Slope (z:1) = 4.00 Calculations Weir Coeff. Cw = 3.10 Compute by: Q vs Depth No. Increments = 38 Highlighted Depth (ft) = 0.50 Q (cfs) = 23.67 Area (sqft) = 11.00 Velocity (ft/s) = 2.15 Top Width (ft) = 24.00 0 5 10 15 20 25 30 35 Depth (ft) Detention Pond 4 Emergency Overflow Weir Depth (ft) -0.50 -0.50 0.00 0.00 0.50 0.50 1.00 1.00 Length (ft) Weir W.S. Weir Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Friday, Feb 16 2018 Rain Garden 1 100-yr Overflow Trapezoidal Weir Crest = Sharp Bottom Length (ft) = 11.00 Total Depth (ft) = 0.50 Side Slope (z:1) = 4.00 Calculations Weir Coeff. Cw = 3.10 Compute by: Known Q Known Q (cfs) = 13.25 Highlighted Depth (ft) = 0.49 Q (cfs) = 13.25 Area (sqft) = 6.35 Velocity (ft/s) = 2.09 Top Width (ft) = 14.92 0 2 4 6 8 10 12 14 16 18 20 Depth (ft) Rain Garden 1 100-yr Overflow Depth (ft) -0.50 -0.50 0.00 0.00 0.50 0.50 1.00 1.00 Length (ft) Weir W.S. APPENDIX B.7 EROSION CONTROL MAT CALCULATIONS Project: 911-007 Date: February 14, 2018 Calculation by: SJT Storm Line Pipe Diameter (in) Velocity (cfs) Transition Mat W x L 1 30 6.59 8'x12' 2 15 3.82 4'x4' 3 15 1.65 4'x4' 4 15 3.10 4'x4' 5 24 5.91 8'x8' 6 24 7.73 8'x8' 7 18 4.46 8'x8' 8 18 12.45 8'x12' 9 12 4.49 4'x4' 10 18 7.49 8'x8' 11 10 4.69 4'x4' 12 12 4.00 4'x4' 14 30 7.96 8'x12' Scourstop Schedule CALCULATIONS FOR SCOURSTOP PROTECTION AT PIPE OUTLETS ScourStop® DESIGN GUIDE Circular Culvert Outlet Protection scourstop.com PERFORMANCE AESTHETICS NPDES-COMPLIANT COST-EFFECTIVE the green solution to riprap ® ScourStop transition mats protect against erosion and scour at culvert outlets with a vegetated solution in areas traditionally protected with rock or other hard armor. ScourStop is part of a system that includes semi-rigid transition mats installed over sod or turf reinforcement mats. Each 4’ x 4’ x 1/2” mat is made of high-density polyethylene and secured tightly to the ground with anchors. why use the SCOURSTOP SYSTEM? - If velocity is greater than 16 fps, contact manufacturer for design assistance. - ScourStop mats have been shown to at least double the effectiveness of turf reinforcement mats. - ScourStop fully vegetated channel (2:1 slope): velocity = 31 fps, shear stress = 16 psf. PIPE DIAMETER VELOCITY < 10 FT/SEC 10 < VELOCITY < 16 FT/SEC TRANSITION MAT W x L QUANTITY OF MATS TRANSITION MAT W x L QUANTITY OF MATS 12” 4’ x 4’ 1 4’ x 8’ 2 24” 8’ x 8’ 4 8’ x 12’ 6 36” 8’ x 12’ 6 12’ x 20’ 15 48” 12’ x 16’ 12 12’ x 24’ 18 60” 12’ x 20’ 15 16’ x 32’ 32 72” 16’ x 24’ 24 20’ x 36’ 45 Circular Culvert Outlet Protection These are minimum recommendations. More ScourStop protection may be needed depending upon site and soil conditions, per project engineer. 1. ScourStop mats must be installed over a soil cover: sod, seeded turf reinforcement mat (TRM), geotextile, or a combination thereof. 2. For steep slopes (>10%) or higher velocities (>10 ft/sec), sod is the recommended soil cover. 3. Follow manufacturer’s ScourStop Installation Guidelines to ensure proper installation. 4. Install ScourStop mats at maximum 1-2” below flowline of culvert or culvert apron. (No waterfall impacts onto ScourStop mats.) 5. Performance of protected area assumes stable downstream conditions. Transition mat apron protects culvert outlet. *Width of protection: Bottom width of channel and up both side slopes to a depth at least half the culvert diameter. Protect bare/disturbed downstream soils from erosion with appropriate soil cover. Use normal-depth calculator to compute for downstream protection. Install anchors per ScourStop Installation Guidelines. Minimum depth 24” in compacted, cohesive soil. Minimum depth 30” in loose, sandy, or wet soil. Extra anchors as needed to secure mat tightly over soil cover. Abut transition mats to end of culvert or culvert apron. Adjacent mats abut together laterally and longitudinally. Minimum 8 anchors per mat. Extra anchors as needed for loose or wet soils. Extra anchors as needed for uneven soil surface. ScourStop® Installation Recommendations A A MAX. 1"-2" DROP FROM CULVERT FLOWLINE CULVERT FLOWLINE ONTO SCOURSTOP MATS PROFILE VIEW A LEADER in the GEOSYNTHETIC and EROSION CONTROL industries Learn more about our products at: HanesGeo.com | 888.239.4539 the green solution to riprap ©2014 Leggett & Platt, Incorporated | 16959_1114 AA APPENDIX C EROSION CONTROL REPORT Mountain’s Edge Preliminary Erosion Control Report A comprehensive Erosion and Sediment Control Plan (along with associated details) will be included with the final construction drawings. It should be noted, however, that any such Erosion and Sediment Control Plan serves only as a general guide to the Contractor. Staging and/or phasing of the BMPs depicted, and additional or different BMPs from those included may be necessary during construction, or as required by the authorities having jurisdiction. It shall be the responsibility of the Contractor to ensure erosion control measures are properly maintained and followed. The Erosion and Sediment Control Plan is intended to be a living document, constantly adapting to site conditions and needs. The Contractor shall update the location of BMPs as they are installed, removed or modified in conjunction with construction activities. It is imperative to appropriately reflect the current site conditions at all times. The Erosion and Sediment Control Plan shall address both temporary measures to be implemented during construction, as well as permanent erosion control protection. Best Management Practices from the Volume 3, Chapter 7 – Construction BMPs will be utilized. Measures may include, but are not limited to, silt fencing along the disturbed perimeter, gutter protection in the adjacent roadways and inlet protection at existing and proposed storm inlets. Vehicle tracking control pads, spill containment and clean-up procedures, designated concrete washout areas, dumpsters, and job site restrooms shall also be provided by the Contractor. Grading and Erosion Control Notes can be found on Sheet CS2 of the Utility Plans. The Utility Plans at final design will also contain a full-size Erosion Control Plan as well as a separate sheet dedicated to Erosion Control Details. In addition to this report and the referenced plan sheets, the Contractor shall be aware of, and adhere to, the applicable requirements outlined in any existing Development Agreement(s) of record, as well as the Development Agreement, to be recorded prior to issuance of the Development Construction Permit. Also, the Site Contractor for this project will be required to secure a Stormwater Construction General Permit from the Colorado Department of Public Health and Environment (CDPHE), Water Quality Control Division – Stormwater Program, before commencing any earth disturbing activities. Prior to securing said permit, the Site Contractor shall develop a comprehensive StormWater Management Plan (SWMP) pursuant to CDPHE requirements and guidelines. The SWMP will further describe and document the ongoing activities, inspections, and maintenance of construction BMPs. APPENDIX D LID EXHIBIT Project: Mountain's Edge Calculations By: S. Thomas Date: February 17, 2018 LID BASIN NODE Sub-Basin(s) Area, A (sf) Percent Impervious Impervious Area, A (sf) LID Treatment L1 A1 63,123 65% 41,335 Total L1 63,123 65% 41,335 L2 D1 10,927 99% 10,871 D2 72,144 62% 44,888 D3 38,358 68% 26,248 D4 28,254 61% 17,175 D5 38,620 22% 8,635 Total L2 188,303 57% 107,817 Total Treated 251,426 59% 149,152 LID BASIN NODE Sub-Basin(s) Area, A (sf) Percent Impervious Impervious Area, A (sf) A2 11,641 43% 5,051 A3 10,068 41% 4,149 A4 11,096 42% 4,679 A5 49,551 84% 41,724 A6 15,003 55% 8,211 A7 17,678 39% 6,916 A8 66,983 21% 14,066 B1 18,143 99% 18,010 B2 26,995 44% 11,906 B3 52,955 77% 40,698 B4 2,534 66% 1,662 B5 8,132 74% 6,013 B6 17,641 33% 5,806 B7 47,481 7% 3,399 C1 6,746 40% 2,715 C2 20,976 17% 3,648 D6 24,840 18% 4,500 UD1 2,263 80% 1,810 Total Proposed Untreated 410,726 45% 184,963 B1 18,143 99% 18,010 D1 10,927 99% 10,871 3,819 90% 3,437 Total Overland Trail ROW 32,889 98% 32,318 PROPOSED LID COMPUTATIONS PROPOSED LID UNTREATED AREA PROPOSED LID TREATED AREA Rain Garden 2 Project: Mountain's Edge Calculations By: S. Thomas Date: February 17, 2018 PROPOSED LID COMPUTATIONS 662,152 