Loading...
HomeMy WebLinkAboutVOA SENIOR RESIDENCES - FDP200015 - SUBMITTAL DOCUMENTS - ROUND 3 - STORMWATER-RELATED DOCUMENTSFINAL STORMWATER REPORT FOR VOA SENIOR RESIDENCES AT A PORTION OF OUTLOT A, SPRING CREEK FARMS NORTH FORT COLLINS, CO 80525 FOR VOA NATIONAL SERVICES November 18, 2020 November 18, 2020 Wes Lamarque, P.E. City of Fort Collins Utilities - Stormwater Engineering 700 Wood Street Fort Collins, CO 80521 RE: Final Stormwater Report – VOA Senior Residences A portion of Outlot A, Spring Creek Farms North, Fort Collins CO, 80525 JVA No. 3027c Wes: The following Final Stormwater Report and attached drainage maps have been prepared for the above referenced project. The Final Stormwater Report and drainage maps have been produced in accordance with the “City of Fort Collins Standards and Specifications” (Revised 2018). It is our understanding that the information provided herein meets all requirements of the City of Fort Collins. This report is being included as part of the building permit submittal to the City for the referenced project. Please contact us if you have any questions regarding this submission. Sincerely, JVA, Inc. _________________________ Kevin A. Tone, P.E. President _________________________ Chris D. Holmes Design Engineer Engineer’s Statement “I hereby certify that this report for the preliminary drainage design of the VOA Senior Residences project was prepared by me (or under my direct supervision) in accordance with the provisions of the City of Fort Collins Standards and Specifications (Revised 2018) and the Mile High Flood Control District standards, and was designed to comply with the provisions thereof. I understand that the City of Fort Collins does not and shall not assume liability for drainage facilities designed by others.” Kevin A. Tone Registered Professional Engineer State of Colorado No. 28699 FINAL STORMWATER REPORT FOR VOA SENIOR RESIDENCES AT A PORTION OF OUTLOT A, SPRING CREEK FARMS NORTH FORT COLLINS, CO 80525 FOR VOA NATIONAL SERVICES JVA, Inc. Consulting Engineers 1319 Spruce Street Boulder, CO 80302 (303) 444-1951 JVA, Inc. Project No. 3043c November 18, 2020 FINAL STORMWATER REPORT FOR VOA SENIOR RESIDENCES Final Stormwater Report for VOA Senior Residences i TABLE OF CONTENTS 1 – GENERAL LOCATION AND EXISTING SITE INFO ................................................. 1 2 – HISTORIC DRAINAGE ................................................................................... 2 3 – FLOODPLAIN INFORMATION .......................................................................... 3 4 – PROJECT DESCRIPTION ................................................................................ 4 5 – PROPOSED DRAINAGE FACILITIES .................................................................. 5 6 – REFERENCES ............................................................................................... 8 LIST OF FIGURES FIGURE 1 – EXISTING DRAINAGE MAP FIGURE 2 – PROPOSED DRAINAGE MAP APPENDICES APPENDIX A – MAPPING AND INFORMATION APPENDIX B – CALCULATIONS APPENDIX C – PREVIOUS REPORT EXCERPTS FINAL STORMWATER REPORT FOR VOA SENIOR RESIDENCES Final Stormwater Report for VOA Senior Residences 1 1 – GENERAL LOCATION AND EXISTING SITE INFO LOCATION The property is approximately 2.32 acres and is located in the southern portion of Outlot A within the Spring Creek Farms North Major Site, specifically located in the southeast quarter of section 19, township 7 north, range 68 west, of the 6 th prime meridian. A vicinity map of the site is located in Appendix A. The property is located north of East Drake Road and west of Joseph Allen Drive and the nearest major intersection is located two blocks east of the property at East Drake Road and South Timberland Road. The undeveloped site is bordered on the north and south by residential lots, to the west by Parkwood East Subdivision, and by The Trails at Timberline multifamily to the west. The site is currently undeveloped and predominantly consists of grassy open space with an existing detention pond. EXISTING CONDITIONS The existing ground surface is relatively flat, generally sloping from south to north at grades ranging from 0% to 1%. The majority of stormwater runoff is conveyed via surface flow into the existing detention pond which then flows into the public storm drainage system in Joseph Allen Drive via an outlet structure. See Figure 1: Historic Drainage Map. The site is located within Basin OS1 per the Spring Creek Farms North Filing No. 4 Final Drainage and Erosion Control Report. See Figure C-006 Erosion Control Plan & Drainage Exhibit. According to the NRCS soil survey located in Appendix A, the site consists of Nunn clay loam which is classified as hydraulic soil group C. Soils in this group are described as having moderately high runoff potential when thoroughly wet and somewhat restricted water transmission. Final Stormwater Report for VOA Senior Residences 2 2 – HISTORIC DRAINAGE MASTER DRAINAGE BASIN INFO The site is located within the Foothills drainage basin. Adjacent to the property at the Parkwood East Subdivision, the existing pond is proposed to be retrofitted to accommodate the water quality volume. No other improvements to the basin are proposed for the surrounding area. The basin drains from west to east through the use of open channels and a storm sewer system with the final receiving waters being the Fossil Creek Reservoir through an inlet ditch. The basin is mostly developed with commercial and mixed-use