HomeMy WebLinkAboutCIRCLE C ADULT RESIDENTIAL SERVICES - PDP190009 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTCOLORADO CIVIL GROUP, INC.
PRELIMINARY DRAINAGE REPORT
FOR THE
CIRCLE C - ADULT RESIDENTIAL
TREATMENT SERVICES
CITY OF FORT COLLINS
JULY 2019
July 3, 2019
Mr. Shane Boyle, Civil Engineer
Water Utilities Engineering
City of Fort Collins Utilities
700 Wood Street
Fort Collins, CO 80521
Re: Circle C - Adult Residential Treatment Services
Project No. 0060.0002.00
Dear Mr. Boyle,
We are pleased to submit this Preliminary Drainage Report for the Circle C - Adult Residential
Treatment Services located at the corner of Patton, East Elizabeth, and McHugh Streets. This
report was prepared based on the City of Fort Collins Stormwater Criteria Manual adopted in
December 2018.
Please let me know if you have any questions or comments.
Sincerely,
COLORADO CIVIL GROUP, INC.
Edward J. Jansury Jr., PE
Circle C - Adult Residential Treatment Services Preliminary Drainage Report July 2019
COLORADO CIVIL GROUP, INC. • 2204 Hoffman Drive • Loveland, Colorado 80538 • 970-278-0029
COMPLIANCE STATEMENT
I hereby attest that this report for the preliminary drainage design for the Circle C - Adult
Residential Treatment Services was prepared by me or under my direct supervision, in
accordance with the provisions of the Fort Collins Stormwater Criteria Manual. I understand
that the City of Fort Collins does not and will not assume liability for drainage facilities designed
by others.
___________________________
Edward J. Jansury Jr., PE
Registered Professional Engineer
State of Colorado No. 50799
Circle C - Adult Residential Treatment Services Preliminary Drainage Report July 2019
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Table of Contents
1 Project Summary ...................................................................................................................................................... 1
1.1 Site Location ..................................................................................................................................................... 1
1.2 Existing Site Conditions .................................................................................................................................... 2
1.3 Master Drainage Plan Description .................................................................................................................... 2
1.4 Floodplain Information ..................................................................................................................................... 3
1.5 Project Description ........................................................................................................................................... 3
2 Proposed Drainage Facilities .................................................................................................................................... 4
2.1 General Flow Patterns ...................................................................................................................................... 4
2.2 On-Site Basin Description ................................................................................................................................. 4
2.3 On-Site Basin Description ................................................................................................................................. 5
2.4 Water Quantity Detention ................................................................................................................................ 6
2.5 Water Quality Capture Volume ...................................................................................................................... 10
2.6 Maintenance Access ....................................................................................................................................... 12
2.7 Easements ...................................................................................................................................................... 12
3 Proposed Drainage Design Criteria ......................................................................................................................... 12
3.1 Drainage Studies ............................................................................................................................................. 12
3.2 Four-Step Process ........................................................................................................................................... 12
3.2.1 Step 1: Runoff Reduction ........................................................................................................................ 12
3.2.2 Step 2: Treat and Slowly Release Runoff ................................................................................................ 13
3.2.3 Step 3: Stabilize Drainageways ............................................................................................................... 13
3.2.4 Step 4: Implementation of Source Controls ........................................................................................... 13
3.3 BMP Selection Considerations ........................................................................................................................ 13
3.3.1 Soils ......................................................................................................................................................... 13
3.3.2 Watershed Size ....................................................................................................................................... 14
3.3.3 Base Flows .............................................................................................................................................. 14
3.4 BMP Design ..................................................................................................................................................... 14
3.5 Hydrologic Criteria .......................................................................................................................................... 14
4 Variance Requests .................................................................................................................................................. 15
5 Erosion Control ....................................................................................................................................................... 15
6 Conclusions ............................................................................................................................................................. 15
7 References .............................................................................................................................................................. 15
8 Appendices ............................................................................................................................................................. 15
Appendix A: Existing Soil Properties ................................................................................................................................. A
Appendix B: BMP Sizing and Hydrology Calculations ...................................................................................................... B
Circle C - Adult Residential Treatment Services Preliminary Drainage Report July 2019
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Appendix C: Erosion Control Plan and Drainage Plan ..................................................................................................... C
Appendix D: SDI Data Sheet ............................................................................................................................................. D
Index of Figures and Tables
Figure 1-1: Vicinity Map.................................................................................................................................................... 1
Figure 1-2: Spring Creek Drainage Basin .......................................................................................................................... 3
Figure 2-1: Off-Site Basins ................................................................................................................................................ 6
Table 2-1: FCSCM Runoff Coefficients .............................................................................................................................. 7
Table 2-2: FCSCM Frequency Adjustment Factors ........................................................................................................... 8
Table 2-3: Existing Condition Basin Summary .................................................................................................................. 8
Table 2-4: Proposed Condition Basin Summary ............................................................................................................... 8
Table 2-5: Detention Pond Summary Table ..................................................................................................................... 9
Table 2-6: LID Treatment ................................................................................................................................................ 11
Figure 2-2: LID Exhibit ..................................................................................................................................................... 11
Circle C - Adult Residential Treatment Services Preliminary Drainage Report July 2019
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1 Project Summary
1.1 Site Location
The Circle C - Adult Residential Treatment Services site is Lot 2 of the East Elizabeth
Subdivision and is in the Southwest Quarter of Section 18, Township 7 North, Range