32,318 334,115 301,796 150,898 149,152 49.4% Rain Garden 1 Rain Garden 2 Total Contributing Area (sf) 63,123 188,303 Percent Impervious 65% 57% Total Volume Required (cf) 1,086 2,843 Total Volume Provided (cf) 1,255 3,154 LID TREATMENT SUMMARY Total Site Area (sf) Total Net Proposed Impervious Area (sf) RAIN GARDEN SUMMARY Total Overland ROW Impervious Area not required to be treated (sf) (Basins B1, D1) Total Proposed Impervious Area (sf) Total Treated Impervious Area (sf) Percent Impervious Treated by LID measures 50% Required Minimum Area to be Treated by LID measures (sf) UD UD T AS PL O YL N UD C IT EL I R NO T S LA P LO Y N D CU T I L E RI O N ST A PL O YL N UD C IT EL RI O N T AS L OP L Y N D U TC LI E I R O N T AS APPENDIX E SWMM Modeling SUB-A SUB-B SUB-C SUB-D HT OS1 OS2 SUB-UD2 1 2 3 8 9 10 11 BYPASS POND2OVERFLOW POND4OVERFLOW OUT1 OUT2 OUT3 OUT4 OUTOS1 OUTOS2 J1 J2 J3 J4 J5 J6 J7 O1 O2 O3 POND1 POND2 POND3 POND4 PONDOS1 PONDOS2 FORTCOLLINS 03/15/2016 00:05:00 SWMM 5.1 Page 1 Mountains Edge - SWMM 100yr.inp [TITLE] ;;Project Title/Notes [OPTIONS] ;;Option Value FLOW_UNITS CFS INFILTRATION HORTON FLOW_ROUTING KINWAVE LINK_OFFSETS DEPTH MIN_SLOPE 0 ALLOW_PONDING NO SKIP_STEADY_STATE NO START_DATE 03/15/2016 START_TIME 00:00:00 REPORT_START_DATE 03/15/2016 REPORT_START_TIME 00:00:00 END_DATE 03/20/2016 END_TIME 06:00:00 SWEEP_START 01/01 SWEEP_END 12/31 DRY_DAYS 0 REPORT_STEP 00:05:00 WET_STEP 00:05:00 DRY_STEP 01:00:00 ROUTING_STEP 0:00:15 INERTIAL_DAMPING PARTIAL NORMAL_FLOW_LIMITED BOTH FORCE_MAIN_EQUATION H-W VARIABLE_STEP 0.75 LENGTHENING_STEP 0 MIN_SURFAREA 12.557 MAX_TRIALS 8 HEAD_TOLERANCE 0.005 SYS_FLOW_TOL 5 LAT_FLOW_TOL 5 MINIMUM_STEP 0.5 THREADS 1 [EVAPORATION] ;;Data Source Parameters ;;-------------- ---------------- CONSTANT 0.0 DRY_ONLY NO Page 1 Mountains Edge - SWMM 100yr.inp [RAINGAGES] ;;Name Format Interval SCF Source ;;-------------- --------- ------ ------ ---------- FORTCOLLINS INTENSITY 0:05 1.0 TIMESERIES 100-YR [SUBCATCHMENTS] ;;Name Rain Gage Outlet Area %Imperv Width %Slope CurbLen SnowPack ;;-------------- ---------------- ---------------- -------- -------- -------- -------- -------- ---------------- SUB-A FORTCOLLINS POND1 5.77 50 551 2 0 SUB-B FORTCOLLINS POND2 3.99 50 226 2 0 SUB-C FORTCOLLINS POND3 .64 23 219 2 0 SUB-D FORTCOLLINS POND4 4.89 53 447 2 0 HT FORTCOLLINS J4 5.51 3 750 2 0 OS1 FORTCOLLINS PONDOS1 14.72 10 1000 2 0 OS2 FORTCOLLINS PONDOS2 63.62 10 3000 2 0 SUB-UD2 FORTCOLLINS J2 4.05 2 400 5 0 [SUBAREAS] ;;Subcatchment N-Imperv N-Perv S-Imperv S-Perv PctZero RouteTo PctRouted ;;-------------- ---------- ---------- ---------- ---------- ---------- ---------- ---------- SUB-A .016 .25 .1 .3 0 OUTLET SUB-B .016 .25 .1 .3 0 OUTLET SUB-C .016 .25 .1 .3 0 OUTLET SUB-D .016 .25 .1 .3 0 OUTLET HT .016 .25 .1 .3 0 OUTLET OS1 .016 .25 .1 .3 0 OUTLET OS2 .016 .25 .1 .3 0 OUTLET SUB-UD2 .016 .25 .1 .3 0 OUTLET [INFILTRATION] ;;Subcatchment MaxRate MinRate Decay DryTime MaxInfil ;;-------------- ---------- ---------- ---------- ---------- ---------- SUB-A .51 0.5 .0018 7 0 SUB-B .51 0.5 .0018 7 0 SUB-C .51 0.5 .0018 7 0 SUB-D .51 0.5 6.48 7 0 HT 3.0 0.5 4 7 0 OS1 3.0 0.5 4 7 0 OS2 3.0 0.5 4 7 0 SUB-UD2 3.0 0.5 4 7 0 [JUNCTIONS] ;;Name Elevation MaxDepth InitDepth SurDepth Aponded ;;-------------- ---------- ---------- ---------- ---------- ---------- J1 40.7 5 0 0 0 J2 39.1 5 0 0 0 Page 2 Mountains Edge - SWMM 100yr.inp J3 34.2 5 0 0 0 J4 38.22 3 0 0 0 J5 45.6 3 0 0 0 J6 36.5 2 0 0 0 J7 35 2 0 0 0 [OUTFALLS] ;;Name Elevation Type Stage Data Gated Route To ;;-------------- ---------- ---------- ---------------- -------- ---------------- O1 35.5 FREE NO O2 33.6 FREE NO O3 48 FREE NO [STORAGE] ;;Name Elev. MaxDepth InitDepth Shape Curve Name/Params N/A Fevap Psi Ksat IMD ;;-------------- -------- ---------- ----------- ---------- ---------------------------- -------- -------- -------- -------- POND1 40 5.2 1.8 TABULAR POND1 0 0 POND2 37 3 1 TABULAR POND2 0 0 POND3 42 3.6 1 TABULAR POND3 0 0 POND4 36.6 7.5 1.06 TABULAR POND4 0 0 PONDOS1 47 7 0 TABULAR PONDOS1 0 0 PONDOS2 44 7 0 TABULAR PONDOS2 0 0 [CONDUITS] ;;Name From Node To Node Length Roughness InOffset OutOffset InitFlow MaxFlow ;;-------------- ---------------- ---------------- ---------- ---------- ---------- ---------- ---------- ---------- 1 J1 J2 300 .025 0 0 0 0 2 J2 J3 300 .025 0 0 0 0 3 J3 O2 100 .025 0 0 0 0 8 J5 J4 400 .025 0 0 0 0 9 J4 O1 155 .025 0 0 0 0 10 J6 J7 600 .012 0 0 0 0 11 J7 J3 20 .012 0 0 0 0 [WEIRS] ;;Name From Node To Node Type CrestHt Qcoeff Gated EndCon EndCoeff Surcharge RoadWidth RoadSurf ;;-------------- ---------------- ---------------- ------------ ---------- ---------- -------- -------- ---------- ---------- ---------- ---------- BYPASS PONDOS2 O3 TRANSVERSE 6 3.33 NO 0 0 YES POND2OVERFLOW POND2 J6 TRANSVERSE 2.88 3.33 NO 0 0 YES POND4OVERFLOW POND4 J3 TRANSVERSE 7 3.33 NO 0 0 YES [OUTLETS] ;;Name From Node To Node Offset Type QTable/Qcoeff Qexpon Gated ;;-------------- ---------------- ---------------- ---------- --------------- ---------------- ---------- -------- Page 3 Mountains Edge - SWMM 100yr.inp OUT1 POND1 J6 0 TABULAR/DEPTH POND1ORIFICE NO OUT2 POND2 J6 0 TABULAR/DEPTH POND2ORIFICE NO OUT3 POND3 J1 0 TABULAR/DEPTH POND3ORIFICE NO OUT4 POND4 J7 0 TABULAR/DEPTH POND4ORIFICE NO OUTOS1 PONDOS1 J5 0 TABULAR/DEPTH PONDOS1ORIFICE NO OUTOS2 PONDOS2 J1 0 TABULAR/DEPTH PONDOS2ORIFICE NO [XSECTIONS] ;;Link Shape Geom1 Geom2 Geom3 Geom4 Barrels Culvert ;;-------------- ------------ ---------------- ---------- ---------- ---------- ---------- ---------- 1 TRIANGULAR 5 40 0 0 1 2 TRIANGULAR 5 40 0 0 1 3 TRIANGULAR 5 40 0 0 1 8 TRIANGULAR 1 24 0 0 1 9 TRIANGULAR 3 24 0 0 1 10 CIRCULAR 2 0 0 0 1 11 CIRCULAR 2 0 0 0 1 BYPASS RECT_OPEN 1 100 0 0 POND2OVERFLOW RECT_OPEN .5 8 0 0 POND4OVERFLOW RECT_OPEN .5 20 4 4 [CURVES] ;;Name Type X-Value Y-Value ;;-------------- ---------- ---------- ---------- POND1ORIFICE Rating 0 0 POND1ORIFICE 1.8 .04 POND1ORIFICE 5.2 .36 ; POND2ORIFICE Rating 0 0 POND2ORIFICE 1 .04 POND2ORIFICE 3 .43 ; POND3ORIFICE Rating 0 0 POND3ORIFICE 1 .01 POND3ORIFICE 3.8 .11 ; POND4ORIFICE Rating 0 0 POND4ORIFICE 1.06 .01 POND4ORIFICE 7.4 1.61 ; PONDOS1ORIFICE Rating 0.00 0.00 PONDOS1ORIFICE 0.50 11.76 PONDOS1ORIFICE 1.00 16.63 PONDOS1ORIFICE 1.50 20.37 PONDOS1ORIFICE 2.00 23.52 PONDOS1ORIFICE 2.50 26.30 Page 4 Mountains Edge - SWMM 100yr.inp PONDOS1ORIFICE 3.00 28.80 PONDOS1ORIFICE 3.50 31.11 PONDOS1ORIFICE 4.00 33.26 PONDOS1ORIFICE 4.50 35.28 PONDOS1ORIFICE 5.00 37.19 PONDOS1ORIFICE 5.50 39.00 PONDOS1ORIFICE 6.00 40.74 PONDOS1ORIFICE 6.50 42.40 PONDOS1ORIFICE 7.00 44.00 ; PONDOS2ORIFICE Rating 0.00 0.00 PONDOS2ORIFICE 0.50 6.35 PONDOS2ORIFICE 1.00 8.98 PONDOS2ORIFICE 1.50 11.00 PONDOS2ORIFICE 2.00 12.70 PONDOS2ORIFICE 2.50 14.20 PONDOS2ORIFICE 3.00 15.56 PONDOS2ORIFICE 3.50 16.80 PONDOS2ORIFICE 4.00 17.96 PONDOS2ORIFICE 4.50 19.05 PONDOS2ORIFICE 5.00 20.08 PONDOS2ORIFICE 5.50 21.06 PONDOS2ORIFICE 6.00 22.00 ; CLOGGEDORIFICE Rating 0 0 CLOGGEDORIFICE 8 0 ; POND1 Storage 0 55.92 POND1 0.2 247.88 POND1 0.4 558.27 POND1 0.6 990.51 POND1 0.8 1571.71 POND1 1 2313.58 POND1 1.2 3227.82 POND1 1.4 4344.24 POND1 1.6 5674.13 POND1 1.8 7190.63 POND1 2 8864.82 POND1 2.2 10468.85 POND1 2.4 11917.21 POND1 2.6 13190.51 POND1 2.8 14306.45 POND1 3 15372.19 POND1 3.2 16454.7 POND1 3.4 17573.05 POND1 3.6 18715.99 Page 5 Mountains Edge - SWMM 100yr.inp POND1 3.8 19883.17 POND1 4 20809.89 POND1 4.2 21611.7 POND1 4.4 22320.36 POND1 4.6 23022.24 POND1 4.8 23738.83 POND1 5 24470.01 POND1 5.2 25216.67 ; POND2 Storage 0 238.28 POND2 0.2 1613.88 POND2 0.4 4876.81 POND2 0.6 9378.79 POND2 0.8 13640.3 POND2 1 17021.31 POND2 1.2 18800.4 POND2 1.4 19490.52 POND2 1.6 19937.74 POND2 1.8 20399.03 POND2 2 20874.84 POND2 2.2 21369.74 POND2 2.4 21877.12 POND2 2.6 22434.96 POND2 2.8 23229.46 POND2 3 24094.17 POND2 3.2 24958.56 ; POND3 Storage 0 43.01 POND3 0.2 153.6 POND3 0.4 320.81 POND3 0.6 543.72 POND3 0.8 813.82 POND3 1 1113.57 POND3 1.2 1369.75 POND3 1.4 1525.17 POND3 1.6 1685.35 POND3 1.8 1850.34 POND3 2 2021.5 POND3 2.2 2199.22 POND3 2.4 2383.66 POND3 2.6 2575 POND3 2.8 2773.27 POND3 3 2978.68 POND3 3.2 3191.45 POND3 3.4 3411.74 POND3 3.6 3642.42 Page 6 Mountains Edge - SWMM 100yr.inp ; POND4 Storage 0 137.62 POND4 0.2 452.33 