residential. Future development is expected to mimic historical. Final Stormwater Report for VOA Senior Residences 3 3 – FLOODPLAIN INFORMATION FLOODPLAIN The site is located outside FEMA and City of Fort Collins mapped 100-year and 500-year floodplains, per FEMA Flood Risk Map Panel number 08069C1000F, effective date 12/19/2006 located in Appendix A. . Final Stormwater Report for VOA Senior Residences 4 4 – PROJECT DESCRIPTION PROPOSED PROJECT In general, the proposed development of the site consists of the proposed VOA National Services building that is approximately 19,000 square feet, an asphalt parking area, an access driveway on Joseph Allen Drive, and an amenity patio on the west side of the proposed building along with new storm infrastructure to facilitate the drainage characteristics of the site. The site is approximately 2.32 acres in size. The undeveloped site is bordered on the north and south by residential lots, to the west by Parkwood East Subdivision, and by The Trails at Timberline multifamily to the west. Final Stormwater Report for VOA Senior Residences 5 5 – PROPOSED DRAINAGE FACILITIES DRAINAGE PATTERNS Proposed drainage patterns are to remain generally the same as the current, but will utilize landscaped areas, inlets and underground storage to capture the majority of runoff before discharging into the detention pond. The underground storage system will utilize StormTech technology for water quality and low impact development treatment. The site is graded as such to meet the City’s requirements of treating 75% of the sites modified or added impervious area. PROPOSED BASINS The site has been divided into six hydrologic basins for analysis. Basin A represents the area draining towards the proposed area inlet on the west side of the proposed building. Basin B represents the western half of the proposed parking lot and will drain towards proposed StormTech chambers. Basins C and D represent areas draining around the building to the east, into a proposed storm sewer pipe and ultimately to the existing detention pond. Basin E represents the eastern half of the proposed parking lot and the northwestern half of the roof and will drain towards the proposed StormTech chambers. Basin F represents the northern portion of the site which includes a portion of the detention pond. Basins A, C and D will utilize grassed swales to collect runoff and also include culverts and storm pipe systems. All basins will eventually convey stormwater to Fossil Creek. PROPOSED DRAINAGE CONCEPT It follows that the proposed improvements will increase the total impervious area of the basin, from 5.1% to 44.8%. This percentage of imperviousness corresponds to a runoff coefficient of 0.63 for the proposed site. Per the Spring Creek Farms North Filing No. 4 Final Drainage and Erosion Control Report, the existing detention pond was sized using a runoff coefficient of 0.7 for Basin OS1. Therefore, the existing detention pond has enough capacity to detain the runoff from the proposed site. The proposed parking lot encroaches slightly into the existing detention pond area on the northwest side of the site. The site will be graded in a way that the volume of the pond is increased from existing conditions. WQCV from the site using Stormtech chambers decreasing volume from the site into the modified pond. See Figure 2: Developed Drainage Map for the drainage basin boundaries and a summary of the existing and proposed impervious areas. Hydrologic and Hydraulic calculations are attached. The existing pond has a maximum storage capacity of 1.535 acre feet with one foot of freeboard. Although the pond was initially sized to treat basin OS1 with a runoff coefficient of 0.7 and the Final Stormwater Report for VOA Senior Residences 6 proposed condition will only produce a runoff coefficient of 0.63 additional volume has been provided. The proposed maximum storage capacity of the existing pond with improvements will be 1.798 acre feet with on foot of freeboard. The increased capacity will meet and exceed the needs of the proposed site as well as the neighboring properties. LOW IMPACT DEVELOPMENT 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 structural BMPs for a site that is to be developed or redeveloped. VOA Senior Housing is best characterized as a “conventional development” with just over 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. The site and surrounding vicinity are comprised of hydrologic soil group Type C & D soils, per the NRCS soil survey. Permeable pavement (with partial or no infiltration) and/or the use of a “green roof”, rain garden, or grass swale/buffer are the recommended runoff reduction practices for this scenario. However, with the proposed configuration of the site underground StormTech Chambers were chosen to perform the LID water quality treatment. The proposed StormTech storm underground chambers located on the private storm system will treat storm runoff for a minimum of 75% of the modified or added impervious area on the site for water quality prior to discharge into the public storm system, satisfying the City of Fort Collins Low Impact Development (LID) requirements. The total impervious area was determined to be approximately 1. 