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HomeMy WebLinkAboutDrainage Report - sw redlines DRAINAGE REPORT FOR OAK 140 AT 140 EAST OAK STREET FORT COLLINS, CO 80524 PREPARED FOR NOVEMBER 16, 2020 November 16, 2020 Dan Mogen City of Fort Collins Utilities – Stormwater Engineering 700 Wood Street Fort Collins, CO 80521 RE: Oak 140 – Drainage Report JVA Job No. 3258c Dear Dan: The following Drainage Report and attached drainage maps have been prepared for the Oak 140 redevelopment project. The report and drainage maps have been produced in accordance with the City of Fort Collins and the latest local Mile High Flood District recommendations. It is our understanding that the information provided herein meets all requirements of the City of Fort Collins. Please contact us if you have any questions regarding this submission. Sincerely, JVA, Inc. __________________________ Erik T. Nakos, P.E. Project Manager Oak 140 Drainage Report Page 2 of 7 ENGINEER’S STATEMENT: “I hereby certify that this report (plan) for the Drainage Design for the Oak 140 redevelopment was prepared by me (or under my direct supervision) in accordance with the provisions of the City of Fort Collins Standards for the Responsible Parties thereof. I understand that the City of Fort Collins does not and shall not assume liability for drainage facilities designed by others.” ______________________________ Charles R. Hager, IV Registered Professional Engineer State of Colorado No. 37146 Oak 140 Drainage Report Page 3 of 7 GENERAL LOCATION AND EXISTING SITE INFORMATION The Oak 140 (site) is located in Section 12, Township 7 North, Range 69 West of the 6th Principal Meridian, in Larimer County, Fort Collins, Colorado. Refer to Appendix A for the site vicinity map. The site is bordered to the south by E Oak Street, to the east by Remington Street, and to the east by Montezuma Fuller Alley. Developed residential areas are to the north, south, east and west of the site. The existing site, platted as Lots 23-26, 29 and W 33 Ft Lot 30 all in Block 121, FTC (same owner: Fort Collins Downtown Development Authority), is predominantly gravel and asphalt from a previously demolished building. This site is part of the master drainage plan for the Old Town Drainage Basin and designed to conform to the drainage basin design. The site is approximately 0.58 acres of previously developed property and has a historical percent impervious of 92.6%. With the historical building removed years ago, the existing site has less percent imperviousness with a gravel lot, however the drainage design was calculated to the historical site. The existing ground surface is relatively flat, generally sloping to the east at grades ranging from 0.1% to 3.0%. From the geotechnical report dated May 5, 2020 the soil is mainly clayey sand. Groundwater was encountered at 14 ft to 20 ft below the ground surface. The Summary Logs of Exploratory Borings from the geotechnical report is attached in Appendix A. The site is located outside FEMA and City of Fort Collins mapped 100-year and 500-year floodplains, per FEMA Flood Risk Map Number 08069C0979H, effective date 05/02/2012. The site is comprised of hydrologic soil group C/D per NRCS soil survey. The FEMA Firm Map and NRCS Websoil Survey are included in Appendix A. In general, the proposed redevelopment of the site consists of constructing a new building and surrounding hardscape for proposed pedestrian pathways. In the new building, the roof drains will be conveyed to 3rd floor LID planters to be used as LID treatment. Any excess flow will bypass the system through a series of overflows and be conveyed to the public storm system to the south in Oak street. The site development will decrease the overall percent impervious slightly by 1.3% to a total of 91.3% from the historical 92.6%. The Old Town Drainage Basin requirements are that detention is required if there is an increase of impervious area by an additional 5,000 SF from the historical site. Since there is no proposed increase of imperviousness of the site from the historical site, there is no detention required for this project. However, as part of the City of Fort Collins Storm Criteria, there are water quality and LID treatment requirements because the project includes over 1,000 SF of new or modified impervious area. The water quality requirement for the site is fulfilled by the existing Udall water quality facility located to the east of the site by the Cache la Poudre River. The Udall facility is considered to treat 50% of the site’s area. The LID requirement is to treat 50% of the added or modified impervious area. The proposed LID planters on the 3rd floor of the building will treat the proposed roof (not including terrace areas) which will exceed the required 50%, and thus the entire site will be considered treated. Oak 140 Drainage Report Page 4 of 7 DRAINAGE BASINS AND HISTORIC RUNOFF HISTORIC DRAINAGE The existing site consists of one basin. The runoff from the existing site sheet flows to the east through a sidewalk chase and into Remington Street. Then appears to flow north in Remington Street to Mountain Ave and is then captured in the curb inlet on the south side of Mountain Ave, west of Remington St. PROPOSED DRAINAGE Proposed drainage patterns are to remain generally the same as the current but will utilize a LID treatment system for the roof area imperviousness before discharging to the public storm system. The bioretention system will