POND4 0.4 874.74 POND4 0.6 1341.09 POND4 0.8 1778.34 POND4 1 2229.43 POND4 1.2 2714.15 POND4 1.4 3207.82 POND4 1.6 3418.61 POND4 1.8 3629.69 POND4 2 3846.27 POND4 2.2 4068.54 POND4 2.4 4296.79 POND4 2.6 4531.04 POND4 2.8 4771.27 POND4 3 5017.49 POND4 3.2 5269.7 POND4 3.4 5527.9 POND4 3.6 5792.07 POND4 3.8 6062.24 POND4 4 6338.4 POND4 4.2 6620.53 POND4 4.4 6908.62 POND4 4.6 7202.56 POND4 4.8 7501.93 POND4 5 11733.79 POND4 5.2 12401.37 POND4 5.4 13086.37 POND4 5.6 13781.42 POND4 5.8 14491.21 POND4 6 15216.09 POND4 6.2 15955.84 POND4 6.4 16711.64 POND4 6.6 17512.7 POND4 6.8 18425.22 POND4 7 19472.64 POND4 7.2 20654.46 POND4 7.5 20654 ; PONDOS1 Storage 0 7453.84 PONDOS1 1 17466.34 PONDOS1 2 28633.01 PONDOS1 3 47631.06 PONDOS1 4 69976.41 PONDOS1 5 92755.43 Page 7 Mountains Edge - SWMM 100yr.inp PONDOS1 6 117217.13 PONDOS1 7 143723.75 ; PONDOS2 Storage 0 2031.79 PONDOS2 1 9775.88 PONDOS2 2 17701.44 PONDOS2 3 25195.74 PONDOS2 4 30910.42 PONDOS2 5 36766.41 PONDOS2 6 41957.84 PONDOS2 7 41957 [TIMESERIES] ;;Name Date Time Value ;;-------------- ---------- ---------- ---------- 100-YR 0:05 1 100-YR 0:10 1.14 100-YR 0:15 1.33 100-YR 0:20 2.23 100-YR 0:25 2.84 100-YR 0:30 5.49 100-YR 0:35 9.95 100-YR 0:40 4.12 100-YR 0:45 2.48 100-YR 0:50 1.46 100-YR 0:55 1.22 100-YR 1:00 1.06 100-YR 1:05 1 100-YR 1:10 .95 100-YR 1:15 .91 100-YR 1:20 .87 100-YR 1:25 .84 100-YR 1:30 .81 100-YR 1:35 .78 100-YR 1:40 .75 100-YR 1:45 .73 100-YR 1:50 .71 100-YR 1:55 .69 100-YR 2:00 .67 ; 5-YR 0:05 0.4 5-YR 0:10 0.45 5-YR 0:15 0.53 5-YR 0:20 0.89 5-YR 0:25 1.13 5-YR 0:30 2.19 Page 8 Mountains Edge - SWMM 100yr.inp 5-YR 0:35 3.97 5-YR 0:40 1.64 5-YR 0:45 0.99 5-YR 0:50 0.58 5-YR 0:55 0.49 5-YR 1:00 0.42 5-YR 1:05 0.28 5-YR 1:10 0.27 5-YR 1:15 0.25 5-YR 1:20 0.24 5-YR 1:25 0.23 5-YR 1:30 0.22 5-YR 1:35 0.21 5-YR 1:40 0.2 5-YR 1:45 0.19 5-YR 1:50 0.19 5-YR 1:55 0.18 5-YR 2:00 0.18 ; 10-YR 0:05 0.49 10-YR 0:10 0.56 10-YR 0:15 0.65 10-YR 0:20 1.09 10-YR 0:25 1.39 10-YR 0:30 2.69 10-YR 0:35 4.87 10-YR 0:40 2.02 10-YR 0:45 1.21 10-YR 0:50 0.71 10-YR 0:55 0.6 10-YR 1:00 0.52 10-YR 1:05 0.39 10-YR 1:10 0.37 10-YR 1:15 0.35 10-YR 1:20 0.34 10-YR 1:25 0.32 10-YR 1:30 0.31 10-YR 1:35 0.3 10-YR 1:40 0.29 10-YR 1:45 0.28 10-YR 1:50 0.27 10-YR 1:55 0.26 10-YR 2:00 0.25 ; 50-YR 0:05 0.79 50-YR 0:10 0.9 Page 9 Mountains Edge - SWMM 100yr.inp 50-YR 0:15 1.05 50-YR 0:20 1.77 50-YR 0:25 2.25 50-YR 0:30 4.36 50-YR 0:35 7.9 50-YR 0:40 3.27 50-YR 0:45 1.97 50-YR 0:50 1.16 50-YR 0:55 0.97 50-YR 1:00 0.84 50-YR 1:05 0.79 50-YR 1:10 0.75 50-YR 1:15 0.72 50-YR 1:20 0.69 50-YR 1:25 0.66 50-YR 1:30 0.64 50-YR 1:35 0.62 50-YR 1:40 0.6 50-YR 1:45 0.58 50-YR 1:50 0.56 50-YR 1:55 0.54 50-YR 2:00 0.53 ; 2-YR 0:05 .29 2-YR 0:10 .33 2-YR 0:15 .38 2-YR 0:20 .64 2-YR 0:25 .81 2-YR 0:30 1.57 2-YR 0:35 2.85 2-YR 0:40 1.18 2-YR 0:45 .71 2-YR 0:50 .42 2-YR 0:55 .35 2-YR 1:00 .3 2-YR 1:05 .2 2-YR 1:10 .19 2-YR 1:15 .18 2-YR 1:20 .17 2-YR 1:25 .17 2-YR 1:30 .16 2-YR 1:35 .15 2-YR 1:40 .15 2-YR 1:45 .14 2-YR 1:50 .14 2-YR 1:55 .13 Page 10 Mountains Edge - SWMM 100yr.inp 2-YR 2:00 .13 ; 25-YR 0:05 .63 25-YR 0:10 .72 25-YR 0:15 .84 25-YR 0:20 1.41 25-YR 0:25 1.8 25-YR 0:30 3.48 25-YR 0:35 6.3 25-YR 0:40 2.61 25-YR 0:45 1.57 25-YR 0:50 .92 25-YR 0:55 .77 25-YR 1:00 .67 25-YR 1:05 .62 25-YR 1:10 .59 25-YR 1:15 .56 25-YR 1:20 .54 25-YR 1:25 .52 25-YR 1:30 .5 25-YR 1:35 .48 25-YR 1:40 .47 25-YR 1:45 .45 25-YR 1:50 .44 25-YR 1:55 .42 25-YR 2:00 .41 [REPORT] ;;Reporting Options INPUT NO CONTROLS NO SUBCATCHMENTS ALL NODES ALL LINKS ALL [TAGS] [MAP] DIMENSIONS -1395.210 0.000 11395.210 10000.000 Units None [COORDINATES] ;;Node X-Coord Y-Coord ;;-------------- ------------------ ------------------ J1 6161.677 3556.886 J2 6808.383 4191.617 Page 11 Mountains Edge - SWMM 100yr.inp J3 7658.683 5053.892 J4 -101.797 5508.982 J5 -53.893 2586.826 J6 3946.108 4886.228 J7 6652.695 4814.371 O1 -77.845 6502.994 O2 8532.934 5257.485 O3 8401.198 1976.048 POND1 3131.736 3700.599 POND2 1610.778 5257.485 POND3 4664.671 2802.395 POND4 6904.192 5305.389 PONDOS1 880.239 1892.215 PONDOS2 6089.820 2083.832 [VERTICES] ;;Link X-Coord Y-Coord ;;-------------- ------------------ ------------------ 9 -65.869 6383.234 BYPASS 6916.168 1940.120 POND2OVERFLOW 3167.665 5952.096 POND4OVERFLOW 7729.502 5982.357 [Polygons] ;;Subcatchment X-Coord Y-Coord ;;-------------- ------------------ ------------------ SUB-A 1862.275 3449.102 SUB-B 784.431 4407.186 SUB-C 3431.138 2754.491 SUB-D 4868.263 4047.904 HT -1000.000 3688.623 OS1 892.215 1161.676 OS2 6053.892 1197.605 SUB-UD2 7359.282 3952.096 [SYMBOLS] ;;Gage X-Coord Y-Coord ;;-------------- ------------------ ------------------ FORTCOLLINS 1335.329 9161.677 [BACKDROP] FILE "D:\Projects\911-007\Drainage\SWMM\911-007_DRNG DR1 (1).jpg" DIMENSIONS -1395.210 1334.229 11395.210 8665.771 Page 12 SWMM - Developed 100-yr.rpt EPA STORM WATER MANAGEMENT MODEL - VERSION 5.1 (Build 5.1.012) -------------------------------------------------------------- ********************************************************* NOTE: The summary statistics displayed in this report are based on results found at every computational time step, not just on results from each reporting time step. ********************************************************* **************** Analysis Options **************** Flow Units ............... CFS Process Models: Rainfall/Runoff ........ YES RDII ................... NO Snowmelt ............... NO Groundwater ............ NO Flow Routing ........... YES Ponding Allowed ........ NO Water Quality .......... NO Infiltration Method ...... HORTON Flow Routing Method ...... KINWAVE Starting Date ............ 03/15/2016 00:00:00 Ending Date .............. 03/20/2016 06:00:00 Antecedent Dry Days ...... 0.0 Report Time Step ......... 00:05:00 Wet Time Step ............ 00:05:00 Dry Time Step ............ 01:00:00 Routing Time Step ........ 15.00 sec ************************** Volume Depth Runoff Quantity Continuity acre-feet inches ************************** --------- ------- Total Precipitation ...... 31.552 3.669 Evaporation Loss ......... 0.000 0.000 Infiltration Loss ........ 17.014 1.979 Surface Runoff ........... 14.493 1.685 Final Storage ............ 0.131 0.015 Continuity Error (%) ..... -0.274 Page 1 SWMM - Developed 100-yr.rpt ************************** Volume Volume Flow Routing Continuity acre-feet 10^6 gal ************************** --------- --------- Dry Weather Inflow ....... 0.000 0.000 Wet Weather Inflow ....... 14.493 4.723 Groundwater Inflow ....... 0.000 0.000 RDII Inflow .............. 0.000 0.000 External Inflow .......... 0.000 0.000 External Outflow ......... 14.760 4.810 Flooding Loss ............ 0.000 0.000 Evaporation Loss ......... 0.000 0.000 Exfiltration Loss ........ 0.000 0.000 Initial Stored Volume .... 0.319 0.104 Final Stored Volume ...... 0.050 0.016 Continuity Error (%) ..... 0.012 ******************************** Highest Flow Instability Indexes ******************************** Link OUTOS2 (2) ************************* Routing Time Step Summary ************************* Minimum Time Step : 15.00 sec Average Time Step : 15.00 sec Maximum Time Step : 15.00 sec Percent in Steady State : 0.00 Average Iterations per Step : 1.00 Percent Not Converging : 0.00 *************************** Subcatchment Runoff Summary *************************** -------------------------------------------------------------------------------------------------------- Total Total Total Total Total Total Peak Runoff Precip Runon Evap Infil Runoff Runoff Runoff Coeff Page 2 SWMM - Developed 100-yr.rpt Subcatchment in in in in in 10^6 gal CFS -------------------------------------------------------------------------------------------------------- SUB-A 3.67 0.00 0.00 0.78 2.86 0.45 37.87 0.778 SUB-B 3.67 0.00 0.00 0.85 2.79 0.30 23.18 0.760 SUB-C 3.67 0.00 0.00 1.12 2.56 0.04 4.28 0.696 SUB-D 3.67 0.00 0.00 0.73 2.91 0.39 33.02 0.793 HT 3.67 0.00 0.00 2.10 1.58 0.24 11.01 0.430 OS1 3.67 0.00 0.00 2.10 1.57 0.63 26.35 0.427 OS2 3.67 0.00 0.00 2.22 1.45 2.51 99.12 0.395 SUB-UD2 3.67 0.00 0.00 2.10 1.59 0.17 8.71 0.432 ****************** Node Depth Summary ****************** --------------------------------------------------------------------------------- Average Maximum Maximum Time of Max Reported Depth Depth