12 acres. The existing impervious area was 0.08 acres, which results in 1.04 acres of added impervious surface area. Therefore, the required treated impervious area is 0.78 acres. The chambers will be designed to treat a minimum of 0.81 acres of the basin’s impervious area which preliminarily includes the parking lot area and a majority of the roof and concrete sidewalk area. The provided chamber sizing worksheet and directions from the City of Fort Collins staff was used to determine that a water quality flow of 0.86 cfs would be directed to the chambers. A restrictor plate on the influent pipe to the chambers will restrict flows to direct the water quality capture volume to the chambers and divert the rest of the flows to the north. The northern diversion pipe invert will be set at the restrictor plate invert elevation. All flows will combine downstream of the chambers before entering the existing outlet structure. The hydraulic capacity of the chambers will be designed to capture and treat the water quality capture volume. The sizing calculations are attached. The chamber design plans will be included with the Final Development Plans. These features will facilitate sedimentation and filtration while limiting erosion, providing both treatment and slowed release of the water quality capture volume. The proposed development of Final Stormwater Report for VOA Senior Residences 7 this site will serve to reduce water quality and quantity impacts to natural drainageways by decreasing the frequency, rate, duration, and volume of runoff. Final Stormwater Report for VOA Senior Residences 8 6 – REFERENCES 1. “Fort Collins Stormwater Criteria Manual,” 2018 Edition. 2. “Urban Storm Drainage Criteria Manual,” Mile High Flood District, updated January 2017. 3. Web Soil Survey, Natural Resources Conservation Service, United State Department of Agriculture, Online at http://websoilsurvey.nrcs.usda.gov, accessed February 25, 2019. 4. FEMA Flood Map Service Center, Online https://msc.fema.gov/portal, accessed February 25, 2019. 5. “Final Drainage and Erosion Control Report for Spring Creek Farms North Filing No. 4”, January 8, 2014. © JVA, Inc. 213 Linden Street, Suite 200 www.jvajva.com Fort Collins, CO 80524 970.225.9099 Boulder ● Fort Collins ● Winter Park Glenwood Springs ● Denver © JVA, Inc. 213 Linden Street, Suite 200 www.jvajva.com Fort Collins, CO 80524 970.225.9099 Boulder ● Fort Collins ● Winter Park Glenwood Springs ● Denver APPENDIX A – MAPPING AND INFORMATION VOA SENIOR RESIDENCES A PORTION OF OUTLOT A, SPRING CREEK FARMS NORTH FORT COLLINS, COLORADO LOCATED IN THE SOUTHEAST QUARTER OF SECTION 19 TOWNSHIP 7 NORTH, RANGE 68 WEST OF THE 6TH PM, CITY OF FORT COLLINS, COUNTY OF LARIMER, STATE OF COLORADO 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 Natural Area, Colorado Resources Conservation Service February 25, 2019 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 How Soil Surveys Are Made..................................................................................5 Soil Map.................................................................................................................. 8 Soil Map................................................................................................................9 Legend................................................................................................................10 Map Unit Legend................................................................................................ 11 Map Unit Descriptions.........................................................................................11 Larimer County Area, Colorado...................................................................... 13 73—Nunn clay loam, 0 to 1 percent slopes.................................................13 References............................................................................................................15 4 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil-landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil-landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and Custom Soil Resource Report 6 identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. Custom Soil Resource Report 7 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. 8 9 Custom Soil Resource Report Soil Map 4489100 4489110 4489120 4489130 4489140 4489150 4489160 4489170 4489180 4489190 4489200 4489100 4489110 4489120 4489130 4489140 4489150 4489160 4489170 4489180 4489190 4489200 496340 496350 496360 496370 496380 496390 496400 496410 496420 496430 496440 496450 496460 496470 496480 496490 496340 496350 496360 496370 496380 496390 496400 496410 496420 496430 496440 496450 496460 496470 496480 496490 40° 33' 12'' N 105° 2' 36'' W 40° 33' 12'' N 105° 2' 29'' W 40° 33' 9'' N 105° 2' 36'' W 40° 33' 9'' N 105° 2' 29'' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 35 70 140 210 Feet 0 10 20 40 60 Meters Map Scale: 1:755 if printed on A landscape (11" x 8.5") 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 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 73 Nunn clay loam, 0 to 1 percent slopes 2.3 100.0% Totals for Area of Interest 2.3 100.0% 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, onsite investigation is needed to define and locate the soils and miscellaneous areas. Custom Soil Resource Report 11 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 12 Larimer County Area, Colorado 73—Nunn clay loam, 0 to 1 percent slopes Map Unit Setting National map unit symbol: 2tlng Elevation: 4,100 to 5,700 feet Mean annual precipitation: 14 to 15 inches Mean annual air temperature: 48 to 52 degrees F Frost-free period: 135 to 152 days Farmland classification: Prime farmland if irrigated Map Unit Composition Nunn and similar soils: 85 