be utilized for low impact development (LID) treatment requirements of the site. With the added or modified imperviousness area for the project being 0.69 acres, the 50% required area to treat is 0.34 acres. With the proposed roof area being treated, 0.37 acres, this project will exceed the City requirement by treating 54% of the added or modified imperviousness. The bioretention systems will reduce runoff, treat and slowly release the water quality capture volume as part of the four step process for the City of Fort Collins criteria on BMP selection. Detention will not be required as we are meeting the planned design outlined in the Old Town Basin Master Drainage Plan and not increasing the site imperviousness as com pared to historical imperviousness. For the purposes of calculations, the site was divided into 5 basins. Basin 1 includes the proposed building roof that is conveyed to the LID planter on the 3 rd floor. Basin 2 consists of the area of the LID planter itself. Basin 3 is the roof area that is not conveyed to the LID planter and is conveyed through combined and conveyed through roof drain overflow. Basin 4 consists of the are within the property line to the north of the building that has modified impervious area. Basin 5 is the area outside the property line that has modified impervious area. The proposed building roof (Basin 1) is draining to the bioretention system (Basin 2) and is joined by the roof drain areas not collected in the LID (Basin 3), then conveyed to the public storm system at the inlet in Oak Street. The surrounding proposed hardscapes (Basins 4 & 5) will drain to either the south in the Oak storm system or to Remington Street as the site has done historically and is not anticipated to have any additional impacts to the surrounding area. A series of 5 area drains and 5 overflow drains will be utilized in the LID planter area, sized by the plumbing engineer per the International Plumbing Code. The lower area drains will allow runoff to be treated and slowly drain the WQ storm while the overflow drains will capture any flows that overflow for events larger up to the 100-yr storm. Events larger than that would overflow onto the deck of the third floor terrace and captured in the overflows drains on the deck and conveyed to discharge on the south side of the building. DRAINAGE DESIGN CRITERIA HYDROLOGIC METHOD AND DESIGN STORM FREQUENCIES The drainage for the site was designed to meet or exceed the City of Fort Collins’s Standards and Specifications, including the Stormwater Criterial Manual which incorporates most of the Mile High Flood District’s (MFHD) Urban Storm Drainage Criteria Manual (USDCM). Oak 140 Drainage Report Page 5 of 7 The design one hour point rainfall used for the 2 year and 100 year storm events are 0.82 inches and 2.86 inches respectively. The Rational Method (Q=CIA) was used to determine the storm runoff (Q) from the areas contributing to the new storm system, with composite runoff coefficients (C) and contributing areas (A) given for design points in sub-basins. The runoff coefficients for various land usages were obtained from FCDCM, Chapter 5. Intensities (I) were determined using the Time-Intensity- Frequency equations, and a calculated Time of Concentration (tc). Hydraulic Criteria. See Appendix B for the runoff coefficient calculations. HYDRAULIC CRITERIA The proposed drainage system has been designed to comply with the City of Fort Collins Stormwater Criteria Manual. The MHFD UD-BMP spreadsheet version 3.07 was used to analyze the designed bioretention. Area drains were sized using MHFD’s USDCM Section 3.3.6 and calculations are included with the rational calculations in Appendix B. Complete drainage plans, details, dimensions, etc. are included in the grading and drainage plans in the site’s construction documents. VARIANCES FROM THE CRITERIA No variances are requested for this design. FOUR STEP PROCESS The Four Step Process implemented by the City of Fort Collins for stormwater quality management is: 1. Reduce runoff through use of Low Impact Development (LID) and Minimizing Directly Connected Impervious Area (MDCIA) 2. Implement BMPs that provide a WQCV with slow release. 3. Stabilize Streams 4. Implement site specific and other source control BMPs. This project is addressing this Four Step Process in the following ways; 1. The reduction of impervious area compared to historical, as well as the use of LID bioretention planters to reduce runoff 2. The use of the LID biorentention system to capture and slow release, as well as the use of the existing Udall facility. 3. There is no negative impact to stream erosion with the development of this site as compared to historical. 