HGL Occurrence Max Depth Node Type Feet Feet Feet days hr:min Feet --------------------------------------------------------------------------------- J1 JUNCTION 0.09 1.31 42.01 0 02:09 1.31 J2 JUNCTION 0.10 1.31 40.41 0 02:20 1.31 J3 JUNCTION 0.27 1.39 35.59 0 00:53 1.39 J4 JUNCTION 0.03 1.11 39.33 0 00:50 1.11 J5 JUNCTION 0.01 0.61 46.21 0 01:02 0.61 J6 JUNCTION 0.18 0.33 36.83 0 02:25 0.33 J7 JUNCTION 0.18 0.33 35.33 0 02:29 0.33 O1 OUTFALL 0.02 1.11 36.61 0 00:50 1.11 O2 OUTFALL 0.27 1.39 34.99 0 00:53 1.39 O3 OUTFALL 0.00 0.00 48.00 0 00:00 0.00 POND1 STORAGE 2.79 5.11 45.11 0 02:23 5.11 POND2 STORAGE 1.23 2.83 39.83 0 02:26 2.83 POND3 STORAGE 0.67 3.42 45.42 0 02:09 3.42 POND4 STORAGE 0.96 6.58 43.18 0 02:10 6.58 PONDOS1 STORAGE 0.01 0.96 47.96 0 01:02 0.95 PONDOS2 STORAGE 0.15 6.15 50.15 0 01:37 6.15 ******************* Node Inflow Summary ******************* Page 3 SWMM - Developed 100-yr.rpt ------------------------------------------------------------------------------------------------- Maximum Maximum Lateral Total Flow Lateral Total Time of Max Inflow Inflow Balance Inflow Inflow Occurrence Volume Volume Error Node Type CFS CFS days hr:min 10^6 gal 10^6 gal Percent ------------------------------------------------------------------------------------------------- J1 JUNCTION 0.00 22.10 0 02:09 0 2.27 0.000 J2 JUNCTION 8.71 25.73 0 00:51 0.174 2.45 0.000 J3 JUNCTION 0.00 27.33 0 00:53 0 3.67 0.000 J4 JUNCTION 11.01 25.49 0 00:50 0.236 0.861 0.000 J5 JUNCTION 0.00 16.20 0 01:02 0 0.625 0.000 J6 JUNCTION 0.00 0.75 0 02:25 0 0.824 0.000 J7 JUNCTION 0.00 2.15 0 02:16 0 1.22 0.000 O1 OUTFALL 0.00 25.47 0 00:50 0 0.861 0.000 O2 OUTFALL 0.00 27.33 0 00:53 0 3.67 0.000 O3 OUTFALL 0.00 18.83 0 01:37 0 0.281 0.000 POND1 STORAGE 37.87 37.87 0 00:40 0.447 0.481 0.002 POND2 STORAGE 23.18 23.18 0 00:40 0.302 0.359 0.002 POND3 STORAGE 4.28 4.28 0 00:40 0.0444 0.048 0.007 POND4 STORAGE 33.02 33.02 0 00:40 0.386 0.396 0.015 PONDOS1 STORAGE 26.35 26.35 0 00:40 0.626 0.626 0.067 PONDOS2 STORAGE 99.12 99.12 0 00:40 2.51 2.51 0.018 ********************* Node Flooding Summary ********************* No nodes were flooded. ********************** Storage Volume Summary ********************** -------------------------------------------------------------------------------------------------- Average Avg Evap Exfil Maximum Max Time of Max Maximum Volume Pcnt Pcnt Pcnt Volume Pcnt Occurrence Outflow Storage Unit 1000 ft3 Full Loss Loss 1000 ft3 Full days hr:min CFS -------------------------------------------------------------------------------------------------- POND1 19.405 30 0 0 61.985 96 0 02:23 0.35 POND2 12.779 26 0 0 45.425 92 0 02:26 0.40 POND3 0.703 11 0 0 5.898 90 0 02:09 0.10 Page 4 SWMM - Developed 100-yr.rpt POND4 3.030 5 0 0 44.727 71 0 02:10 1.40 PONDOS1 0.102 0 0 0 11.701 3 0 01:01 16.20 PONDOS2 3.081 2 0 0 148.527 81 0 01:37 40.83 *********************** Outfall Loading Summary *********************** ----------------------------------------------------------- Flow Avg Max Total Freq Flow Flow Volume Outfall Node Pcnt CFS CFS 10^6 gal ----------------------------------------------------------- O1 2.93 8.66 25.47 0.861 O2 99.99 1.08 27.33 3.667 O3 0.71 11.64 18.83 0.281 ----------------------------------------------------------- System 34.54 21.38 62.18 4.809 ******************** Link Flow Summary ******************** ----------------------------------------------------------------------------- Maximum Time of Max Maximum Max/ Max/ |Flow| Occurrence |Veloc| Full Full Link Type CFS days hr:min ft/sec Flow Depth ----------------------------------------------------------------------------- 1 CONDUIT 22.10 0 02:20 3.21 0.03 0.26 2 CONDUIT 25.72 0 00:52 5.08 0.02 0.23 3 CONDUIT 27.33 0 00:53 3.54 0.03 0.28 8 CONDUIT 16.20 0 01:03 3.65 0.27 0.61 9 CONDUIT 25.47 0 00:50 5.20 0.07 0.37 10 CONDUIT 0.75 0 02:29 2.16 0.06 0.17 11 CONDUIT 2.15 0 02:16 7.85 0.04 0.14 BYPASS WEIR 18.83 0 01:37 0.00 POND2OVERFLOW WEIR 0.00 0 00:00 0.00 POND4OVERFLOW WEIR 0.00 0 00:00 0.00 OUT1 DUMMY 0.35 0 02:23 OUT2 DUMMY 0.40 0 02:26 OUT3 DUMMY 0.10 0 02:09 Page 5 SWMM - Developed 100-yr.rpt OUT4 DUMMY 1.40 0 02:10 OUTOS1 DUMMY 16.20 0 01:02 OUTOS2 DUMMY 22.00 0 01:26 ************************* Conduit Surcharge Summary ************************* No conduits were surcharged. Analysis begun on: Sat Feb 17 16:37:42 2018 Analysis ended on: Sat Feb 17 16:37:42 2018 Total elapsed time: < 1 sec Page 6 SWMM - Developed 100-yr Dixon Creek Clogged Upstream.rpt EPA STORM WATER MANAGEMENT MODEL - VERSION 5.1 (Build 5.1.012) -------------------------------------------------------------- ********************************************************* NOTE: The summary statistics displayed in this report are based on results found at every computational time step, not just on results from each reporting time step. ********************************************************* **************** Analysis Options **************** Flow Units ............... CFS Process Models: Rainfall/Runoff ........ YES RDII ................... NO Snowmelt ............... NO Groundwater ............ NO Flow Routing ........... YES Ponding Allowed ........ NO Water Quality .......... NO Infiltration Method ...... HORTON Flow Routing Method ...... KINWAVE Starting Date ............ 03/15/2016 00:00:00 Ending Date .............. 03/20/2016 06:00:00 Antecedent Dry Days ...... 0.0 Report Time Step ......... 00:05:00 Wet Time Step ............ 00:05:00 Dry Time Step ............ 01:00:00 Routing Time Step ........ 15.00 sec ************************** Volume Depth Runoff Quantity Continuity acre-feet inches ************************** --------- ------- Total Precipitation ...... 31.552 3.669 Evaporation Loss ......... 0.000 0.000 Infiltration Loss ........ 17.014 1.979 Surface Runoff ........... 14.493 1.685 Final Storage ............ 0.131 0.015 Continuity Error (%) ..... -0.274 Page 1 SWMM - Developed 100-yr Dixon Creek Clogged Upstream.rpt ************************** Volume Volume Flow Routing Continuity acre-feet 10^6 gal ************************** --------- --------- Dry Weather Inflow ....... 0.000 0.000 Wet Weather Inflow ....... 14.493 4.723 Groundwater Inflow ....... 0.000 0.000 RDII Inflow .............. 0.000 0.000 External Inflow .......... 0.000 0.000 External Outflow ......... 11.489 3.744 Flooding Loss ............ 0.000 0.000 Evaporation Loss ......... 0.000 0.000 Exfiltration Loss ........ 0.000 0.000 Initial Stored Volume .... 0.319 0.104 Final Stored Volume ...... 3.318 1.081 Continuity Error (%) ..... 0.039 ******************************** Highest Flow Instability Indexes ******************************** All links are stable. ************************* Routing Time Step Summary ************************* Minimum Time Step : 15.00 sec Average Time Step : 15.00 sec Maximum Time Step : 15.00 sec Percent in Steady State : 0.00 Average Iterations per Step : 1.00 Percent Not Converging : 0.00 *************************** Subcatchment Runoff Summary *************************** -------------------------------------------------------------------------------------------------------- Total Total Total Total Total Total Peak Runoff Precip Runon Evap Infil Runoff Runoff Runoff Coeff Page 2 SWMM - Developed 100-yr Dixon Creek Clogged Upstream.rpt Subcatchment in in in in in 10^6 gal CFS -------------------------------------------------------------------------------------------------------- SUB-A 3.67 0.00 0.00 0.78 2.86 0.45 37.87 0.778 SUB-B 3.67 0.00 0.00 0.85 2.79 0.30 23.18 0.760 SUB-C 3.67 0.00 0.00 1.12 2.56 0.04 4.28 0.696 SUB-D 3.67 0.00 0.00 0.73 2.91 0.39 33.02 0.793 HT 3.67 0.00 0.00 2.10 1.58 0.24 11.01 0.430 OS1 3.67 0.00 0.00 2.10 1.57 0.63 26.35 0.427 OS2 3.67 0.00 0.00 2.22 1.45 2.51 99.12 0.395 SUB-UD2 3.67 0.00 0.00 2.10 1.59 0.17 8.71 0.432 ****************** Node Depth Summary ****************** --------------------------------------------------------------------------------- Average Maximum Maximum Time of Max Reported Depth Depth HGL Occurrence Max Depth Node Type Feet Feet Feet days hr:min Feet --------------------------------------------------------------------------------- J1 JUNCTION 0.05 0.17 40.87 0 02:09 0.17 J2 JUNCTION 0.07 0.75 39.85 0 00:45 0.75 J3 JUNCTION 0.24 0.96 35.16 0 00:46 0.95 