percent Minor components: 15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Nunn Setting Landform: Terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across-slope shape: Linear Parent material: Pleistocene aged alluvium and/or eolian deposits Typical profile Ap - 0 to 6 inches: clay loam Bt1 - 6 to 10 inches: clay loam Bt2 - 10 to 26 inches: clay loam Btk - 26 to 31 inches: clay loam Bk1 - 31 to 47 inches: loam Bk2 - 47 to 80 inches: loam Properties and qualities Slope: 0 to 1 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat): Moderately low to moderately high (0.06 to 0.20 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum in profile: 7 percent Salinity, maximum in profile: Nonsaline (0.1 to 1.0 mmhos/cm) Sodium adsorption ratio, maximum in profile: 0.5 Available water storage in profile: High (about 9.1 inches) Interpretive groups Land capability classification (irrigated): 3e Land capability classification (nonirrigated): 4e Hydrologic Soil Group: C Ecological site: Clayey Plains (R067BY042CO) Hydric soil rating: No Custom Soil Resource Report 13 Minor Components Heldt Percent of map unit: 10 percent Landform: Terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across-slope shape: Linear Ecological site: Clayey Plains (R067BY042CO) Hydric soil rating: No Wages Percent of map unit: 5 percent Landform: Terraces Landform position (three-dimensional): Tread Down-slope shape: Linear Across-slope shape: Linear Ecological site: Loamy Plains (R067BY002CO) Hydric soil rating: No Custom Soil Resource Report 14 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 15 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 16 USGS The National Map: Orthoimagery. Data refreshed October, 2017. National Flood Hazard Layer FIRMette 0 250 500 1,000 1,500 2,000 Feet Ü 105°2'51.31"W 40°33'24.07"N 105°2'13.85"W 40°32'56.73"N SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT HAZARD SPECIAL AREAS FLOOD Without Zone A, V, Base A99 Flood Elevation (BFE) With BFE or Depth Zone AE, AO, AH, VE, AR Regulatory Floodway 0.of 2% 1% Annual annual Chance chance Flood flood with Hazard, average Areas depth areasdrainage of less less than than one one foot square or with mile Zone X Future ChanceAnnual Conditions Flood Hazard 1% Zone X Area Levee.to with See Reduced Notes. Flood Risk due Zone X Area with Flood Risk due to LeveeZone D NO SCREEN Area of Minimal Flood Hazard Zone X Area of Undetermined Flood Hazard Zone D Channel, Culvert, or Storm Sewer Levee, Dike, or Floodwall Cross Sections with 1% Annual Chance 17.5 Water Surface Elevation Coastal Transect Coastal Transect Baseline Profile Baseline Hydrographic Feature Base Flood Elevation Line (BFE) Effective LOMRs Limit of Study Jurisdiction Boundary Digital Data Available No Digital Data Available Unmapped This digital map flood complies maps if with it is FEMA's not void standards as described for the below. use of The accuracy basemap standards shown complies with FEMA's basemap The authoritative flood hazard NFHL information web services is derived provided directly by FEMA. from This the map was reflectnot exported changes on or 2/amendments 25/2019 at 11:subsequent 07:04 AM to and this does date and time. becomeor The superseded NFHL and effective by new data information over time. may change This elementsmap map image do not is appear: void if basemap the one or imagery, more of flood the following zone labels, legend, FIRM panel scale number, bar, map and creation FIRM effective date, community date. Map identifiers,images for unmapped regulatoryfor purposes. and unmodernized areas cannot be used Legend OTHER FLOOD AREAS HAZARD OF OTHER AREAS STRGUECNTUERREASL FEATURES OTHER MAP PANELS 8 1:6,000 B 20.2 The point pin selected displayed by the on the user map and is does an approximate not represent an authoritative property location. APPENDIX B – CALCULATIONS JVA Incorporated Job Name: VOA Senior Housing I% C2 C5 C10 C100 213 Linden St, Suite 200 Job Number: 3027c Streets Paved 100% 0.95 0.00 0.95 1.00 Fort Collins, CO 80524 Date: 10/12/20 Concrete Drives/Walks 100% 0.95 0.00 0.95 1.00 Ph: (970) 225 9099 By: MEC Roof 90% 0.95 0.00 0.95 1.00 Gravel 40% 0.50 0.00 0.50 0.63 Landscaping (B soil) 2% 0.15 0.00 0.15 0.19 VOA Senior Housing Landscaping (C/D soil) 2% 0.25 0.00 0.25 0.31 Historic Runoff Coefficient & Time of Concentration Calculations Playground 25% 0.11 0.00 0.11 0.14 Location: Fort_Collins Artificial Turf 25% 0.20 0.00 0.20 0.25 Minor Design Storm: 2 Major Design Storm: 100 Soil Type: C/D Basin Design Data I (%) = 100% 100% 90% 40% 25% 25% 2% 2% I (%) tc Comp tc Final Basin Name Design Point Apaved streets (sf) Adrives/co nc (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 Upper most Length (ft) Slope (%) ti (min) Length (ft) Slope (%) Type of Land Surface K Velocity JVA Incorporated Job Name: VOA Senior Housing I% C2 C5 C10 C100 213 Linden St, Suite 200 Job Number: 3027c Streets Paved 100% 0.95 0.00 0.95 1.00 Fort Collins, CO 80524 Date: 10/12/20 Concrete Drives/Walks 100% 0.95 0.00 0.95 1.00 Ph: (970) 225 9099 By: MEC Roof 90% 0.95 0.00 0.95 1.00 Gravel 40% 0.50 0.00 0.50 0.63 Landscaping (B soil) 2% 0.15 0.00 0.15 0.19 VOA Senior Housing Landscaping (C/D soil) 2% 0.25 0.00 0.25 0.31 Composite Runoff Coefficient Calculations Playground 25% 0.11 0.00 0.11 0.14 Location: Fort_Collins Artificial Turf 25% 0.20 0.00 0.20 0.25 Minor Design Storm: 2 Major Design Storm: 100 Soil Type: C/D Basin Design Data I (%) = 100% 100% 90% 40% 25% 25% 2% 2% 