4. The trash enclosure is located far away from the storm drainage facilities so that highly polluted runoff has an opportunity to be cleaned prior to runoff in storm drainage. During construction, erosion and sedimentation controls shall be used to prevent the risk of sediment from entering the storm drainage system Oak 140 Drainage Report Page 6 of 7 DRAINAGE FACILITY DESIGN GENERAL CONCEPT The site’s private storm drainage system has been designed to convey the 100-year storm event through a combination of bioretention, inlets and pipes that connect into the existing curb inlet in Oak Street. The hardscape around the building will be graded to drain into the ROW as it has historically done. The existing public system in Oak Street and Remington are assumed to have sufficient capacity for the developed flow as the developed impervious and runoff rates are less than the historical rates. The proposed bioretention planters located on the 3rd floor of the building will treat storm runoff for a minimum of 50% of the modified or added impervious area on the site for water quality treatment prior to discharging into the public storm system, satisfying the City of Fort Collins LID requirements. These features will facilitate sedimentation and filtration while limiting erosion, providing both treatment and slowed release of the water quality capture volume. The proposed redevelopment of this site will serve to limit water quality and quantity impacts to natural drainageways by decreasing the frequency, rate, duration, and volume of runoff. STORMWATER POLLUTION PREVENTION/EROSION CONTROL As site is less than 1 acre of disturbed area, an erosion control report is not required per City of Fort Collins Storm Criteria. However, an erosion control plan and escrow is submitted to meet with City requirements. During construction, temporary erosion and sediment control practices will be used to limit soil erosion and sediment discharge off the site and into public existing stormwater infrastructure. TEMPORARY EROSION CONTROL A temporary erosion control plan is to be implemented for the site during construction. Temporary erosion control measures include, but are not limited to, vehicle tracking control, concrete washout areas, and inlet and slope protection provided using erosion control wattles/sediment control logs, rock socks, etc. All temporary erosion control measures are to be removed after they are deemed unnecessary. A general erosion control plan has been provided in the civil construction documents. PERMANENT EROSION CONTROL Chapter 2 of the Urban Drainage and Flood Control District’s Urban Storm Drainage Criteria Manual Volume 3 (USDCM) provides guidelines for the selection of appropriate permanent structural BMPs for a site that is to be developed or redeveloped. The Oak 140 is best characterized as a “conventional redevelopment” with under 1 acre of impervious area on the project site. The BMP decision tree for such sites is provided in Figure 2 -2 of the USDCM. As previously stated, the site and surrounding vicinity is comprised of hydrologic soil group Type C/D soils, per the NRCS soil survey. The water quality capture volume (WQCV) for this site is accounted for in the existing Udall water quality and detention facility. No detention is required on the site. Runoff will be collected in the private storm system before connecting to the public storm system, or sheet flow into the ROW as it has done historically. The existing storm system should have sufficient capacity for the sites runoff flows as the imperviousness and runoff from the site is less than the historical flows. Oak 140 Drainage Report Page 7 of 7 CONCLUSIONS This Drainage Report for the Oak 140 has been prepared to comply with the stormwater criteria set by the City of Fort Collins and the Mile High Flood Control District. The proposed drainage system presented in this report is designed to convey the 100-year peak stormwater runoff through the site via the proposed and existing storm systems. Through calculations, modeling, and review of the proposed storm drain system, there appears to be adequate capacity to convey the proposed flows to the existing storm system. It can therefore be concluded that development of the Oak 140 complies with all of the stormwater jurisdictional criteria and will not adversely affect the existing streets, storm drain system and/or detention/water quality facilities. REFERENCES 1. City of Fort Collins Stormwater Criteria Manual, City of Fort Collins, December 2018. 2. “Geotechnical Investigation Proposed Apartment Complex, 140 East Oak Street, Fort Collins, Colorado”, CTL Thompson Incorporated, Dated May 5, 2020. 3. “Urban Storm Drainage Criteria Manual”, Mile High Flood District, August 2018 version. 4. FEMA Flood Insurance Rate Map, Map Number 08069C0979H, Map Revised May 2, 2012 5. USDA NRCS Web Soil Survey APPENDIX A – REFERENCED INFORMATION Oak 140 140 East Oak St Fort Collins, CO MAP NOT TO SCALE (Image from Google Earth) 0 5 10 15 20 25 30 35 40 0 5 10 15 20 25 30 35 40 6/12 14/12 50/2 50/1 50/2 50/2 WC=12.4 DD=119 SW=0.0 SS=<0.01 WC=17.7 DD=113 SW=0.1 WC=12.4 DD=119 SW=0.0 SS=<0.01 WC=17.7 DD=113 SW=0.1 TH-1 8/12 50/11 50/8 50/1 50/2 50/2 50/2 WC=15.4 DD=112 LL=34 PI=19 -200=53 WC=2.6 -200=5 WC=15.7 DD=106 -200=20 WC=15.4 DD=112 LL=34 PI=19 -200=53 WC=2.6 -200=5 WC=15.7 DD=106 -200=20 TH-2 6/12 19/12 50/8 50/1 WC=15.0 DD=113 SW=0.1 WC=13.2 DD=117 SW=0.6 WC=8.7 -200=16 WC=15.0 DD=113 SW=0.1 WC=13.2 DD=117 SW=0.6 WC=8.7 -200=16 TH-3 10/12 14/12 50/7 50/2 WC=14.9 DD=115 SW=0.0 WC=11.4 DD=124 -200=30 WC=14.9 DD=115 SW=0.0 WC=11.4 DD=124 -200=30 TH-4 9/12 14/12 50/8 50/1 50/1 50/2 WC=14.5 DD=115 SW=0.0 SS=0.180 WC=12.3 DD=119 SW=0.1 WC=14.5 DD=115 SW=0.0 SS=0.180 WC=12.3 DD=119 SW=0.1 TH-5 DEPTH - FEETDRIVE SAMPLE. THE SYMBOL 6/12 INDICATES 6 BLOWS OF A 140-POUND HAMMER FALLING 30 INCHES WERE REQUIRED TO DRIVE A 2.5-INCH O.D. SAMPLER 12 INCHES. FILL, SAND, CLAYEY WITH OCCASIONAL GRAVEL, MOIST, LOOSE, BROWN, DARK BROWN 1. NOTES: THESE LOGS ARE SUBJECT TO THE EXPLANATIONS, LIMITATIONS AND CONCLUSIONS IN THIS REPORT. WATER LEVEL MEASURED SEVERAL DAYS AFTER DRILLING. SAND, CLAYEY, MOIST, MEDIUM DENSE, BROWN (SC) 3. LEGEND: SAND AND GRAVEL, SLIGHTLY CLAYEY, MOIST TO WET, VERY DENSE, REDDISH BROWN, BROWN (SC, SP, SW-SC, GP) SANDSTONE, CLAYEY, MOIST TO WET, VERY HARD, BROWN, OLIVE DEPTH - FEETWATER LEVEL MEASURED AT TIME OF DRILLING. Summary Logs of Exploratory Borings THE BORINGS WERE DRILLED ON APRIL 24, 2020 USING 4-INCH DIAMETER CONTINUOUS-FLIGHT AUGERS AND A TRUCK-MOUNTED DRILL RIG. FIGURE 2 WC DD SW -200 LL PI UC SS - - - - - - - - INDICATES MOISTURE CONTENT (%). INDICATES DRY DENSITY (PCF). INDICATES SWELL WHEN WETTED UNDER OVERBURDEN PRESSURE (%). INDICATES PASSING NO. 200 SIEVE (%). INDICATES LIQUID LIMIT. INDICATES PLASTICITY INDEX. INDICATES UNCONFINED COMPRESSIVE STRENGTH (PSF). INDICATES SOLUBLE SULFATE CONTENT (%). 