J4 JUNCTION 0.03 1.11 39.33 0 00:50 1.11 J5 JUNCTION 0.01 0.61 46.21 0 01:02 0.61 J6 JUNCTION 0.18 0.33 36.83 0 02:25 0.33 J7 JUNCTION 0.18 0.33 35.33 0 02:29 0.33 O1 OUTFALL 0.02 1.11 36.61 0 00:50 1.11 O2 OUTFALL 0.24 0.96 34.56 0 00:47 0.95 O3 OUTFALL 0.00 0.00 48.00 0 00:00 0.00 POND1 STORAGE 2.79 5.11 45.11 0 02:23 5.11 POND2 STORAGE 1.23 2.83 39.83 0 02:26 2.83 POND3 STORAGE 0.67 3.42 45.42 0 02:09 3.42 POND4 STORAGE 0.96 6.58 43.18 0 02:10 6.58 PONDOS1 STORAGE 0.01 0.96 47.96 0 01:02 0.95 PONDOS2 STORAGE 5.97 6.29 50.29 0 01:15 6.29 ******************* Node Inflow Summary ******************* Page 3 SWMM - Developed 100-yr Dixon Creek Clogged Upstream.rpt ------------------------------------------------------------------------------------------------- Maximum Maximum Lateral Total Flow Lateral Total Time of Max Inflow Inflow Balance Inflow Inflow Occurrence Volume Volume Error Node Type CFS CFS days hr:min 10^6 gal 10^6 gal Percent ------------------------------------------------------------------------------------------------- J1 JUNCTION 0.00 0.10 0 02:09 0 0.048 0.000 J2 JUNCTION 8.71 8.76 0 00:45 0.174 0.222 0.000 J3 JUNCTION 0.00 10.10 0 00:46 0 1.44 0.000 J4 JUNCTION 11.01 25.49 0 00:50 0.236 0.861 0.000 J5 JUNCTION 0.00 16.20 0 01:02 0 0.625 0.000 J6 JUNCTION 0.00 0.75 0 02:25 0 0.824 0.000 J7 JUNCTION 0.00 2.15 0 02:16 0 1.22 0.000 O1 OUTFALL 0.00 25.47 0 00:50 0 0.861 0.000 O2 OUTFALL 0.00 10.10 0 00:47 0 1.44 0.000 O3 OUTFALL 0.00 50.82 0 01:15 0 1.44 0.000 POND1 STORAGE 37.87 37.87 0 00:40 0.447 0.481 0.002 POND2 STORAGE 23.18 23.18 0 00:40 0.302 0.359 0.002 POND3 STORAGE 4.28 4.28 0 00:40 0.0444 0.048 0.007 POND4 STORAGE 33.02 33.02 0 00:40 0.386 0.396 0.015 PONDOS1 STORAGE 26.35 26.35 0 00:40 0.626 0.626 0.067 PONDOS2 STORAGE 99.12 99.12 0 00:40 2.51 2.51 0.061 ********************* Node Flooding Summary ********************* No nodes were flooded. ********************** Storage Volume Summary ********************** -------------------------------------------------------------------------------------------------- Average Avg Evap Exfil Maximum Max Time of Max Maximum Volume Pcnt Pcnt Pcnt Volume Pcnt Occurrence Outflow Storage Unit 1000 ft3 Full Loss Loss 1000 ft3 Full days hr:min CFS -------------------------------------------------------------------------------------------------- POND1 19.405 30 0 0 61.985 96 0 02:23 0.35 POND2 12.779 26 0 0 45.425 92 0 02:26 0.40 POND3 0.703 11 0 0 5.898 90 0 02:09 0.10 Page 4 SWMM - Developed 100-yr Dixon Creek Clogged Upstream.rpt POND4 3.030 5 0 0 44.727 71 0 02:10 1.40 PONDOS1 0.102 0 0 0 11.701 3 0 01:01 16.20 PONDOS2 141.600 77 0 0 154.329 84 0 01:15 50.82 *********************** Outfall Loading Summary *********************** ----------------------------------------------------------- Flow Avg Max Total Freq Flow Flow Volume Outfall Node Pcnt CFS CFS 10^6 gal ----------------------------------------------------------- O1 2.93 8.66 25.47 0.861 O2 99.99 0.43 10.10 1.442 O3 5.62 7.55 50.82 1.440 ----------------------------------------------------------- System 36.18 16.64 77.93 3.743 ******************** Link Flow Summary ******************** ----------------------------------------------------------------------------- Maximum Time of Max Maximum Max/ Max/ |Flow| Occurrence |Veloc| Full Full Link Type CFS days hr:min ft/sec Flow Depth ----------------------------------------------------------------------------- 1 CONDUIT 0.10 0 02:14 0.83 0.00 0.03 2 CONDUIT 8.70 0 00:46 3.88 0.01 0.15 3 CONDUIT 10.10 0 00:47 2.76 0.01 0.19 8 CONDUIT 16.20 0 01:03 3.65 0.27 0.61 9 CONDUIT 25.47 0 00:50 5.20 0.07 0.37 10 CONDUIT 0.75 0 02:29 2.16 0.06 0.17 11 CONDUIT 2.15 0 02:16 7.85 0.04 0.14 BYPASS WEIR 50.82 0 01:15 0.00 POND2OVERFLOW WEIR 0.00 0 00:00 0.00 POND4OVERFLOW WEIR 0.00 0 00:00 0.00 OUT1 DUMMY 0.35 0 02:23 OUT2 DUMMY 0.40 0 02:26 OUT3 DUMMY 0.10 0 02:09 Page 5 SWMM - Developed 100-yr Dixon Creek Clogged Upstream.rpt OUT4 DUMMY 1.40 0 02:10 OUTOS1 DUMMY 16.20 0 01:02 OUTOS2 DUMMY 0.00 0 00:00 ************************* Conduit Surcharge Summary ************************* No conduits were surcharged. Analysis begun on: Sat Feb 17 16:39:16 2018 Analysis ended on: Sat Feb 17 16:39:16 2018 Total elapsed time: < 1 sec Page 6 SWMM - Developed 100-yr Pond 2 and 4 Clogged.rpt EPA STORM WATER MANAGEMENT MODEL - VERSION 5.1 (Build 5.1.012) -------------------------------------------------------------- ********************************************************* NOTE: The summary statistics displayed in this report are based on results found at every computational time step, not just on results from each reporting time step. ********************************************************* **************** Analysis Options **************** Flow Units ............... CFS Process Models: Rainfall/Runoff ........ YES RDII ................... NO Snowmelt ............... NO Groundwater ............ NO Flow Routing ........... YES Ponding Allowed ........ NO Water Quality .......... NO Infiltration Method ...... HORTON Flow Routing Method ...... KINWAVE Starting Date ............ 03/15/2016 00:00:00 Ending Date .............. 03/20/2016 06:00:00 Antecedent Dry Days ...... 0.0 Report Time Step ......... 00:05:00 Wet Time Step ............ 00:05:00 Dry Time Step ............ 01:00:00 Routing Time Step ........ 15.00 sec ************************** Volume Depth Runoff Quantity Continuity acre-feet inches ************************** --------- ------- Total Precipitation ...... 31.552 3.669 Evaporation Loss ......... 0.000 0.000 Infiltration Loss ........ 17.014 1.979 Surface Runoff ........... 14.493 1.685 Final Storage ............ 0.131 0.015 Continuity Error (%) ..... -0.274 ************************** Volume Volume Page 1 SWMM - Developed 100-yr Pond 2 and 4 Clogged.rpt Flow Routing Continuity acre-feet 10^6 gal ************************** --------- --------- Dry Weather Inflow ....... 0.000 0.000 Wet Weather Inflow ....... 14.493 4.723 Groundwater Inflow ....... 0.000 0.000 RDII Inflow .............. 0.000 0.000 External Inflow .......... 0.000 0.000 External Outflow ......... 12.516 4.078 Flooding Loss ............ 0.000 0.000 Evaporation Loss ......... 0.000 0.000 Exfiltration Loss ........ 0.000 0.000 Initial Stored Volume .... 0.319 0.104 Final Stored Volume ...... 2.295 0.748 Continuity Error (%) ..... 0.012 ******************************** Highest Flow Instability Indexes ******************************** Link OUTOS2 (2) ************************* Routing Time Step Summary ************************* Minimum Time Step : 15.00 sec Average Time Step : 15.00 sec Maximum Time Step : 15.00 sec Percent in Steady State : 0.00 Average Iterations per Step : 1.00 Percent Not Converging : 0.00 *************************** Subcatchment Runoff Summary *************************** -------------------------------------------------------------------------------------------------------- Total Total Total Total Total Total Peak Runoff Precip Runon Evap Infil Runoff Runoff Runoff Coeff Subcatchment in in in in in 10^6 gal CFS -------------------------------------------------------------------------------------------------------- SUB-A 3.67 0.00 0.00 0.78 2.86 0.45 37.87 0.778 SUB-B 3.67 0.00 0.00 0.85 2.79 0.30 23.18 0.760 SUB-C 3.67 0.00 0.00 1.12 2.56 0.04 4.28 0.696 SUB-D 3.67 0.00 0.00 0.73 2.91 0.39 33.02 0.793 Page 2 SWMM - Developed 100-yr Pond 2 and 4 Clogged.rpt HT 3.67 0.00 0.00 2.10 1.58 0.24 11.01 0.430 OS1 3.67 0.00 0.00 2.10 1.57 0.63 26.35 0.427 OS2 3.67 0.00 0.00 2.22 1.45 2.51 99.12 0.395 SUB-UD2 3.67 0.00 0.00 2.10 1.59 0.17 8.71 0.432 ****************** Node Depth Summary ****************** --------------------------------------------------------------------------------- Average Maximum Maximum Time of Max Reported Depth Depth HGL Occurrence Max Depth Node Type Feet Feet Feet days hr:min Feet --------------------------------------------------------------------------------- J1 JUNCTION 0.09 1.31 42.01 0 02:09 1.31 J2 JUNCTION 0.10 1.31 40.41 0 02:20 1.31 J3 JUNCTION 0.22 1.36 35.56 0 00:52 1.36 J4 JUNCTION 0.03 1.11 39.33 0 00:50 1.11 J5 JUNCTION 0.01 0.61 46.21 0 01:02 0.61 J6 JUNCTION 0.14 0.30 36.80 0 02:33 0.30 J7 JUNCTION 0.14 0.30 35.30 0 02:36 0.30 O1 OUTFALL 0.02 1.11 36.61 0 00:50 1.11 O2 OUTFALL 