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 A 1 0 3,167 5,397 0 0 0 0 11,111 19,675 0.45 41.9% 0.55 0.00 0.55 0.61 B 2 8,841 735 0 0 0 0 0 933 10,509 0.24 93.5% 0.89 0.00 0.89 0.94 C 3 0 952 5,947 0 0 0 0 12,641 19,540 0.45 32.6% 0.50 0.00 0.50 0.56 D 4 0 1,230 37 0 0 0 0 3,539 4,806 0.11 27.0% 0.43 0.00 0.43 0.49 E 5 13,465 3,047 7,972 0 0 0 0 1,822 26,306 0.60 92.4% 0.90 0.00 0.90 0.95 F 6 0 158 0 0 0 0 0 31,167 31,325 0.72 0.5% 0.25 0.00 0.25 0.32 Property Boundary OA 21,245 9,289 19,353 0 0 0 0 51,350 101,237 2.32 48.6% 0.59 0.00 0.59 0.65 Overall Basin O1 22,306 9,289 19,353 0 0 0 0 61,213 112,161 2.57 44.1% 0.57 0.00 0.57 0.62 Area to Chambers (A,E) 7 22,306 9,289 19,353 0 0 0 0 24,096 75,044 1.72 65.3% 0.73 0.00 0.73 0.78 Runoff Coeff's 3027c - Rational Calculations 040219 Developed C Page 2 of 11 JVA Incorporated Job Name: VOA Senior Housing 213 Linden St, Suite 200 Job Number: 3027c Fort Collins, CO 80524 Date: 10/12/20 Ph: (970) 225 9099 By: MEC VOA Senior Housing 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 A 1 0.45 0.00 50 2.0% 11.3 90 2.0% Paved areas & shallow paved swales 20 2.8 0.5 11.8 140 10.8 10.8 B 2 0.24 0.00 80 2.5% 13.3 10 1.0% Paved areas & shallow paved swales 20 2.0 0.1 13.4 90 10.5 10.5 C 3 0.45 0.00 40 2.0% 10.1 200 2.0% Paved areas & shallow paved swales 20 2.8 1.2 11.3 240 11.3 11.3 JVA Incorporated Job Name: VOA Senior Housing 213 Linden St, Suite 200 Job Number: 3027c Fort Collins, CO 80524 Date: 10/12/20 Ph: (970) 225 9099 By: MEC VOA Senior Housing Developed Storm Runoff Calculations Design Storm : 100 Year Point 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) ΣC*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) Notes A 1 0.45 0.61 10.80 0.28 7.48 2.07 10.80 0.28 7.48 2.07 24" Area Drain 12 in PVC 1.0% 2.07 4.97 105 4.0 0.44 11.24 B 2 0.24 0.94 10.50 0.23 7.57 1.71 10.50 0.23 7.57 1.71 Combination 18 in RCP 1.0% 1.71 11.28 45 4.0 0.19 10.69 TOTAL DS of A 11.24 0.50 7.42 3.73 18 in RCP 1.0% 3.73 11.28 45 4.0 0.19 11.43 C 3 0.45 0.56 11.30 0.25 7.42 1.85 11.30 0.25 7.42 1.85 12 in PVC 1.0% 1.8 5.0 10 4.0 0.04 11.34 D 4 0.11 0.49 5.50 0.05 9.63 0.52 11.43 0.75 7.42 0.57 18 in RCP 1.0% 0.6 11.3 85 4.0 0.36 11.79 TOTAL DS of D 11.79 1.00 7.42 7.43 18 in RCP 1.0% 7.4 11.3 85 4.0 0.36 12.14 E 5 0.60 0.95 10.40 0.58 7.60 4.37 11.43 0.75 7.42 3.64 Combination 18 in RCP 1.0% 3.6 11.3 80 4.0 0.33 11.77 TOTAL DS of E 12.14 1.75 7.37 12.92 12 in PVC 1.0% 12.9 5.0 80 4.0 0.34 12.48 F 6 0.72 0.32 11.40 0.23 7.42 1.69 11.40 0.23 7.42 1.69 Tota Peak Flow 12.48 2.48 7.22 17.93 Tota Site Flow 11.53 Direct Runoff Total Runoff Inlets Pipe Pipe/Swale Travel Time 3027c - Rational Calculations 040219 Q100 Page 4 of 11 JVA Incorporated Job Name: VOA Senior Housing 213 Linden St, Suite 200 Job Number: 3027c Fort Collins, CO 80524 Date: 10/12/20 Ph: (970) 225 9099 By: MEC VOA Senior Housing Developed Storm Runoff Calculations Design Storm : 2 Year Point 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) ΣC*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) A 1 0.45 0.55 10.80 0.25 2.15 0.54 10.80 0.25 2.15 0.54 24" Area Drain 12 in PVC 2.0% 0.54 7.03 56 5.6 0.17 10.97 B 2 0.24 0.89 10.50 0.21 2.17 0.46 10.50 0.21 2.17 0.46 Combination 18 in RCP 0.8% 0.46 10.09 62 3.6 0.29 10.79 TOTAL DS of A 10.97 0.46 2.14 0.99 18 in RCP 2.0% 0.99 15.95 56 5.6 0.17 11.13 C 3 0.45 0.50 11.30 0.22 2.11 0.47 11.30 0.22 2.11 0.47 12 in PVC 0.9% 0.5 4.8 25 3.8 0.11 11.41 D 4 0.11 0.43 5.50 0.05 2.76 0.13 11.13 0.69 2.12 0.14 18 in RCP 1.2% 0.1 12.2 151 4.3 0.59 11.72 TOTAL DS of D 11.72 0.91 2.07 1.89 18 in RCP 1.2% 1.9 12.2 151 4.3 0.59 12.30 E 5 0.60 0.90 10.40 0.54 2.18 1.19 11.13 0.69 2.12 0.99 Combination 18 in RCP 3.7% 1.0 21.6 26 7.6 0.06 11.19 12.30 1.60 2.03 3.24 12 in PVC 3.7% 3.2 9.5 26 7.6 0.06 12.36 F 6 0.72 0.25 11.40 0.18 2.10 0.38 11.40 0.18 2.10 0.38 Tota Peak Flow 12.36 2.25 2.03 4.56 Tota Site Flow 2.98 Direct Runoff Total Runoff Inlets Pipe Pipe/Swale Travel Time 3027c - Rational Calculations 040219 Q Minor Page 5 of 11 JVA Incorporated Job Name: VOA Senior Housing 213 Linden St, Suite 200 Job Number: 3027c Fort Collins, CO 80524 Date: 10/12/20 Ph: (970) 225 9099 By: MEC VOA Senior Housing LID AREA Calculations per City of Fort Collins - Option 2 The implementation of LID systems requires one of the following two options: Acres Notes Total Site Area = 2.57 Area within the drainage boundary Total Site Impervious Area = 1.17 Area of impervious surfaces Added or Modified Impervious Area = 1.09 Area of impervious surfaces - existing impervious surface area Required Impervious Area to be treated by LID = 0.82 75% of added or modified impervious area Total Site Area to Chambers = 1.72 Provided Impervious Area to LID = 1.17 3027c - Rational Calculations 040219 LID AREA Page 6 of 11 Eastern Stormtech Capture Basin JVA Incorporated Job Name: VOA Senior Housing 213 Linden St, Suite 200 Job Number: 3027c Fort Collins, CO 80524 Date: 11/13/20 Ph: (970) 225 9099 By: MEC VOA Senior Housing Water Quality Capture Volume (WQCV) Calculations (UDFCD Volume 3 Chapter 3) WQCV=a((0.91I 3 )-(1.19I 2 )+(0.78I)) Where: WQCV = Water Quality Capture Volume (watershed inches) a = Drain Time Coefficient (see table below ) I = Imperviousness (%/100) Drainage Time (hrs) Coefficient, a 12 0.8 24 0.9 40 1.00 a= 0.80 12 hour drawdown time I= 0.653 %/100 WQCV= 0.205 watershed inches V=(WQCV/12)*A*43560 WQCV= 0.205 watershed inches A = 0.92 acre V = 821 cf V = 0.019 acre-ft Fort Collins Stormwater Criteria Manual Fort Collins