2. HOUSING CATALYST 140 EAST OAK STREET CTL | T PROJECT NO. FC09242-125 United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Larimer County Area, ColoradoNatural Resources Conservation Service April 22, 2020 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/ portal/nrcs/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/? cid=nrcs142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 2 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Contents Preface....................................................................................................................2 Soil Map..................................................................................................................5 Soil Map................................................................................................................6 Legend..................................................................................................................7 Map Unit Legend..................................................................................................8 Map Unit Descriptions..........................................................................................8 Larimer County Area, Colorado......................................................................10 35—Fort Collins loam, 0 to 3 percent slopes..............................................10 94—Satanta loam, 0 to 1 percent slopes....................................................11 References............................................................................................................13 4 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 5 6 Custom Soil Resource Report Soil Map 449276544927734492781449278944927974492805449281344928214492829449276544927734492781449278944927974492805449281344928214492829493547 493555 493563 493571 493579 493587 493595 493547 493555 493563 493571 493579 493587 493595 40° 35' 10'' N 105° 4' 34'' W40° 35' 10'' N105° 4' 32'' W40° 35' 8'' N 105° 4' 34'' W40° 35' 8'' N 105° 4' 32'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 15 30 60 90 Feet 0 5 10 20 30 Meters Map Scale: 1:345 if printed on A portrait (8.5" x 11") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features 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: 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 Survey Area Data: Version 14, Sep 13, 2019 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 11, 2018—Aug 12, 2018 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. Custom Soil Resource Report 7 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 35 Fort Collins loam, 0 to 3 percent slopes 0.1 30.9% 94 Satanta loam, 0 to 1 percent slopes 0.3 69.1% Totals for Area of Interest 0.4 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, Custom Soil Resource Report 8 onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha-Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 9 Larimer County Area, Colorado 35—Fort Collins loam, 0 to 3 percent slopes Map Unit Setting National map unit symbol: 2tlnc Elevation: 4,020 to 6,730 feet Mean annual precipitation: 14 to 16 inches Mean annual air temperature: 46 to 48 degrees F Frost-free period: 135 to 160 days Farmland classification: Prime farmland if irrigated Map Unit Composition Fort collins and similar soils: 85 percent Minor components: 15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Fort Collins Setting Landform: Stream terraces, interfluves Landform position (three-dimensional): Interfluve, tread Down-slope shape: Linear Across-slope shape: Linear Parent material: Pleistocene or older alluvium and/or eolian deposits Typical profile Ap - 0 to 4 inches: loam Bt1 - 4 to 9 inches: clay loam Bt2 - 9 to 16 inches: clay loam Bk1 - 16 to 29 inches: loam Bk2 - 29 to 80 inches: loam Properties and qualities Slope: 0 to 3 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.20 to 2.00 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum in profile: 12 percent Salinity, maximum in profile: Nonsaline to very slightly saline (0.1 to 2.0 mmhos/cm) Available water storage in profile: High (about 9.1 inches) Interpretive groups Land capability classification (irrigated): 3e Land capability classification (nonirrigated): 3e Hydrologic Soil Group: C Ecological site: Loamy Plains (R067BY002CO) Hydric soil rating: No Custom Soil Resource Report 10 Minor Components Nunn Percent of map unit: 10 percent Landform: Stream terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across-slope shape: Linear Ecological site: Loamy Plains (R067BY002CO) Hydric soil rating: No Vona Percent of map unit: 5 percent Landform: Interfluves Landform position (three-dimensional): Side slope, interfluve Down-slope shape: Linear Across-slope shape: Linear Ecological site: Sandy Plains (R067BY024CO) Hydric soil rating: No 94—Satanta loam, 0 to 1 percent slopes Map Unit Setting National map unit symbol: 2wz89 Elevation: 3,670 to 5,410 feet Mean annual precipitation: 10 to 23 inches Mean annual air temperature: 45 to 52 degrees F Frost-free period: 105 to 160 days Farmland classification: Prime farmland if irrigated Map Unit Composition Satanta and similar soils: 90 percent Minor components: 10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Satanta Setting Landform: Alluvial fans Landform position (two-dimensional): Backslope Landform position (three-dimensional): Head slope Down-slope shape: Linear Across-slope shape: Linear Parent material: Alluvium Typical profile Ap - 0 to 10 inches: loam Bt - 10 to 17 inches: clay loam C - 17 to 79 inches: loam Custom Soil Resource Report 11 Properties and qualities Slope: 0 to 1 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: Negligible Capacity of the most limiting layer to transmit water (Ksat): Moderately high (0.20 to 0.60 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum in profile: 10 percent Salinity, maximum in profile: Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm) Available water storage in profile: Very high (about 12.3 inches) Interpretive groups Land capability classification (irrigated): 1 Land capability classification (nonirrigated): 2e Hydrologic Soil Group: C Ecological site: Sandy Plains (R072XY111KS) Hydric soil rating: No Minor Components Fort collins Percent of map unit: 5 percent Landform: Alluvial fans Landform position (two-dimensional): Backslope Landform position (three-dimensional): Head slope Down-slope shape: Linear Across-slope shape: Linear Ecological site: Sandy Plains (R072XY111KS) Hydric soil rating: No Nunn Percent of map unit: 5 percent Landform: Terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across-slope shape: Linear Ecological site: Loamy Lowland (R072XY108KS) Hydric soil rating: No Custom Soil Resource Report 12 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 13 United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report 14 54 4982.633 cp elecbox 55 4982.956 cp chase 56 4982.462 cp tbw 57 4981.353 cp drive 4982.240 fnd 108 4982.207 fnd n and s14823 109 4981.346 fnd n and s 112 4981.672 fnd n and s 113 4982.384 fnd n and s383481590 4983.043 inletgrt 1591 4982.992 inletgrt 1592 4982.922 inletgrt 1593 4982.867 inletgrt 1596 4981.879 h2ovalveHYD 1597 4982.240 fh 1598 4981.659 h2ovalve W 1600 4981.737 meterh2o CONTROL IRR 1601 4982.043 irrcvW 1602 4982.250 meterh2o 1603 4982.232 lp 1604 4981.901 sign1 pedxing 1605 4982.567 treed18 1606 4982.417 treed18 1607 4981.376 sign1 2hr prkng 1608 4982.354 sign1 2hr prkng 1609 4982.640 sign1 2hr prkng 1610 4982.973 sign1 2hr prkng W 1611 4983.372 meterh2o CONTROL IRR 1612 4982.854 irrcv1613 4983.803 treed4 1614 4983.618 G 1615 4983.295 metergas G 1616 4983.105 metergas G 2119 4982.822 metergas G 2120 4982.167 metergas ELEC 2121 4982.495 elecboxVAULT CABLE 2122 4982.581 cablevlt 2123 4982.701 inletgrt G 2124 4983.220 metergas G 2125 4983.217 metergas 2126 4983.228 inletgrt AC 2127 4983.019 acunit VAULT ELEC 2128 4982.771 elecvlt ELEC 2129 4985.501 elecbox 2130 4982.479 inletgrt 2131 4983.668 inletgrt 2132 4983.603 inletgrt C 2133 4983.612 pedcable T 2134 4983.185 pedtele VAULT CABLE 2135 4983.230 cablevlt VAULT TELE 2136 4982.882 televlt VAULT ELEC 2137 4982.692 elecvlt 2138 4982.676 inletgrt VAULT ELEC 2139 4982.467 elecvlt 2140 4982.344 lp 2141 4982.437 lp 2142 4982.487 bollard 2143 4982.491 bollardE 2144 4982.654 meterelc ELEC 2145 4982.595 elecbox E 2146 4982.108 meterelc 2147 4981.828 lp 2148 4982.175 bollard 2149 4982.740 column 1.3x1.3 2150 4982.807 column 1.3x1.3 2151 4982.783 column 1.3x1.3 2152 4982.693 column 1.3x1.3 2153 4982.593 column 1.3x1.3 2154 4982.695 column 1.3x1.3 2155 4982.557 column 2.8x2.82156 4982.560 column 2.8x2.8 2157 4982.111 bollard2158 4982.082 bollard 2159 4982.046 bollard 2160 4981.996 bollard 2161 4981.982 bollard ELEC 2162 4983.393 elecbox D 2166 4983.429 mhsan 2167 CONTROL IRR 2168 4982.967 irrcv CONTROL IRR 2169 4982.063 irrcv VAULT ELEC 2171 4980.987 elecvlt C 2172 4981.135 pedcable C S 2177 4981.356 h2ostopFOFOEEEGFOEEEEETTTTTCTVCTVCTVCTV CTVCTVCTVCTVCTVCTVCTVCTVCTVCTVTTTTTTTTTTT TTTTTTTTGGGGG G G G GGGGGGGGIRRIRRIRRIRRIRRIRRIRRIRRIRRIRRIRRFOFOFOFOFOFO0.2'±0.1'±20' ALLEYSSSSSSSSSSSSSSSSSSSSSSSTSTSTSTSTSTSTSTSTSTD 2 4982.354 mhstorm 3 4981.654 inletgrt 4 4981.622 inletgrt 2116 4981.611 inletgrt 2117 4981.535 inletgrt 2118 4981.525 inletgrt 12" PVC257.2 LF 12" PVC @ 1.41%3097 4981.946 postsqr 4x6in 4981.941 postsqr 4x6in3099 4981.927 postsqr 4x6in 4981.466 postsqr 4x6in 3132 4981.501 bollard3133 4981.393 bollard 3134 4981.246 bollard E 3167 4982.064 meterelc ELEC BRKR 3186 4982.379 elecbrkr ELEC BRKR 3187 4982.295 elecbrkr meterelc 9 total 3623 4980.790 h2ovalve h2ostop 2.4' 11.3' 25.2'EWWWWWWWWWWEEEEEETGEEECTV EEEEEEEEEEEETTTTTEEEEEEEEEBASIS OF BEARINGS LOT 23 LOT 24 LOT 25 LOT 26 LOT 27 LOT 28 LOT 29 LOT 30 FND NAIL & BRASS TAG, LS 38348 FND HOLE FOR N&S FND NAIL & BRASS TAG, LS 14823 CP "CHASE" CHISELED "X" IN CONCRETE CP "TBW" CP "ELECBOX" CHISELED "X" IN CONCRETE BUILDING ON OR NEAR PROPERTY LINE BUILDING ON OR NEAR PROPERTY LINE 6' WIDE ELECTRICAL EASEMENT (BOOK 1895, PAGE 353) 20' ACCESS EASEMENT (REC. NO. 97005964) 35' ACCESS EASEMENT (REC. NO. 97001702) ASPHALT ASPHALT - BLOCK 121 - 110 EAST OAK LLC 110 EAST OAK LLC HEWITT JAMES C/ HEWITT JAMES C/ HEWITT FAMILY TRUST 140-2 SOUTH