0.22 1.36 34.96 0 00:52 1.36 O3 OUTFALL 0.00 0.00 48.00 0 00:00 0.00 POND1 STORAGE 2.79 5.11 45.11 0 02:23 5.11 POND2 STORAGE 2.87 2.92 39.92 0 02:33 2.92 POND3 STORAGE 0.67 3.42 45.42 0 02:09 3.42 POND4 STORAGE 6.96 7.01 43.61 0 02:35 7.01 PONDOS1 STORAGE 0.01 0.96 47.96 0 01:02 0.95 PONDOS2 STORAGE 0.15 6.15 50.15 0 01:37 6.15 ******************* Node Inflow Summary ******************* ------------------------------------------------------------------------------------------------- Maximum Maximum Lateral Total Flow Lateral Total Time of Max Inflow Inflow Balance Inflow Inflow Occurrence Volume Volume Error Node Type CFS CFS days hr:min 10^6 gal 10^6 gal Percent ------------------------------------------------------------------------------------------------- J1 JUNCTION 0.00 22.10 0 02:09 0 2.27 0.000 J2 JUNCTION 8.71 25.73 0 00:51 0.174 2.45 0.000 J3 JUNCTION 0.00 25.95 0 00:52 0 2.94 0.000 Page 3 SWMM - Developed 100-yr Pond 2 and 4 Clogged.rpt J4 JUNCTION 11.01 25.49 0 00:50 0.236 0.861 0.000 J5 JUNCTION 0.00 16.20 0 01:02 0 0.625 0.000 J6 JUNCTION 0.00 0.58 0 02:33 0 0.486 0.000 J7 JUNCTION 0.00 0.58 0 02:36 0 0.486 0.000 O1 OUTFALL 0.00 25.47 0 00:50 0 0.861 0.000 O2 OUTFALL 0.00 25.95 0 00:52 0 2.94 0.000 O3 OUTFALL 0.00 18.83 0 01:37 0 0.281 0.000 POND1 STORAGE 37.87 37.87 0 00:40 0.447 0.481 0.002 POND2 STORAGE 23.18 23.18 0 00:40 0.302 0.359 0.000 POND3 STORAGE 4.28 4.28 0 00:40 0.0444 0.048 0.007 POND4 STORAGE 33.02 33.02 0 00:40 0.386 0.396 0.000 PONDOS1 STORAGE 26.35 26.35 0 00:40 0.626 0.626 0.067 PONDOS2 STORAGE 99.12 99.12 0 00:40 2.51 2.51 0.018 ********************* Node Flooding Summary ********************* No nodes were flooded. ********************** Storage Volume Summary ********************** -------------------------------------------------------------------------------------------------- Average Avg Evap Exfil Maximum Max Time of Max Maximum Volume Pcnt Pcnt Pcnt Volume Pcnt Occurrence Outflow Storage Unit 1000 ft3 Full Loss Loss 1000 ft3 Full days hr:min CFS -------------------------------------------------------------------------------------------------- POND1 19.405 30 0 0 61.985 96 0 02:23 0.35 POND2 46.284 94 0 0 47.564 96 0 02:33 0.23 POND3 0.703 11 0 0 5.898 90 0 02:09 0.10 POND4 52.119 83 0 0 52.724 84 0 02:35 0.08 PONDOS1 0.102 0 0 0 11.701 3 0 01:01 16.20 PONDOS2 3.081 2 0 0 148.527 81 0 01:37 40.83 *********************** Outfall Loading Summary *********************** ----------------------------------------------------------- Flow Avg Max Total Freq Flow Flow Volume Page 4 SWMM - Developed 100-yr Pond 2 and 4 Clogged.rpt Outfall Node Pcnt CFS CFS 10^6 gal ----------------------------------------------------------- O1 2.93 8.66 25.47 0.861 O2 99.96 0.87 25.95 2.936 O3 0.71 11.64 18.83 0.281 ----------------------------------------------------------- System 34.53 21.17 60.48 4.078 ******************** Link Flow Summary ******************** ----------------------------------------------------------------------------- Maximum Time of Max Maximum Max/ Max/ |Flow| Occurrence |Veloc| Full Full Link Type CFS days hr:min ft/sec Flow Depth ----------------------------------------------------------------------------- 1 CONDUIT 22.10 0 02:20 3.21 0.03 0.26 2 CONDUIT 25.72 0 00:52 5.08 0.02 0.23 3 CONDUIT 25.95 0 00:52 3.49 0.03 0.27 8 CONDUIT 16.20 0 01:03 3.65 0.27 0.61 9 CONDUIT 25.47 0 00:50 5.20 0.07 0.37 10 CONDUIT 0.58 0 02:36 2.01 0.05 0.15 11 CONDUIT 0.58 0 02:36 5.27 0.01 0.08 BYPASS WEIR 18.83 0 01:37 0.00 POND2OVERFLOW WEIR 0.23 0 02:33 0.00 POND4OVERFLOW WEIR 0.08 0 02:35 0.00 OUT1 DUMMY 0.35 0 02:23 OUT2 DUMMY 0.00 0 00:00 OUT3 DUMMY 0.10 0 02:09 OUT4 DUMMY 0.00 0 00:00 OUTOS1 DUMMY 16.20 0 01:02 OUTOS2 DUMMY 22.00 0 01:26 ************************* Conduit Surcharge Summary ************************* No conduits were surcharged. Analysis begun on: Sat Feb 17 16:38:23 2018 Analysis ended on: Sat Feb 17 16:38:24 2018 Total elapsed time: 00:00:01 Page 5 APPENDIX F REFERENCES Hydrologic Soil Group—Larimer County Area, Colorado (Mountain's Edge) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/21/2016 Page 1 of 4 4489080 4489140 4489200 4489260 4489320 4489380 4489440 4489500 4489560 4489080 4489140 4489200 4489260 4489320 4489380 4489440 4489500 4489560 488580 488640 488700 488760 488820 488880 488940 488580 488640 488700 488760 488820 488880 488940 40° 33' 24'' N 105° 8' 5'' W 40° 33' 24'' N 105° 7' 50'' W 40° 33' 8'' N 105° 8' 5'' W 40° 33' 8'' N 105° 7' 50'' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 100 200 400 600 Feet 0 35 70 140 210 Meters Map Scale: 1:2,410 if printed on A portrait (8.5" x 11") sheet. Warning: Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons A A/D B B/D C C/D D Not rated or not available Soil Rating Lines A A/D B B/D C C/D D Not rated or not available Soil Rating Points A A/D B B/D C C/D D Not rated or not available Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Larimer County Area, Colorado Hydrologic Soil Group Hydrologic Soil Group— Summary by Map Unit — Larimer County Area, Colorado (CO644) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 3 Altvan-Satanta loams, 0 to 3 percent slopes B 8.7 42.7% 4 Altvan-Satanta loams, 3 to 9 percent slopes B 11.6 57.3% Totals for Area of Interest 20.3 100.0% 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 Hydrologic Soil Group—Larimer County Area, Colorado Mountain's Edge Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/21/2016 Page 3 of 4 Component Percent Cutoff: None Specified Tie-break Rule: Higher Hydrologic Soil Group—Larimer County Area, Colorado Mountain's Edge Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/21/2016 Page 4 of 4 MAP POCKET DR1 – OVERALL DRAINAGE EXHIBIT X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X These drawings are instruments of service provided by Northern Engineering Services, Inc. and are not to be used for any type of construction unless signed and sealed by a Professional Engineer in the employ of Northern Engineering Services, Inc. NOT FOR CONSTRUCTION 301 North Howes Street, Suite 100 Fort Collins, Colorado 80521 N O R T H E RN PHONE: 970.221.4158 www.northernengineering.com DR1 CALL UTILITY NOTIFICATION CENTER OF COLORADO Know what's R CityDate Engineer Date Date Date Date Stormwater Utility Parks & Recreation Traffic Engineer Date Water & Wastewater Utility City of Fort Collins, Colorado UTILITY PLAN APPROVAL Environmental Planner ( IN FEET ) 0 1 INCH = 60 FEET 60 60 120 180 LEGEND: 5013 PROPOSED CONTOUR 93 EXISTING CONTOUR PROPERTY BOUNDARY EXISTING STORM SEWER 1. THE SIZE, TYPE AND LOCATION OF ALL KNOWN UNDERGROUND UTILITIES ARE APPROXIMATE WHEN SHOWN ON THESE DRAWINGS. IT SHALL BE THE RESPONSIBILITY OF THE CONTRACTOR TO VERIFY THE EXISTENCE OF ALL UNDERGROUND UTILITIES IN THE AREA OF THE WORK. BEFORE COMMENCING NEW CONSTRUCTION, THE CONTRACTOR SHALL BE RESPONSIBLE FOR LOCATING ALL UNDERGROUND UTILITIES AND SHALL BE RESPONSIBLE FOR FOR ALL UNKNOWN UNDERGROUND UTILITIES. 2. REFER TO THE"Final Drainage Report for Mountains Edge " BY NORTHERN ENGINEERING, DATED February 20, 2018 FOR ADDITIONAL INFORMATION. NOTES: FLOW PATH DRAINAGE BASIN BUBBLE A DESIGN POINT A BASIN BOUNDARY PROPOSED STORM SEWER FOR DRAINAGE REVIEW ONLY NOT FOR CONSTRUCTION Detention Pond Summary | Proposed Condition Pond 100-yr Volume (ac-ft) 100-yr WSEL WQCV (ft3) WQCV WSEL Max Release (cfs) 1 1.42 5145.31 3,251 5141.80 0.35 2 1.04 5140.04 2,987 5137.87 0.40 3 0.14 5145.62 296 5143.01 0.10 4 1.03 5142.04 970 5136.45 1.40 DRAINAGE SUMMARY TABLE DESIGN POINT BASIN ID TOTAL AREA (acres) C2 C100 2-yr Tc (min) 100-yr Tc (min) Q2 (cfs) Q100 (cfs) A1 A1 1.45 0.74 0.92 5.0 5.0 3.04 13.25 A2 A2 0.27 0.59 0.73 5.0 5.0 0.45 1.95 A3 A3 0.23 0.57 0.71 5.0 5.0 0.38 1.64 A4 A4 0.25 0.58 0.72 5.0 5.0 0.42 1.83 A5 A5 1.14 0.89 1.00 6.7 5.6 2.63 10.95 A6 A6 0.34 0.67 0.83 5.0 5.0 0.65 2.86 A7 A7 0.41 0.55 0.69 12.6 9.5 0.45 2.21 A8 A8 1.54 0.41 0.52 9.3 8.1 1.46 6.66 B1 B1 0.42 0.95 1.00 5.2 5.0 1.13 4.14 B2 B2 0.62 0.59 0.74 6.1 5.4 0.98 4.57 B3 B3 1.22 0.83 1.00 5.0 5.0 2.86 12.10 B4 B4 0.06 0.72 0.90 5.0 5.0 0.12 0.52 B5 B5 0.19 0.78 0.98 5.0 5.0 0.42 1.82 B6 B6 0.40 0.50 0.62 10.3 9.1 0.44 2.02 B7 B7 1.09 0.30 0.38 6.9 6.4 0.86 3.85 C1 C1 0.15 0.56 0.70 5.0 5.0 0.25 1.08 C2 C2 