Stormwater Criteria Manual 3027c - Rational Calculations 040219 WQCV Page 7 of 11 Western Stormtech Capture Basin JVA Incorporated Job Name: VOA Senior Housing 213 Linden St, Suite 200 Job Number: 3027c Fort Collins, CO 80524 Date: 11/13/20 Ph: (970) 225 9099 By: MEC VOA Senior Housing Water Quality Capture Volume (WQCV) Calculations (UDFCD Volume 3 Chapter 3) WQCV=a((0.91I 3 )-(1.19I 2 )+(0.78I)) Where: WQCV = Water Quality Capture Volume (watershed inches) a = Drain Time Coefficient (see table below ) I = Imperviousness (%/100) Drainage Time (hrs) Coefficient, a 12 0.8 24 0.9 40 1.00 a= 0.80 12 hour drawdown time I= 0.653 %/100 WQCV= 0.205 watershed inches V=(WQCV/12)*A*43560 WQCV= 0.205 watershed inches A = 0.80 acre V = 714 cf V = 0.016 acre-ft Fort Collins Stormwater Criteria Manual Fort Collins Stormwater Criteria Manual 3027c - Rational Calculations 040219 WQCV (2) Page 7 of 11 Eastern Stormtech Capture Basin JVA Incorporated Job Name: VOA Senior Housing 213 Linden St, Suite 200 Job Number: 3027c Fort Collins, CO 80524 Date: 11/13/20 Ph: (970) 225 9099 By: MEC VOA Senior Housing StormTech Chamber Sizing Calculation (per City of Fort Collins Example) 1 2 3 4 5 6 7 8 9 10 11 12 Vault ID Total Required WQ Volume (cf) Flow, WQ (cfs) Chamber Type Chamber Release Rate a (cfs) Chamber Volume b (cf) Installed Chamber Volume w/ Aggregate c (cf) Minimum No. of Chambers d Total Release Rate e (cfs) Required Storage Volume by FAA Method (cf) Minimum No. of Chambers f Storage Provided within the Chambers g (cf) Total Installed System Volume h (cf) Option 1 821 #N/A SC-160 0.011 6.85 15.0 55 0.63 484 71 486 1065 Option 2 821 #N/A SC-310 0.016 14.7 29.3 29 0.46 659 45 662 1319 Option 3 821 #N/A SC-740 0.024 45.9 74.9 11 0.26 504 11 505 824 a. Release rate per chamber, limited by flow through geotextile with accumulated sediment b. Volume within chamber only, not accounting for void spaces in surrounding aggregate c. Volume includes chamber and void spaces (40%) in surrounding aggregate, per chamber unit d. Number of chambers required to provide full WQCV within total installed system, including aggregate. e. Release rate per chamber times number of chambers. Westerm Stormtech Capture Basin JVA Incorporated Job Name: VOA Senior Housing 213 Linden St, Suite 200 Job Number: 3027c Fort Collins, CO 80524 Date: 11/13/20 Ph: (970) 225 9099 By: MEC VOA Senior Housing StormTech Chamber Sizing Calculation (per City of Fort Collins Example) 1 2 3 4 5 6 7 8 9 10 11 12 Vault ID Total Required WQ Volume (cf) Flow, WQ (cfs) Chamber Type Chamber Release Rate a (cfs) Chamber Volume b (cf) Installed Chamber Volume w/ Aggregate c (cf) Minimum No. of Chambers d Total Release Rate e (cfs) Required Storage Volume by FAA Method (cf) Minimum No. of Chambers f Storage Provided within the Chambers g (cf) Total Installed System Volume h (cf) Option 1 714 #N/A SC-160 0.011 6.85 15.0 48 0.55 484 71 486 1065 Option 2 714 #N/A SC-310 0.016 14.7 29.3 25 0.39 659 45 662 1319 Option 3 714 #N/A SC-740 0.024 45.9 74.9 10 0.24 455 10 459 749 a. Release rate per chamber, limited by flow through geotextile with accumulated sediment b. Volume within chamber only, not accounting for void spaces in surrounding aggregate c. Volume includes chamber and void spaces (40%) in surrounding aggregate, per chamber unit d. Number of chambers required to provide full WQCV within total installed system, including aggregate. e. Release rate per chamber times number of chambers. Project: Basin ID: Depth Increment = 0.50 ft Watershed Information Top of Micropool -- 0.00 -- -- -- 124 0.003 Selected BMP Type = EDB -- 0.50 -- -- -- 2,865 0.066 747 0.017 Watershed Area = 10.67 acres -- 1.00 -- -- -- 6,627 0.152 3,120 0.072 Watershed Length = 1,200 ft -- 1.50 -- -- -- 10,515 0.241 7,406 0.170 Watershed Length to Centroid = 500 ft -- 2.00 -- -- -- 14,950 0.343 13,772 0.316 Watershed Slope = 0.025 ft/ft -- 2.50 -- -- -- 20,851 0.479 22,722 0.522 Watershed Imperviousness = 55.00% percent -- 3.00 -- -- -- 21,185 0.486 33,231 0.763 Percentage Hydrologic Soil Group A = 0.0% percent -- 3.50 -- -- -- 29,132 0.669 45,810 1.052 Percentage Hydrologic Soil Group B = 0.0% percent -- 4.00 -- -- -- 32,389 0.744 61,191 1.405 Percentage Hydrologic Soil Groups C/D = 100.0% percent -- 4.50 -- -- -- 36,142 0.830 78,323 1.798 Target WQCV Drain Time = 40.0 hours -- 5.00 -- -- -- 39,914 0.916 97,337 2.235 Location for 1-hr Rainfall Depths = User Input -- 5.50 -- -- -- 43,994 1.010 118,314 2.716 -- -- -- -- -- -- -- -- Optional User Overrides -- -- -- -- Water Quality Capture Volume (WQCV) = 0.196 acre-feet acre-feet -- -- -- -- Excess Urban Runoff Volume (EURV) = 0.559 acre-feet acre-feet -- -- -- -- 2-yr Runoff Volume (P1 = 0.82 in.) = 0.358 acre-feet 0.82 inches -- -- -- -- 5-yr Runoff Volume (P1 = 1.09 in.) = 0.533 acre-feet inches -- -- -- -- 10-yr Runoff Volume (P1 = 1.4 in.) = 0.784 acre-feet 1.40 inches -- -- -- -- 25-yr Runoff Volume (P1 = 1.69 in.) = 1.073 acre-feet inches -- -- -- -- 50-yr Runoff Volume (P1 = 1.99 in.) = 1.340 acre-feet inches -- -- -- -- 100-yr Runoff Volume (P1 = 2.86 in.) = 2.166 acre-feet 2.86 inches -- -- -- -- 500-yr Runoff Volume (P1 = 3.14 in.) = 2.424 acre-feet inches -- -- -- -- Approximate 2-yr Detention Volume = 0.342 acre-feet -- -- -- -- Approximate 5-yr Detention Volume = 0.527 acre-feet -- -- -- -- Approximate 10-yr Detention Volume = 0.662 acre-feet -- -- -- -- Approximate 25-yr Detention Volume = 0.752 acre-feet -- -- -- -- Approximate 50-yr Detention Volume = 0.814 