COLLEGE AVENUE LLC KGB HOLDINGS LLC KGB HOLDINGS LLC REMINGTON LLP CP "DRIVE" CHISELED "X" IN CONCRETE N00°19'03"E 200.05'S89°42'21"E 107.00'N89°41'52"W 60.00'S00°19'03"W 50.00'S89°42'27"E 60.00'N89°42'21"W 140.00' 60.1'50.1'60.1'50.2'20.3'0.2'16.5'14.1'8.0'14.1'23.5'4.7'4.6'22.0'S00°19'03"W 25.03'ACCESS EASEMENT (REC. NO. 97005964) (HATCHED AREA) 100.03'WESTCOTT ENTERPRISES LLC FF=4982.49 FF=4984.75 FF=4984.24 FF=4983.25 FF=4984.64 1 STORY BRICKFF=4982.542 HOUR PARKING 2 HOUR PARKING BIKE RACK 2 HOUR PARKING STORM INLET GRATE=4981.61 FL=4977.51 (S) STORM MH RIM=4983.43 INV=4979.25 (N, SW) 11.1 LF 18" RCP @ 0.27% SAN MH RIM=4983.62 INV=4975.77 (N, S) STORM MH RIM=4982.35 INV=4979.43 (N, S) 194.4 LF 18" RCP @ 0.09% HISTORIC PERCENTAGE OF IMPERVIOUSNESS 3258c-140 E. OAK STREET 07-07-2020 1319 Spruce Street Boulder, CO 80302 303.444.1951 www.jvajva.com JVA, Inc. Boulder ● Fort Collins ● Winter Park Glenwood Springs ● Denver HISTORIC PERCENTAGE OF IMPERVIOUSNESS HY D CONTROL IRR W W CONTROL IRR G G G G ELEC VAULT CABLE G G AC VAULT ELEC ELEC C T VAULT CABLE VAULT TELE VAULT ELEC VAULT ELEC E E D CONTROL IRR CONTROL IRR VAULT ELEC C C SFOFOEEEGFOEEEETCTVCTVCTVCTV CTVCTVCTVCTVCTVCTVCTVCTVCTVCTVTTTTTTTTTT TTTTTTGGGGGGGGGGGGIRRIRRIRRIRRIRRIRRIRRIRRIRRIRRIRRFOFOFOFOFOFO20' ALLEYSSSSSSSSSSSSSSSSSSSSSSSTSTSTSTSTSTSTSTSTSTD EELEC BRKR ELEC BRKR 2.4' 11.3' 25.2'EWWWWWWWWWWEEEEEETGEEECTV EEEEEEEEEEEETTTTTEEEEEEEEEEEEBASIS OF BEARINGS FND NAIL & BRASS TAG, LS 38348 FND HOLE FOR N&S FND NAIL & BRASS TAG, LS 14823 CP "CHASE" CHISELED "X" IN CONCRETE CP "TBW" CP "ELECBOX" CHISELED "X" IN CONCRETE 6' WIDE ELECTRICAL EASEMENT (BOOK 1895, PAGE 353) 20' ACCESS EASEMENT (REC. NO. 97005964) 35' ACCESS EASEMENT (REC. NO. 97001702) ASPHALT 110 EAST OAK LLC 110 EAST OAK LLC HEWITT JAMES C/ HEWITT JAMES C/ HEWITT FAMILY TRUST 140-2 SOUTH COLLEGE AVENUE LLC KGB HOLDINGS LLC KGB HOLDINGS LLC REMINGTON LLP CP "DRIVE" CHISELED "X" IN CONCRETE 20.3'0.2'16.5'14.1'8.0'14.1'23.5'4.7'4.6'22.0' WESTCOTT ENTERPRISES LLC FF=4984.75 FF=4984.24 FF=4983.25 FF=4984.64 FF=4982.54BIKE RACK 2 HOUR PARKING 4" WIDE CONCRETE WALL STONE BENCH 6" WIDE CONCRETE STORM INLET GRATE=4981.61 FL=4977.51 (S) STORM MH RIM=4983.43 INV=4979.25 (N, SW) 11.1 LF 18" RCP @ 0.27% SAN MH RIM=4983.62 INV=4975.77 (N, S) STORM MH RIM=4982.35 INV=4979.43 (N, S) 194.4 LF 18" RCP @ 0.09% LOT 23 LOT 24 LOT 25 LOT 26 LOT 27 LOT 28 LOT 29 LOT 30 - BLOCK 121 - DEVELOPED PERCENTAGE OF IMPERVIOUSNESS 3258C-140 E. OAK STREET 11-16-2020 1319 Spruce Street Boulder, CO 80302 303.444.1951 www.jvajva.com JVA, Inc. Boulder ● Fort Collins ● Winter Park Glenwood Springs ● Denver DEVELOPED PERCENTAGE OF IMPERVIOUSNESS HY DCONTROL IRR W W CONTROL IRR G G G G ELEC VAULT CABLE G G AC VAULT ELEC ELEC C T VAULT CABLE VAULT TELE VAULT ELEC VAULT ELEC E E D CONTROL IRR CONTROL IRR D VAULT ELEC C VAULT ELEC CONTROL IRR C SFOFOEEEIRRIRRIRRTTTTGGGGFOEEEETCTVCTVCTVCTV CTVCTVCTVCTVCTVCTVCTVCTVCTVCTVTTTTTTTTTT TTTTTTGGGGGGGGGGGGGIRRIRRIRRIRRIRRIRRIRRIRRIRRIRRIRRFOFOFOFOFOFOFO20' ALLEYEAST OAK STREET (100' PUBLIC R.O.W.)SSSSSSSSSSSSSSSSSSSSSSSSSSSSST ST ST ST ST ST ST ST ST ST ST ST ST STSTSTSTSTSTSTSTSTSTSTSTSTSTD STSTSTELEC ELEC T VAULT TELE C T EELEC BRKR ELEC BRKR E VAULT ELEC D C S EWWWWWWWWWWEEEEW W WWWFOFOFOFOFOGG GGGGGGGGGGEEEEET TGEGEEGT T CTV T T TTEE EEEEEEEEEEEEEEEEETTTTTEEEEEEEEEEEESTSTSTSTSTSTASPHALT 20.3'0.2'16.5'14.1'8.0'14.1'23.5'4.7'51.0'4.6'22.0' LOT 23 LOT 24 LOT 25 LOT 26 LOT 27 LOT 28 LOT 29 LOT 30 - BLOCK 121 -REMINGTON STREET(100' PUBLIC R.O.W.)DRAWING NUMBER: 419 Canyon Ave. Suite 200 Fort Collins, CO 80521 phone 970.224.5828 | fax 970.225.6657 | www.ripleydesigninc.com ■ land planning ■ landscape architecture ■ ■ urban design ■ entitlement ■ ISSUED PROJECT No.: DRAWN BY: REVIEWED BY: SEAL: PREPARED BY: No.DESCRIPTION DATE REVISIONS No.DESCRIPTION DATE Plotted By: Eric J. Kohnen Layout: 24x36 Printed On: 11/16/2020 5:50 PM File Name: 3258c-DPP.dwgORIGINAL SIZE 24X36 ENTI T L E M E N T DRA WI N G S NOT F O R CON S T R U C TI O N RIPLEY DESIGN INC. Katy Thompson 419 Canyon Ave. Suite 200 Fort Collins, CO 80521 p. 970.224.5828 f. 970.225.6657 DOWNTOWN DEVELOPMENT AUTHORITY Matt Robenalt, Executive Director 19 Old Town Square Suite #230 Fort Collins, CO 80524 p. 970.419.4381 ENGINEER DEVELOPER LANDSCAPE ARCHITECT JVA CONSULTING ENGINEERS Erik Nakos 213 Linden Street #200 Fort Collins, CO 80524 p. 970.255.9099 HOUSING CATALYST Kristin Fritz, Chief Real Estate Officer 1715 W Mountain Ave. Fort Collins, CO 80521 p. 970.416.2938 SHOPWORKS ARCHITECTURE Chad Holtzinger 301 W 45th Avenue Denver, CO 80216 p. 303.433.4094 OWNER ARCHITECT OAK 140 FDP SUBMITTAL FORT COLLINS, CO PDP ROUND 1 7-8-2020 R20-001 MEC ETN 01 PDP ROUND 2 7-30-202002 FDP ROUND 1 10-21-202003 FDP ROUND 2 11-17-202004 FIGURE 3 DRAINAGE PLAN APPENDIX B – HYDROLOGIC/HYDRAULIC COMPUTATIONS JVA Incorporated JVA Office: 213 Linden St, S 200 Fort Collins Fort Collins, CO 80524 Ph: (970) 225 9099 Version 2019_XT: 9/3/2019 Project Information: Job Name: Oak 140 Job Number: 3258c Date: 11/18/2020 Designed by: EJK Municipality : Fort_Collins Soil Type: C/D Runoff Calculations: Minor Design Storm: 2 year Major Design Storm: 100 year Detention Calculations: Minor Storm Detention: 10 year plus 100 % WQCV Major Storm Detention: 100 year plus 100 % WQCV Detention Volume by: ≤5ac FAA >5ac FAA+20% Enter WQCV : 0 cf (GB, PP, PLD, SFB, EDB,etc.) Allowable Release Rates (if applicable): Max release rate 1 cfs / acre? Yes Site