0.48 0.39 0.48 5.8 5.1 0.51 2.31 D1 D1 0.25 0.95 1.00 5.0 5.0 0.68 2.50 D2 D2 1.66 0.71 0.89 5.0 5.0 3.36 14.65 D3 D3 0.88 0.75 0.94 5.3 5.0 1.88 8.22 D4 D4 0.65 0.70 0.88 5.0 5.0 1.30 5.67 D5 D5 0.89 0.42 0.53 8.3 7.4 0.90 4.13 D6 D6 0.57 0.39 0.48 7.1 6.4 0.56 2.57 UD1 UD1 0.05 0.83 1.00 5.0 5.0 0.12 0.52 UD2 UD2 4.05 0.26 0.33 14.2 13.7 2.04 9.04 HT1 HT1 16.86 0.39 0.49 36.8 32.0 7.50 36.00 OS1 OS1 14.72 0.33 0.41 23.7 23.2 7.06 31.10 X X X X / / / / / / / / / / / / / / / / X X X X X X X X X X X X X X X X OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / / GAS MM T W VAULT F.O. B M D T C F E S C ONTROL IRR S H2O H2O H2O 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 16" W 16" W 16" W 16" W 16" W 16" W 16" W 16" W 16" W HA1 HA2 HB1 HB2 HA3 1 2 HB3 3 8" SS 6" W 6" W 6" W 6" W 6" W 6" W 6" W 6" W 6" W 6" W 6" W 8" SS 8" SS 8" SS 8" SS 8" SS 8" SS 8" SS 6" W 6" W S 6" W S S OVERLAND TRAIL BLUEGRASS DRIVE DRAKE ROAD Sheet MOUNTAIN'S EDGE These drawings are instruments of service provided by Northern Engineering Services, Inc. and are not to be used for any type of construction unless signed and sealed by a Professional Engineer in the employ of Northern Engineering Services, Inc. NOT FOR CONSTRUCTION REVIEW SET 301 North Howes Street, Suite 100 Fort Collins, Colorado 80521 E NGINEER ING N O R T H E RN PHONE: 970.221.4158 www.northernengineering.com of 23 HDR1 HISTORIC DRAINAGE EXHIBIT CALL UTILITY NOTIFICATION CENTER OF COLORADO Know what'sbelow. Call before you dig. R ( IN FEET ) 0 1 INCH = 60 FEET 60 60 120 180 LEGEND: 5013 PROPOSED CONTOUR 93 EXISTING CONTOUR PROPERTY BOUNDARY EXISTING STORM SEWER 1. THE SIZE, TYPE AND LOCATION OF ALL KNOWN UNDERGROUND UTILITIES ARE APPROXIMATE WHEN SHOWN ON THESE DRAWINGS. IT SHALL BE THE RESPONSIBILITY OF THE CONTRACTOR TO VERIFY THE EXISTENCE OF ALL UNDERGROUND UTILITIES IN THE AREA OF THE WORK. BEFORE COMMENCING NEW CONSTRUCTION, THE CONTRACTOR SHALL BE RESPONSIBLE FOR LOCATING ALL UNDERGROUND UTILITIES AND SHALL BE RESPONSIBLE FOR FOR ALL UNKNOWN UNDERGROUND UTILITIES. 2. REFER TO THE "PRELIMINARY DRAINAGE AND EROSION CONTROL REPORT FOR MOUNTAIN'S EDGE" BY NORTHERN ENGINEERING, DATED DECEMBER 20TH, 2016 FOR ADDITIONAL INFORMATION. NOTES: FLOW PATH DRAINAGE BASIN BUBBLE A DESIGN POINT A BASIN BOUNDARY PROPOSED STORM SEWER FOR DRAINAGE REVIEW ONLY NOT FOR CONSTRUCTION DRAINAGE SUMMARY TABLE DESIGN POINT BASIN ID TOTAL AREA (acres) C2 C100 2-yr Tc (min) 100-yr Tc (min) Q2 (cfs) Q100 (cfs) 1 HA1 4.07 0.25 0.31 14.3 13.9 1.96 8.68 1 HA2 4.18 0.25 0.31 31.8 29.9 1.31 5.95 1 HA3 0.33 0.57 0.71 24.0 19.4 0.27 1.33 2 HB1 5.60 0.25 0.31 21.4 20.3 2.18 9.80 2 HB2 0.47 0.57 0.71 15.9 13.5 0.49 2.29 3 HB3 4.66 0.25 0.31 37.2 34.5 1.32 6.06 Survey Area Data: Version 11, Sep 23, 2016 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Apr 22, 2011—Apr 28, 2011 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Hydrologic Soil Group—Larimer County Area, Colorado (Mountain's Edge) Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 12/21/2016 Page 2 of 4 L OP L Y N D U TC LI E I R O N T AS L OP L NY D U TC I L E I R O N ST A PL O YL N UD C IT EL RI O N T AS L OP L Y N D U TC LI E I R O N T AS L OP L NY D U TC I L E RI O N ST A PL O L Y N D CU IT L E RI O N T AS L OP L NY UD TC I EL I R NO T S LA P LO NY D U TC LI E I OR N ST A PL O L Y N D U C IT L E RI O N ST A PL O L Y N UD C IT EL I R NO ST A L P LO Y N D CU T I L E RI O N T S LA OP NYL D U TC LI E I OR N T S LA P O L NY D U C T LI E I OR N ST LA P LO Y N D CU T I L E RI O N ST A PL O YL N D U C IT L E RI O N T LAS OP L NY D U TC LI E RI O N T AS L P YLO N UD C IT EL I R O N ST A PL O YL N D CU IT L E RI O N T AS L OP L NY D U C T LI E I R O N T S LA OP NYL D U C T LI E I R O N T AS L OP L Y N D U TC LI E RI O N T S LA P O L Y N D CU T LI E I NOR UD RAIN GARDEN #2 DETENTION POND 1 DETENTION POND 3 DETENTION POND 4 DETENTION POND 2 DOWNS WAY UPLAND DRIVE RIDGE TOP DRIVE CROWN VIEW DRIVE PRECIPICE DRIVE OVERLAND TRAIL BLUEGRASS DRIVE KNOLLS END DRIVE DRAKE ROAD CREST TOP DRIVE DIXON CREEK RAIN GARDEN #1 X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHE OHU GAS B M D T C F E S S H2O H2O WV H2O WV 60" W 60" W 60" W 60" W 60" W 60" W 60" W 60" W 60" W 60" W 60" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W FCLWD 18" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W 20" W FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO FO CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV CTV E E E E E E E E X CTV CTV E G X X OHU OHU OHU OHU OHU OHU OHU OHU OHU OHU OHU OHU OHU X X X X X X X X X X X V AULT F.O. W C H2O VAULT F.O. C 8" SS 6" W 6" W 6" W 6" W 6" W 6" W 6" W 6" W 6" W 6" W 6" W 6" W 6" W S 6" W 8" SS 8" SS 8" SS 8" SS 8" SS 8" SS 8" SS S S A1 A5 A8 B2 B1 B5 B7 C1 C2 D1 D2 D3 D4 D5 UD1 UD2 A4 A3 A2 B4 D6 A6 A7 B6 B3 L1 A1 L2 D1-D5 Sheet MOUNTAIN'S EDGE These drawings are instruments of service provided by Northern Engineering Services, Inc. and are not to be used for any type of construction unless signed and sealed by a Professional Engineer in the employ of Northern Engineering Services, Inc. NOT FOR CONSTRUCTION REVIEW SET 301 North Howes Street, Suite 100 Fort Collins, Colorado 80521 E NGINEER ING N O R T H E RN PHONE: 970.221.4158 www.northernengineering.com of 68 LID (LID) EXHIBIT LOW IMPACT DEVELOPMENT ( IN FEET ) 0 1 INCH = 60 FEET 60 60 120 180 LEGEND: 5013 PROPOSED CONTOUR 93 EXISTING CONTOUR PROPERTY BOUNDARY DRAINAGE BASIN BUBBLE A LID BASIN BOUNDARY PROPOSED STORM SEWER LID TREATMENT MEASURE DRAINAGE BASIN BOUNDARY L1 A2, A3 LID BASIN BUBBLE LID BASIN DESIGNATION CONTRIBUTING DRAINAGE BASINS RAIN GARDEN SUMMARY Rain Garden 1 Rain Garden 2 Total Contributing Area (sf) 63,123 188,303 Percent Impervious 65% 57% Total Volume Required (cf) 1,086 2,843 Total Volume Provided (cf) 1,255 3,154 LID TREATMENT SUMMARY Total Site Area (sf) 662,152 Total Overland ROW Impervious Area not required to be treated (sf) (Basins B1, D1) 32,318 Total Proposed Impervious Area (sf) 334,115 Total Net Proposed Impervious Area (sf) 301,796 50% Required Minimum Area to be Treated by LID measures (sf) 150,898 Total Treated Impervious Area (sf) 149,152 Percent Impervious Treated by LID measures 49.4% PROPOSED LID TREATED AREA LID BASIN NODE Sub-Basin(s) Area, A (sf) Percent Impervious Impervious Area, A (sf) LID Treatment L1 A1 63,123 65% 41,335 Rain Garden 1 Total L1 63,123 65% 41,335 L2 D1 10,927 99% 10,871 Rain Garden 2 D2 72,144 62% 44,888 D3 38,358 68% 26,248 D4 28,254 61% 17,175 D5 38,620 22% 8,635 Total L2 188,303 57% 107,817 Total Treated 251,426 59% 149,152 PROPOSED LID UNTREATED AREA LID BASIN NODE Sub-Basin(s) Area, A (sf) Percent Impervious Impervious Area, A (sf) A2 11,641 43% 5,051 A3 10,068 41% 4,149 A4 11,096 42% 4,679 A5 49,551 84% 41,724 A6 15,003 55% 8,211 A7 17,678 39% 6,916 A8 66,983 21% 14,066 B1 18,143 99% 18,010 B2 26,995 44% 11,906 B3 52,955 77% 40,698 B4 2,534 66% 1,662 B5 8,132 74% 6,013 B6 17,641 33% 5,806 B7 47,481 7% 3,399 C1 6,746 40% 2,715 C2 20,976 17% 3,648 D6 24,840 18% 4,500 UD1 2,263 80% 1,810 Total Proposed Untreated 410,726 45% 184,963 AREA NOT REQUIRED TO BE TREATED WITH LID B1 18,143 99% 18,010 D1 10,927 99% 10,871 Overland Sidewalk in Basins A2, A3, A4, B2, B3, C1 3,819 90% 3,437 Total Overland Trail ROW 32,889 98% 32,318 Rain Garden 1 AREA NOT REQUIRED TO BE TREATED WITH LID Overland Sidewalk in Basins A2, A3, A4, B2, B3, C1 Orifice Flow Q = 3 . 0 P H 1 . 5 Q = 0 . 67 A ( 2 gH ) 0 . 5 Q = 3 . 0 P H 1 . 5 Q = 0 . 67 A ( 2 gH ) 0 . 5 Q = 3 . 0 P H 1 . 5 Q = 0 . 67 A ( 2 gH ) 0 . 5 Stage - Discharge Curves Weir Flow Orifice Flow Q = 3 . 0 P H 1 . 5 Q = 0 . 67 A ( 2 gH ) 0 . 5 Q = 3 . 0 P H 1 . 5 Q = 0 . 67 A ( 2 gH ) 0 . 5 Q = 3 . 0 P H 1 . 5 Q = 0 . 67 A ( 2 gH ) 0 . 5 Weir Flow Orifice Flow Q = 3 . 0 P H 1 . 5 Q = 0 . 67 A ( 2 gH ) 0 . 5 Orifice Flow Q = 3 . 0 P H 1 . 5 Q = 0 . 67 A ( 2 gH ) 0 . 5 Orifice Flow Q = 3 . 0 P H 1 . 5 Q = 0 . 67 A ( 2 gH ) 0 . 5 Orifice Flow Q = 3 . 0 P H 1 . 5 Q = 0 . 67 A ( 2 gH ) 0 . 