acre-feet -- -- -- -- Approximate 100-yr Detention Volume = 1.171 acre-feet -- -- -- -- -- -- -- -- Define Zones and Basin Geometry -- -- -- -- Select Zone 1 Storage Volume (Required) = acre-feet -- -- -- -- Select Zone 2 Storage Volume (Optional) = acre-feet -- -- -- -- Select Zone 3 Storage Volume (Optional) = acre-feet -- -- -- -- Total Detention Basin Volume = acre-feet -- -- -- -- Initial Surcharge Volume (ISV) = user ft 3 -- -- -- -- Initial Surcharge Depth (ISD) = user ft -- -- -- -- Total Available Detention Depth (Htotal) = user ft -- -- -- -- Depth of Trickle Channel (HTC) = user ft -- -- -- -- Slope of Trickle Channel (STC) = user ft/ft -- -- -- -- Slopes of Main Basin Sides (Smain) = user H:V -- -- -- -- Basin Length-to-Width Ratio (RL/W) = user -- -- -- -- -- -- -- -- Initial Surcharge Area (AISV) = user ft 2 -- -- -- -- Surcharge Volume Length (LISV) = user ft -- -- -- -- Surcharge Volume Width (WISV) = user ft -- -- -- -- Depth of Basin Floor (HFLOOR) = user ft -- -- -- -- Length of Basin Floor (LFLOOR) = user ft -- -- -- -- Width of Basin Floor (WFLOOR) = user ft -- -- -- -- Area of Basin Floor (AFLOOR) = user ft 2 -- -- -- -- Volume of Basin Floor (VFLOOR) = user ft 3 -- -- -- -- Depth of Main Basin (HMAIN) = user ft -- -- -- -- Length of Main Basin (LMAIN) = user ft -- -- -- -- Width of Main Basin (WMAIN) = user ft -- -- -- -- Area of Main Basin (AMAIN) = user ft 2 -- -- -- -- Volume of Main Basin (VMAIN) = user ft 3 -- -- -- -- 1 User Defined Stage-Area Booleans for Message 1 Equal Stage-Area Inputs Watershed L:W 1 CountA Watershed Lc:L Watershed Slope 0 Calc_S_TC Booleans for CUHP 1 CUHP Inputs Complete H_FLOOR 1 CUHP Results Calculated L_FLOOR_OTHER 0.00 ISV 0.00 ISV 0.00 Floor #N/A #N/A #N/A Zone 1 #N/A #N/A 0.00 Zone 2 #N/A #N/A 0.00 Zone 3 #N/A #N/A DETENTION BASIN STAGE-STORAGE TABLE BUILDER MHFD-Detention, Version 4.03 (May 2020) 0.000 0.680 1.360 2.040 2.720 0.000 0.255 0.510 0.765 1.020 0.00 1.50 3.00 4.50 6.00 Volume (ac-ft) Area (acres) Stage (ft.) Area (acres) Volume (ac-ft) 0 11000 22000 33000 44000 0 5 10 15 20 0.00 1.50 3.00 4.50 6.00 Area (sq.ft.) Length, Width (ft.) Stage (ft) Length (ft) Width (ft) Area (sq.ft.) MHFD-Detention_v4 03 (1)_Modified Pond, Basin 10/12/2020, 9:57 AM Project: Basin ID: Depth Increment = 0.50 ft Watershed Information Top of Micropool -- 0.00 -- -- -- 124 0.003 Selected BMP Type = EDB -- 0.50 -- -- -- 2,710 0.062 709 0.016 Watershed Area = 10.67 acres -- 1.00 -- -- -- 5,175 0.119 2,680 0.062 Watershed Length = 1,200 ft -- 1.50 -- -- -- 7,637 0.175 5,883 0.135 Watershed Length to Centroid = 500 ft -- 2.00 -- -- -- 11,555 0.265 10,681 0.245 Watershed Slope = 0.025 ft/ft -- 2.50 -- -- -- 15,950 0.366 17,557 0.403 Watershed Imperviousness = 55.00% percent -- 3.00 -- -- -- 21,061 0.483 26,810 0.615 Percentage Hydrologic Soil Group A = 0.0% percent -- 3.50 -- -- -- 25,014 0.574 38,328 0.880 Percentage Hydrologic Soil Group B = 0.0% percent -- 4.00 -- -- -- 28,356 0.651 51,671 1.186 Percentage Hydrologic Soil Groups C/D = 100.0% percent -- 4.50 -- -- -- 32,420 0.744 66,865 1.535 Target WQCV Drain Time = 40.0 hours -- 5.00 -- -- -- 36,798 0.845 84,169 1.932 Location for 1-hr Rainfall Depths = User Input -- 5.50 -- -- -- 41,832 0.960 103,827 2.384 -- -- -- -- -- -- -- -- Optional User Overrides -- -- -- -- Water Quality Capture Volume (WQCV) = 0.196 acre-feet acre-feet -- -- -- -- Excess Urban Runoff Volume (EURV) = 0.559 acre-feet acre-feet -- -- -- -- 2-yr Runoff Volume (P1 = 0.82 in.) = 0.358 acre-feet 0.82 inches -- -- -- -- 5-yr Runoff Volume (P1 = 1.09 in.) = 0.533 acre-feet inches -- -- -- -- 10-yr Runoff Volume (P1 = 1.4 in.) = 0.784 acre-feet 1.40 inches -- -- -- -- 25-yr Runoff Volume (P1 = 1.69 in.) = 1.073 acre-feet inches -- -- -- -- 50-yr Runoff Volume (P1 = 1.99 in.) = 1.340 acre-feet inches -- -- -- -- 100-yr Runoff Volume (P1 = 2.86 in.) = 2.166 acre-feet 2.86 inches -- -- -- -- 500-yr Runoff Volume (P1 = 3.14 in.) = 2.424 acre-feet inches -- -- -- -- Approximate 2-yr Detention Volume = 0.342 acre-feet -- -- -- -- Approximate 5-yr Detention Volume = 0.527 acre-feet -- -- -- -- Approximate 10-yr Detention Volume = 0.662 acre-feet -- -- -- -- Approximate 25-yr Detention Volume = 0.752 acre-feet -- -- -- -- Approximate 50-yr Detention Volume = 0.814 acre-feet -- -- -- -- Approximate 100-yr Detention Volume = 1.171 acre-feet -- -- -- -- -- -- -- -- Define Zones and Basin Geometry -- -- -- -- Select Zone 1 Storage Volume (Required) = acre-feet -- -- -- -- Select Zone 2 Storage Volume (Optional) = acre-feet -- -- -- -- Select Zone 3 Storage Volume (Optional) = acre-feet -- -- -- -- Total Detention Basin Volume = acre-feet -- -- -- -- Initial Surcharge Volume (ISV) = user ft 3 -- -- -- -- Initial Surcharge Depth (ISD) = user ft -- -- -- -- Total Available Detention Depth (Htotal) = user ft -- -- -- -- Depth of Trickle Channel (HTC) = user ft -- -- -- -- Slope of Trickle Channel (STC) = user ft/ft -- -- -- -- Slopes of Main Basin Sides (Smain) = user H:V -- -- -- -- Basin Length-to-Width Ratio (RL/W) = user -- -- -- -- -- -- -- -- Initial Surcharge Area (AISV) = user ft 2 -- -- -- -- Surcharge Volume Length (LISV) = user ft -- -- -- -- Surcharge Volume Width (WISV) = user ft -- -- -- -- Depth of Basin Floor (HFLOOR) = user ft -- -- -- -- Length of Basin Floor (LFLOOR) = user ft -- -- -- -- Width of Basin Floor (WFLOOR) = user ft -- -- -- -- Area of Basin Floor (AFLOOR) = user ft 2 -- -- -- -- Volume of Basin Floor (VFLOOR) = user ft 3 -- -- -- -- Depth of Main Basin (HMAIN) = user ft -- -- -- -- Length of Main Basin (LMAIN) = user ft -- -- -- -- Width of Main Basin (WMAIN) = user ft -- -- -- -- Area of Main Basin (AMAIN) = user ft 2 -- -- -- -- Volume of Main Basin (VMAIN) = user ft 3 -- -- -- -- 1 User Defined Stage-Area Booleans for Message 1 Equal Stage-Area Inputs Watershed L:W 1 CountA Watershed Lc:L Watershed Slope 0 Calc_S_TC Booleans for CUHP 1 CUHP Inputs Complete H_FLOOR 1 CUHP Results Calculated L_FLOOR_OTHER 0.00 ISV 0.00 ISV 0.00 Floor #N/A #N/A #N/A Zone 1 #N/A #N/A 0.00 Zone 2 #N/A #N/A 0.00 Zone 3 #N/A #N/A DETENTION BASIN STAGE-STORAGE TABLE BUILDER MHFD-Detention, Version 4.03 (May 2020) 0.000 0.600 1.200 1.800 2.400 0.000 0.245 0.490 0.735 0.980 0.00 1.50 3.00 4.50 6.00 Volume (ac-ft) Area (acres) Stage (ft.) Area (acres) Volume (ac-ft) 0 10500 21000 31500 42000 0 5 10 15 20 0.00 1.50 3.00 4.50 6.00 Area (sq.ft.) Length, Width (ft.) Stage (ft) Length (ft) Width (ft) Area (sq.ft.) MHFD-Detention_v4 03 (1)_Existing Pond, Basin 8/4/2020, 3:18 PM APPENDIX C – PREVIOUS REPORT EXCERPTS This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA This unofficial copy was downloaded on Oct-22-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact City of Fort Collins Utilities 700 Wood Street Fort Collins, CO 80524 USA Calculated Total Basin Volume (Vtotal) = user acre-feet -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- After providing required inputs above including 1-hour rainfall depths, click 'Run CUHP' to generate runoff hydrographs using the embedded Colorado Urban Hydrograph Procedure. Volume (ft 3) Volume (ac-ft) Area (acre) DETENTION BASIN STAGE-STORAGE TABLE BUILDER Optional Override Area (ft 2) Length (ft) Optional Override Stage (ft) Stage (ft) Stage - Storage Description Area (ft 2) Width (ft) VOA Senior Housing Existing Detention Pond MHFD-Detention, Version 4.03 (May 2020) ExampleZone Configuration (Retention Pond) MHFD-Detention_v4 03 (1)_Existing Pond, Basin 8/4/2020, 3:18 PM Calculated Total Basin Volume (Vtotal) = user acre-feet -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- After providing required inputs above including 1-hour rainfall depths, click 'Run CUHP' to generate runoff hydrographs using the embedded Colorado Urban Hydrograph Procedure. Volume (ft 3) Volume (ac-ft) Area (acre) DETENTION BASIN STAGE-STORAGE TABLE BUILDER Optional Override Area (ft 2) Length (ft) Optional Override Stage (ft) Stage (ft) Stage - Storage Description Area (ft 2) Width (ft) VOA Senior Housing Modified Detention Pond MHFD-Detention, Version 4.03 (May 2020) ExampleZone Configuration (Retention Pond) MHFD-Detention_v4 03 (1)_Modified Pond, Basin 10/12/2020, 9:57 AM f. Number of chambers required to provide required storage volume stored within the chamber only (no aggregate storage). g. Volume provided in chambers only (no aggregate storage). This number must meet or exceed the required storage volume. h. System volume includes total number of chambers, plus surrounding aggregate. This number must meet or exceed the required WQCV. *Allowable flow rate thru fabric considering rate is reduced by sedimentation between Isolator Row cleanings 3027c - Rational Calculations 040219 CHAMBER SIZING (2) Page 8 of 11 f. Number of chambers required to provide required storage volume stored within the chamber only (no aggregate storage). g. Volume provided in chambers only (no aggregate storage). This number must meet or exceed the required storage volume. h. System volume includes total number of chambers, plus surrounding aggregate. This number must meet or exceed the required WQCV. *Allowable flow rate thru fabric considering rate is reduced by sedimentation between Isolator Row cleanings 3027c - Rational Calculations 040219 CHAMBER SIZING Page 8 of 11 D 4 0.11 0.00 20 5.0% 5.3 30 2.0% Paved areas & shallow paved swales 20 2.8 0.2 5.5 50 10.3 5.5 E 5 0.60 0.00 60 2.5% 11.5 10 1.0% Paved areas & shallow paved swales 20 2.0 0.1 11.6 70 10.4 10.4 F 6 0.72 0.00 70 5.0% 9.9 275 2.3% Paved areas & shallow paved swales 20 3.0 1.5 11.4 345 11.9 11.4 Property Boundary Total Site OA 2.32 0.00 Paved areas & shallow paved swales 20 0.0 0.0 0.0 0 10.0 5.0 Overall Basin O1 2.57 0.00 Paved areas & shallow paved swales 20 0.0 0.0 0.0 0 10.0 5.0 Area to Chambers (A,E) 7 1.72 0.00 70 2.5% 12.4 10 1.0% Paved areas & shallow paved swales 20 2.0 0.1 12.5 80 10.4 10.4 Initial Overland Time (ti ) Travel Time (tt ) tt =Length/(Velocity x 60) tc Urbanized Check ON 3027c - Rational Calculations 040219 Developed Tc Page 3 of 11 (fps) tt (min) Time of Conc ti + tt = tc Total Length (ft) tc=(L/180)+ 10 (min.) Min tc OS1 1 0 3,532 0 0 0 0 0 109,512 113,044 2.60 5.1% 0.27 0.00 0.27 0.33 137 1.0% 23.6 201 4.4% Short Pasture and lawns 7 1.5 2.3 25.9 338 11.9 11.9 TOTAL SITE 0 3,532 0 0 0 0 0 109,512 113,044 2.60 5.1% 0.27 0.00 0.27 0.33 Basin Name Design Point Time of Conc (tc) C2 C5 C10 C100 2 5 10 100 ATotal (sf) ATotal (ac) Q2 Q5 Q10 Q100 OS1 1 11.9 0.27 0.00 0.27 0.33 2.06 0.00 3.63 7.42 113,044 2.60 1.45 0.00 2.56 6.43 TOTAL SITE 113,044 2.60 1.45 0.00 2.56 6.43 Initial Overland Time (ti) Travel Time (tt) tt=Length/(Velocity x 60) tc Urbanized Check ON Runoff Coeff's Rainfall Intensities (in/hr) Area Flow Rates (cfs) Runoff Coeff's 3027c - Rational Calculations 040219 Historic Page 1 of 11 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 13, Sep 10, 2018 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Sep 20, 2015—Oct 21, 2017 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 10