Area: 0.00 acres Enter Offsite flows to bypass site (these will be added to the allowable release rates) Q10 = 0.00 cfs (bypass flows)Q10allow = 0.00 cfs Q100 = 0.00 cfs (bypass flows)Q100allow = 0.00 cfs Rainfall Data Information: Enter City, Town, or County: Fort_Collins Frequency of Design Event Do you need to Calc P1? No 2 yr 0.82 in 5 yr 1.14 in 10 yr 1.40 in 100 yr 2.86 in Runoff Coefficient Calculations: Use UDFCD Equations? No Intensity Duration Values: I-D-F FortCollinsIDF One Hour Point Rainfall P1 3258c - Rational Calculations INTRO Page 1 of 8 JVA IncorporatedJob Name: Oak 140I% C2 C5 C10 C100213 Linden St, S 200Job Number: 3258cStreets Paved 100% 0.95 0.95 0.95 1.00Fort Collins, CO 80524Date: 11/18/20Concrete Drives/Walks 90% 0.95 0.95 0.95 1.00Ph: (970) 225 9099By: EJKRoof 90% 0.95 0.95 0.95 1.00Gravel 40% 0.50 0.50 0.50 0.63Landscaping (B soil) 2% 0.15 0.15 0.15 0.19Oak 140Landscaping (C/D soil) 2% 0.25 0.25 0.25 0.31Historic Runoff Coefficient & Time of Concentration CalculationsPlayground 10% 0.11 0.11 0.11 0.14Location: Fort_CollinsArtificial Turf 25% 0.20 0.20 0.20 0.25Minor Design Storm: 2Major Design Storm: 100Soil Type: C/DBasin Design DataI (%) = 100% 90% 90% 40% 10% 25% 2% 2%I (%)tc Comptc FinalBasin NameDesign PointApaved streets (sf)Adrives/conc (sf)Aroof (sf)Agravel (sf)Aplygnd (sf)Aart. turf (sf)Alscape (B soil) (sf)Alscape (C/D soil) (sf)ATotal (sf)ATotal (ac)Imp (%)C2 C5 C10 C100Upper most Length (ft)Slope (%)ti (min)Length (ft)Slope (%)Type of Land SurfaceKVelocity (fps) tt (min)Time of Conc ti + tt = tcTotal Length (ft)tc=(L/180)+10 (min.) Min tcH 1 6,505 2,083 16,74325,331 0.58 92.6% 0.95 0.95 0.95 1.00100 1.0%2.8300 1.0%Paved areas & shallow paved swales20 2.0 2.5 5.3 400 12.2 5.30 0.00Paved areas & shallow paved swales20 0 10.00 0.00Paved areas & shallow paved swales20 0 10.00 0.00Paved areas & shallow paved swales20 0 10.00 0.00Paved areas & shallow paved swales20 0 10.0TOTAL SITE 6,505 2,083 16,743 0 0 0 0 0 25,331 0.58 92.6% 0.950.95 0.95 1.00Basin NameDesign PointTime of Conc (tc)C2 C5 C10 C100 2 5 10 100ATotal (sf)ATotal (ac)Q2 Q5 Q10 Q100H 1 5.3 0.95 0.95 0.95 1.00 2.80 0.00 4.78 9.76 25,331 0.58 1.540.00 2.64 5.670 00 0.000 00 0.000 00 0.000 00 0.00TOTAL SITE 25,331 0.58 1.54 0.00 2.64 5.67Initial Overland Time (ti)Travel Time (tt) tt=Length/(Velocity x 60)tc Urbanized Check ONRunoff Coeff's Rainfall Intensities (in/hr)Area Flow Rates (cfs)Runoff Coeff's3258c - Rational CalculationsHistoricPage 2 of 8 JVA Incorporated Job Name: Oak 140 I% C2 C5 C10 C100 213 Linden St, S 200 Job Number: 3258c Streets Paved 100% 0.95 0.95 0.95 1.00 Fort Collins, CO 80524 Date: 11/18/20 Concrete Drives/Walks 90% 0.95 0.95 0.95 1.00 Ph: (970) 225 9099 By: EJK Roof 90% 0.95 0.95 0.95 1.00 Gravel 40% 0.50 0.50 0.50 0.63 Landscaping (B soil) 0% 0.15 0.15 0.15 0.19 Oak 140 Landscaping (C/D soil) 0% 0.25 0.25 0.25 0.31 Composite Runoff Coefficient Calculations Playground 10% 0.11 0.11 0.11 0.14 Location: Fort_Collins Artificial Turf 25% 0.20 0.20 0.20 0.25 Minor Design Storm: 2 Major Design Storm: 100 Soil Type: C/D Basin Design Data I (%) = 100% 90% 90% 40% 10% 25% 0% 0%I (%) Basin Name Design Point Apaved streets (sf) Adrives/c onc (sf) Aroof (sf) Agravel (sf) Aplygnd (sf) Aart. turf (sf) Alscape (B soil) (sf) Alscape (C/D soil) (sf) ATotal (sf) ATotal (ac) Imp (%)C2 C5 C10 C100 1 1 16,966 16,966 0.39 90.0% 0.95 0.95 0.95 1.00 2 2 1,133 1,133 0.03 90.0% 0.95 0.95 0.95 1.00 TOTAL TO LID 0 0 18,099 0 0 0 0 0 18,099 0.42 90.0% 0.95 0.95 0.95 1.00 3 3 3,823 3,823 0.09 90.0% 0.95 0.95 0.95 1.00 4 4 3,061 338 3,399 0.08 99.0% 0.95 0.95 0.95 1.00 PROPERTY TOTAL 3,061 338 21,922 0 0 0 0 0 25,321 0.58 91.2% 0.95 0.95 0.95 1.00 5 5 64 4,522 522 5,108 0.12 80.9% 0.88 0.88 0.88 0.93 PROJECT TOTAL 3,125 4,860 21,922 0 0 0 0 522 30,429 0.70 89.5%0.94 0.94 0.94 0.99 Runoff Coeff's 3258c - Rational Calculations Developed C Page 3 of 8 JVA Incorporated Job Name: Oak 140 213 Linden St, S 200 Job Number: 3258c Fort Collins, CO 80524 Date: 11/18/20 Ph: (970) 225 9099 By: EJK Oak 140 Time of Concentration Calculations Location: Fort_Collins Minor Design Storm: 2 Major Design Storm: 100 Soil Type: C/D Sub-Basin Data tc Comp tc Final Basin Name Design Point ATotal (ac)C5 Upper most Length (ft) Slope (%) ti (min) Length (ft)Slope (%) Type of Land Surface Cv Velocity (fps) tt (min) Time of Conc ti + tt = tc Total Length (ft) tc=(L/180)+ 10 (min) Min tc 1 1 0.39 0.95 80 2.0%2.0 Paved areas & shallow paved swales 20 0.0 0.0 2.0 80 10.4 5.0 2 2 0.03 0.95 5 1.0%0.6 Paved areas & shallow paved swales 20 0.0 0.0 0.6 5 10.0 5.0 3 3 0.09 0.95 45 2.0%1.5 Paved areas & shallow paved swales 20 0.0 0.0 1.5 45 10.3 5.0 4 4 0.08 0.95 33 0.5%2.0 150 1.0% Paved areas & shallow paved swales 20 2.0 1.3 3.2 183 11.0 5.0 5 5 0.12 0.88 20 2.0%1.4 Paved areas & shallow paved swales 20 0.0 0.0 1.4 20 10.1 5.0 Initial Overland Time (ti)Travel Time (tt) tt=Length/(Velocity x 60) tc Urbanized Check ON 3258c - Rational Calculations Developed Tc Page 4 of 8 JVA IncorporatedJob Name: Oak 140213 Linden St, S 200 Job Number: 3258cFort Collins, CO 80524 Date: 11/18/20Ph: (970) 225 9099 By: EJKOak 140LID AREA Calculations per City of Fort CollinsThe implementation of LID systems requires one of the following two options:Acres NotesTotal Project Area = 0.70 Area within the drainage boundaryTotal Project Impervious Area = 0.69 Area of impervious surfacesAdded or Modified Impervious Area = 0.69 Area of impervious surfaces - existing