5 5,142.20 17,127 0.20 3346 47367 3345 47338 5,142.40 18,021 0.20 3515 50881 3514 50852 5,142.60 19,033 0.20 3705 54587 3705 54557 5,142.80 20,159 0.20 3919 58506 3919 58476 5,143.00 21,440 0.20 4160 62666 4159 62635 Design Point Design Storm Require Volume= Stage - Storage Calculation Project Number: Project Location: Calculations By: Required Volume Water Surface Elevation (WSE) 2/17/20183:40 PM D:\Projects\911-007\Drainage\Detention\911-007_Detention Pond 4.xlsm\Stage_Storage Required Volume Water Surface Elevation (WSE) 2/17/20183:36 PM D:\Projects\911-007\Drainage\Detention\911-007_Detention Pond 1.xlsm\Stage_Storage C2 Flow, Q10 (cfs) Intensity, i100 (in/hr) Sub-Basin(s) S. Thomas Rainfall Intensity taken from the Fort Collins Stormwater Criteria Manual (FCSCM), Tables RA-7 and RA-8 February 17, 2018 Intensity, i10 (in/hr) C10 Q = C f ( C )( i )( A ) 2/17/2018 3:35 PM D:\Projects\911-007\Drainage\Hydrology\911-007_Proposed_Rational_Calcs.xlsx\Runoff (min) 2-yr Tc (min) 10-yr Tc (min) 100-yr Tc (min) A1 A1 No 0.74 0.74 0.92 12 5.22% 1.3 1.3 0.7 N/A N/A N/A 227 0.70% 1.67 2.3 5.0 5.0 5.0 A2 A2 No 0.59 0.59 0.73 41 11.56% 2.7 2.7 1.9 N/A N/A N/A 159 1.39% 2.36 1.1 5.0 5.0 5.0 A3 A3 No 0.57 0.57 0.71 41 17.90% 2.4 2.4 1.8 N/A N/A N/A 124 1.14% 2.13 1.0 5.0 5.0 5.0 A4 A4 No 0.58 0.58 0.72 41 17.85% 2.4 2.4 1.7 N/A N/A N/A 141 1.70% 2.61 0.9 5.0 5.0 5.0 A5 A5 No 0.89 0.89 1.00 65 3.49% 2.1 2.1 1.0 N/A N/A N/A 510 0.84% 1.83 4.6 6.7 6.7 5.6 A6 A6 No 0.67 0.67 0.83 61 5.49% 3.6 3.6 2.2 N/A N/A N/A 74 0.50% 1.41 0.9 5.0 5.0 5.0 A7 A7 No 0.55 0.55 0.69 115 0.72% 12.2 12.2 9.1 54 1.89% 2.06 0.4 N/A N/A N/A 12.6 12.6 9.5 A8 A8 No 0.41 0.41 0.52 116 5.96% 7.6 7.6 6.5 209 1.94% 2.09 1.7 N/A N/A N/A 9.3 9.3 8.1 A8 TOTAL BASIN A No 0.62 0.62 0.78 65 3.49% 4.7 4.7 3.2 208 1.95% 2.09 1.7 881 0.74% 1.72 8.5 14.9 14.9 13.4 B1 B1 No 0.95 0.95 1.00 46 2.91% 1.3 1.3 0.9 N/A N/A N/A 358 0.60% 1.55 3.8 5.2 5.2 5.0 B2 B2 No 0.59 0.59 0.74 40 15.58% 2.4 2.4 1.7 453 1.82% 2.02 3.7 N/A N/A N/A 6.1 6.1 5.4 B3 B3 No 0.83 0.83 1.00 36 3.36% 2.0 2.0 0.7 N/A N/A N/A 398 1.25% 2.23 3.0 5.0 5.0 5.0 B4 B4 No 0.72 0.72 0.90 37 3.70% 2.8 2.8 1.5 N/A N/A N/A 59 2.98% 3.45 0.3 5.0 5.0 5.0 B5 B5 No 0.78 0.78 0.98 11 5.18% 1.1 1.1 0.4 N/A N/A N/A 250 1.76% 2.65 1.6 5.0 5.0 5.0 B6 B6 No 0.50 0.50 0.62 35 1.43% 5.9 5.9 4.7 300 0.58% 1.15 4.4 N/A N/A N/A 10.3 10.3 9.1 B7 B7 No 0.30 0.30 0.38 49 8.14% 5.2 5.2 4.7 195 3.25% 2.70 1.2 64 1.08% 2.08 0.5 6.9 6.9 6.4 B6 TOTAL BASIN B No 0.62 0.62 0.78 35 1.43% 4.7 4.7 3.1 520 1.46% 1.81 4.8 64 1.08% 2.08 0.5 10.0 10.0 8.4 C1 C1 No 0.56 0.56 0.70 33 8.30% 2.8 2.8 2.1 N/A N/A N/A 71 3.86% 3.93 0.3 5.0 5.0 5.0 C2 C2 No 0.39 0.39 0.48 51 6.61% 5.1 5.1 4.4 115 3.03% 2.61 0.7 N/A N/A N/A 5.8 5.8 5.1 C2 TOTAL BASIN C No 0.43 0.43 0.54 51 6.61% 4.8 4.8 4.0 115 3.03% 2.61 0.7 N/A N/A N/A 5.5 5.5 5.0 D1 D1 No 0.95 0.95 1.00 43 2.79% 1.3 1.3 0.9 N/A N/A N/A 255 1.52% 2.47 1.7 5.0 5.0 5.0 D2 D2 No 0.71 0.71 0.89 N/A N/A N/A N/A N/A N/A N/A 368 2.43% 3.12 2.0 5.0 5.0 5.0 D3 D3 No 0.75 0.75 0.94 68 4.37% 3.3 3.3 1.5 217 1.43% 1.79 2.0 N/A N/A N/A 5.3 5.3 5.0 D4 D4 No 0.70 0.70 0.88 18 2.94% 2.2 2.2 1.2 N/A N/A N/A 266 1.00% 2.00 2.2 5.0 5.0 5.0 D5 D5 No 0.42 0.42 0.53 57 6.11% 5.2 5.2 4.4 338 1.52% 1.85 3.0 N/A N/A N/A 8.3 8.3 7.4 D6 D6 No 0.39 0.39 0.48 42 4.60% 5.2 5.2 4.5 294 2.88% 2.54 1.9 N/A N/A N/A 7.1 7.1 6.4 D6 TOTAL BASIN D No 0.64 0.64 0.80 57 6.11% 3.6 3.6 2.3 294 2.88% 2.54 1.9 104 4.09% 4.04 0.4 5.9 5.9 5.0 UD1 UD1 No 0.83 0.83 1.00 165 3.33% 4.4 4.4 1.6 N/A N/A N/A N/A N/A N/A 5.0 5.0 5.0 UD2 UD2 No 0.26 0.26 0.33 87 11.64% 6.5 6.5 5.9 681 0.94% 1.46 7.8 N/A N/A N/A 14.2 14.2 13.7 HT1 HT1 Yes 0.39 0.39 0.49 500 0.60% 35.2 35.2 30.3 302 4.30% 3.11 1.6 N/A N/A N/A 36.8 36.8 32.0 OS1 OS1 No 0.33 0.33 0.41 20 2.00% 5.1 5.1 4.6 2420 2.10% 2.17 18.6 N/A N/A N/A 23.7 23.7 23.2 * Time of Concentrations are calculated for the entire basin and used for both the Impervious and Pervious portions of the basins. PROPOSED TIME OF CONCENTRATION COMPUTATIONS S. Thomas Design Point Sub-Basin Overland Flow Swale Flow Gutter/Pipe Flow Time of Concentration February 17, 2018 (Equation RO-4) ( ) 3 1 1 . 87 1 . 1 * S Ti C Cf L - = 2/17/2018 3:35 PM D:\Projects\911-007\Drainage\Hydrology\911-007_Proposed_Rational_Calcs.xlsx\Tc 100-year Composite Runoff Coefficient Composite % Imperv. A1 1.45 0.39 0.23 0.43 0.20 Clayey | Average 2% to 7% 0.201 0.74 0.74 0.92 65% A2 0.27 0.00 0.06 0.00 0.07 Clayey | Average 2% to 7% 0.138 0.59 0.59 0.73 43% A3 0.23 0.00 0.05 0.00 0.06 Clayey | Average 2% to 7% 0.125 0.57 0.57 0.71 41% A4 0.25 0.00 0.06 0.00 0.06 Clayey | Average 2% to 7% 0.135 0.58 0.58 0.72 42% A5 1.14 0.21 0.35 0.00 0.48 Clayey | Average 2% to 7% 0.097 0.89 0.89 1.00 84% A6 0.34 0.04 0.05 0.00 0.11 Clayey | Average 2% to 7% 0.139 0.67 0.67 0.83 55% A7 0.41 0.00 0.05 0.00 0.12 Clayey | Average 2% to 7% 0.229 0.55 0.55 0.69 39% A8 1.54 0.00 0.12 0.00 0.24 Clayey | Average 2% to 7% 1.179 0.41 0.41 0.52 21% TOTAL BASIN A 5.77 0.64 0.97 0.43 1.34 Clayey | Average 2% to 7% 2.245 0.62 0.62 0.78 50% B1 0.42 0.39 0.03 0.00 0.00 Clayey | Average 2% to 7% 0.000 0.95 0.95 1.00 99% B2 0.62 0.00 0.09 0.00 0.22 Clayey | Average 2% to 7% 0.316 0.59 0.59 0.74 44% B3 1.22 0.33 0.27 0.00 0.41 Clayey | Average 2% to 7% 0.214 0.83 0.83 1.00 77% B4 0.06 0.03 0.01 0.00 0.00 Clayey | Average 2% to 7% 0.019 0.72 0.72 0.90 66% B5 0.19 0.10 0.04 0.00 0.00 Clayey | Average 2% to 7% 0.044 0.78 0.78 0.98 74% B6 0.40 0.00 0.00 0.33 0.00 Clayey | Average 2% to 7% 0.072 0.50 0.50 0.62 33% B7 1.09 0.00 0.00 0.19 0.00 Clayey | Average 2% to 7% 0.899 0.30 0.30 0.38 7% TOTAL BASIN B 3.99 0.84 0.44 0.52 0.62 Clayey | Average 2% to 7% 1.565 0.62 0.62 0.78 50% C1 0.15 0.00 0.03 0.00 0.04 Clayey | Average 2% to 7% 0.086 0.56 0.56 0.70 40% C2 0.48 0.00 0.05 0.00 0.04 Clayey | Average 2% to 7% 0.388 0.39 0.39 0.48 17% TOTAL BASIN C 0.64 0.00 0.08 0.00 0.08 Clayey | Average 2% to 7% 0.474 0.43 0.43 0.54 23% D1 0.25 0.24 0.01 0.00 0.00 Clayey | Average 2% to 7% 0.000 0.95 0.95 1.00 99% D2 1.66 0.46 0.32 0.22 0.22 Clayey | Average 2% to 7% 0.437 0.71 0.71 0.89 62% D3 0.88 0.35 0.14 0.00 0.14 Clayey | Average 2% to 7% 0.250 0.75 0.75 0.94 68% D4 0.65 0.12 0.12 0.30 0.05 Clayey | Average 2% to 7% 0.058 0.70 0.70 0.88 61% D5 0.89 0.00 0.06 0.00 0.16 Clayey | Average 2% to 7% 0.666 0.42 0.42 0.53 22% D6 0.57 0.00 0.02 0.22 0.00 Clayey | Average 2% to 7% 0.331 0.39 0.39 0.48 18% TOTAL BASIN D 4.89 1.17 0.67 0.75 0.57 Clayey | Average 2% to 7% 1.743 0.64 0.64 0.80 53% UD1 0.05 0.03 0.01 0.00 0.00 Clayey | Average 2% to 7% 0.009 0.83 0.83 1.00 80% UD2 4.05 0.00 0.07 0.00 0.00 Clayey | Average 2% to 7% 3.986 0.26 0.26 0.33 2% TOTAL SITE 19.40 2.68 2.24 1.69 2.62 Clayey | Average 2% to 7% 10.021 0.55 0.55 0.68 40% HT1 16.86 0.63 7.71 0.00 0.00 0.00 Clayey | Average 2% to 7% 8.527 0.39 0.39 0.49 22% OS1 14.72 1.47 0.15 0.00 0.00 0.00 Clayey | Average 2% to 7% 13.248 0.33 0.33 0.41 10% Composite Runoff Coefficient with Adjustment PROPOSED COMPOSITE % IMPERVIOUSNESS AND RUNOFF COEFFICIENT CALCULATIONS 2/17/2018 3:34 PM D:\Projects\911-007\Drainage\Hydrology\911-007_Proposed_Rational_Calcs.xlsx\Composite C 3 HB3 Yes 0.25 0.25 0.31 541 0.98% 37.2 37.2 34.5 0 N/A N/A N/A 37.2 37.2 34.5 EXISTING TIME OF CONCENTRATION COMPUTATIONS S. Thomas December 20, 2016 Design Point Sub-Basin Overland Flow Swale Flow Time of Concentration (Equation RO-4) ( ) 3 1 1 . 87 1 . 1 * S Ti C Cf L - = 12/20/2016 3:48 PM D:\Projects\911-007\Drainage\Hydrology\911-007_Existing_Rational_Calcs.xlsx\Tc HA2 4.18 0.00 0.00 0.00 0.00 Clayey | Average 2% to 7% 4.178 0.25 0.25 0.31 0% HA3 0.33 0.15 0.00 0.00 0.00 Clayey | Average 2% to 7% 0.178 0.57 0.57 0.71 45% HB1 5.60 0.00 0.00 0.00 0.00 Clayey | Average 2% to 7% 5.602 0.25 0.25 0.31 0% HB2 0.47 0.21 0.00 0.00 0.00 Clayey | Average 2% to 7% 0.254 0.57 0.57 0.71 45% HB3 4.66 0.00 0.00 0.00 0.00 Clayey | Average 2% to 7% 4.661 0.25 0.25 0.31 0% 1. Table RO-11 | Rational Method Runoff Coefficients for Composite Analysis Composite Runoff Coefficient with Adjustment EXISTING COMPOSITE % IMPERVIOUSNESS AND RUNOFF COEFFICIENT CALCULATIONS 12/20/2016 3:47 PM D:\Projects\911-007\Drainage\Hydrology\911-007_Existing_Rational_Calcs.xlsx\Composite C D3 D3 0.88 0.75 0.94 5.3 5.0 1.88 8.22 D4 D4 0.65 0.70 0.88 5.0 5.0 1.30 5.67 D5 D5 0.89 0.42 0.53 8.3 7.4 0.90 4.13 D6 D6 0.57 0.39 0.48 7.1 6.4 0.56 2.57 UD1 UD1 0.05 0.83 1.00 5.0 5.0 0.12 0.52 UD2 UD2 4.05 0.26 0.33 14.2 13.7 2.04 9.04 HT1 HT1 16.86 0.39 0.49 36.8 32.0 7.50 36.00 OS1 OS1 14.72 0.33 0.41 23.7 23.2 7.06 31.10