impervious surface areaRequired Impervious Area to be treated by LID=0.3450% of added or modified impervious areaTotal Site Imperv Area to LID = 0.42Provided Treatment Area= 0.37 54%3258c - Rational CalculationsLID AREAPage 5 of 8 JVA IncorporatedJob Name: Oak 140213 Linden St, S 200 Job Number: 3258cFort Collins, CO 80524 Date: 11/18/20Ph: (970) 225 9099 By: EJKOak 140Water Quality Capture Volume (WQCV) Calculations (UDFCD Volume 3 Chapter 3)For LID DesignWQCV=a((0.91I3)-(1.19I2)+(0.78I))Where: WQCV = Water Quality Capture Volume (watershed inches) a = Drain Time Coefficient (see table below ) I = Imperviousness (%/100)Drainage Time (hrs) Coefficient, a12 0.824 0.940 1.00a= 0.80 12 hour drawdown timeI= 0.900 %/100WQCV= 0.322 watershed inchesV=(WQCV/12)*A*43560WQCV= 0.322 watershed inchesA = 0.34 acreV = 481 cf RequiredV = 0.011 acre-ftFort Collins Stormwater Criteria ManualFort Collins Stormwater Criteria Manual3258c - Rational CalculationsWQCVPage 6 of 8 JVA IncorporatedJob Name: Oak 140213 Linden St, S 200Job Number: 3258cFort Collins, CO 80524Date: 11/18/20Ph: (970) 225 9099By: EJKOak 140Developed Storm Runoff CalculationsDesign Storm : 100 YearPoint Hour Rainfall (P1) : 2.86 Basin Name Design Point Area (ac) Runoff Coeff tc (min) C*A (ac) I (in/hr) Q (cfs) Total tc (min) SC*A (ac) I (in/hr) Q (cfs) Inlet Type Q intercepted Q carryover Q bypass Pipe Size (in) or equivalent Pipe Material Slope (%) Pipe Flow (cfs) Max Pipe Capacity (cfs) Length (ft) Velocity (fps) tt (min)Total Time (min) Notes11 0.39 1.00 5.00 0.39 9.95 3.885.00 0.399.95 3.88RD TO LID 3.8822 0.03 1.00 5.00 0.03 9.95 0.265.00 0.039.95 0.26LID5.00 0.429.95 4.13LID UD & AD 4.13 10 in PVC 2.0% 4.14.31 4.90.00 5.0033 0.09 1.00 5.00 0.09 9.95 0.875.00 0.099.95 0.87Overflow RD 0.87 12 in PVC 2.5% 0.97.948 6.20.13 5.135.13 0.509.89 4.98OAK INLET 4.98 12 in PVC 2.0% 5.07.010 5.60.03 5.1644 0.08 1.00 5.00 0.08 9.95 0.785.00 0.089.95 0.7855 0.12 0.93 5.00 0.11 9.95 1.085.00 0.119.95 1.08Pipe Pipe/Swale Travel TimeTOTAL TO LIDTOTAL TO OAK INLETDirect RunoffTotal Runoff Inlets3258c - Rational CalculationsQ100Page 7 of 8 JVA IncorporatedJob Name: Oak 140213 Linden St, S 200Job Number: 3258cFort Collins, CO 80524Date: 11/18/20Ph: (970) 225 9099By: EJKOak 140Developed Storm Runoff CalculationsDesign Storm : 2 YearPoint Hour Rainfall (P1) : 0.82 Basin Name Design Point Area (ac) Runoff Coeff tc (min) C*A (ac) I (in/hr) Q (cfs) Total tc (min) SC*A (ac) I (in/hr) Q (cfs) Inlet Type Q intercepted Q carryover Q bypass Pipe Size (in) or equivalent Pipe Material Slope (%) Pipe Flow (cfs) Max Pipe Capacity (cfs) Length (ft) Velocity (fps) tt (min)Total Time (min) Notes11 0.39 0.95 5.00 0.37 2.85 1.055.00 0.372.85 1.05 RD TO LID1.0522 0.03 0.95 5.00 0.02 2.85 0.075.00 0.022.85 0.07 LID5.00 0.392.85 1.12 LID UD & AD1.1210 in PVC 2.0%1.14.3 14.90.00 5.0033 0.09 0.95 5.00 0.08 2.85 0.245.00 0.082.85 0.24 Overflow RD0.2412 in PVC 2.5%0.27.9 486.20.13 5.135.13 0.482.83 1.35 OAK INLET1.3512 in PVC 2.0%1.47.0 105.60.03 5.1644 0.08 0.95 5.00 0.07 2.85 0.215.00 0.072.85 0.2155 0.12 0.88 5.00 0.10 2.85 0.295.00 0.102.85 0.29Pipe Pipe/Swale Travel TimeTOTAL TO LIDTOTAL TO OAK INLETDirect RunoffTotal Runoff Inlets3258c - Rational CalculationsQ MinorPage 8 of 8 Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia =90.0 % (100% if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio (i = Ia/100)i = 0.900 C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.32 watershed inches (WQCV= 0.8 * (0.91* i3 - 1.19 * i2 + 0.78 * i) D) Contributing Watershed Area (including rain garden area) Area = 18,099 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV =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 =481 cu ft (Only if a different WQCV Design Volume is desired) 2. Basin Geometry A) WQCV Depth (12-inch maximum)DWQCV =6 in B) Rain Garden Side Slopes (Z = 4 min., horiz. dist per unit vertical) Z = 0.00 ft / ft (Use "0" if rain garden has vertical walls) C) Mimimum Flat Surface Area AMin =326 sq ft D) Actual Flat Surface Area AActual =1133 sq ft E) Area at Design Depth (Top Surface Area)ATop =1133 sq ft F) Rain Garden Total Volume VT=519 cu ft (VT= ((ATop + AActual) / 2) * Depth) 3. Growing Media 4. Underdrain System A) Are underdrains provided?1 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 =cu ft iii) Orifice Diameter, 3/8" Minimum DO = in Design Procedure Form: Rain Garden (RG) EJK JVA, Inc. November 18, 2020 Oak 140 140 Oak Street, Fort Collins, CO UD-BMP (Version 3.07, March 2018) Choose One Choose One 18" Rain Garden Growing Media Other (Explain): YES NO UD-BMP_v3.07, RG 11/18/2020, 9:45 AM Sheet 2 of 2 Designer: Company: Date: Project: Location: 5. Impermeable Geomembrane Liner and Geotextile Separator Fabric A) Is an impermeable liner provided due to proximity of structures or groundwater contamination? PROVIDE A 30 MIL (MIN) PVC LINER WITH CDOT CLASS B GEOTEXTILE ABOVE IT. USE THE SAME GEOTEXTILE BELOW THE LINER IF THE SUBGRADE IS ANGULAR 6. Inlet / Outlet Control A) Inlet Control 7. Vegetation 8. Irrigation A) Will the rain garden be irrigated? Notes: Design Procedure Form: Rain Garden (RG) EJK JVA, Inc. November 18, 2020 Oak 140 140 Oak Street, Fort Collins, CO Choose One Choose One Choose One Sheet Flow- No Energy Dissipation Required Concentrated Flow- Energy Dissipation Provided Plantings Seed (Plan for frequent weed control) Sand Grown or Other High Infiltration Sod Choose One YES NO YES NO UD-BMP_v3.07, RG 11/18/2020, 9:45 AM