68 West of the 6th Principal Meridian, City of Fort Collins, County of Larimer, Colorado.
The site is bounded on the north by East Elizabeth Street, on the west by Patton
Street, on the northeast by McHugh Street and on the south by property owned by
Hanlon Bush Investments, LLC. A vicinity map is presented in Figure 1-1. The project
area is generally located at 40° 34’26” North Latitude and 105° 3’14” West
Longitude.
Figure 1-1: Vicinity Map
E ELIZABETH ST
PATTON ST
PROJECT
AREA
S LEMAY AVE
E PITKIN ST
RIVERSIDE AVE
UCHEALTH
POUDRE
VALLEY
HOSPITAL
MCHUGH ST
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1.2 Existing Site Conditions
The parcel contains 0.635 acres in area as in currently undeveloped with a natural
grass groundcover. The parcel in located in the Spring Creek Drainage Basin. The
soils on site are listed as Kim Loam with 1-3% slopes on the National Resources
Conservation Service Web Soil Survey website. Kim Loam soils are considered well
drained and in Hydrologic Soil Group B. This soils on this site are in wind erodibility
group 4L on a scale of 1 to 8 with group 1 being the most susceptible to wind
erosion. Groundwater depths were found to be 16 feet deep per the geotechnical
report prepared by Earth Engineering Company, Inc.
1.3 Master Drainage Plan Description
As previously mentioned, this site is located within the Spring Creek Drainage Basin
and is part of the Spring Creek Master Drainage Plan. The Spring Creek drainage
basins encompasses approximately 9 square miles. Spring Creek flows from the
Spring Canyon Dam at Horsetooth Reservoir to the Poudre River. This site is in the
northeast corner of the basin in an area where the water quality was not evaluated as
the runoff drains into an existing irrigation system. See Figure 1-2 below and
Appendix A. The area surrounding this site is fully developed with no known master
planning improvements at or near this site.
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Figure 1-2: Spring Creek Drainage Basin
1.4 Floodplain Information
The project site is located within Zone‘X’ of Community-Panel Number 08069C0983H,
revised May 2, 2012. Zone‘X’is defined as “Areas determined to be outside the
0.2% annual chance floodplain.” A portion of the referenced map can be found in
Appendix A of this report.
1.5 Project Description
The Circle C - Adult Residential Treatment Services project includes the complete
development of one parcel (8718312002). This parcel contains 0.635 acres. A building,
parking, and walkways will be built on the currently undeveloped lot. The construction
on this site include an entrance from McHugh Street, an exit onto Patton Street for
emergency and service vehicles, walkways, and an underground detention pond.
PROJECT AREA
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2 Proposed Drainage Facilities
2.1 General Flow Patterns
The site and surrounding properties were reviewed to determine existing drainage
patterns. Runoff generally flows from a high point near the center of the southern
edge of the property westerly and northerly to Patton, E. Elizabeth and McHugh
Streets. Runoff travels northerly along the flow line of Patton Street to its’ intersection
with E. Elizabeth Street and then easterly and southeasterly along the flow line of E.
Elizabeth and McHugh Streets. Off-site flow from a portion of the property south of this
site developed as a rehabilitation and nursing center enters in two locations near the
southeast corner of the site and flows undetained overland northerly to McHugh Street.
No drainage report is available for this adjacent property. Based on the aerial photo,
off-site basins have been delineated and assumptions have been made about slope
based on the slope on Circle C property. Developed drainage basins were delineated
based on existing and proposed improvements. The Final Drainage Plan is in Appendix
C. Three on-site basins and two off-site basins were delineated. Descriptions of the
delineated basins are listed below. The physical parameters and hydraulic calculations
for the basins can be found in Appendix B.
2.2 On-Site Basin Description
Basin A consists of sidewalks and landscape areas between the north and west sides
of the building and the rights-of-way of Patton, E. Elizabeth, and McHugh Streets. The
basin boundary runs along the street right-of-way, per City of Fort Collins direction.
Basin A flows via sheet flow to Patton, East Elizabeth, and McHugh Streets without
detention.
Basin B consists of the proposed commercial building, courtyard area, the majority of
the parking lot pavement, concrete walks, and landscaped area. From the existing
condition to the proposed condition, the imperviousness for the basin is increased by
replacing the natural grass area with parking lot pavement, buildings, and concrete
walks. The basin drains to the StormTech system which then releases flow to a
proposed storm drain prior to outflowing on McHugh Street through the sidewalk chase.
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Basin C includes a portion of an existing commercial parking lot which will provide
access to the site and a portion of landscaped area. Runoff from Basin C flows via
sheet flow to McHugh Street without detention.
2.3 On-Site Basin Description
Basin OS-1 includes a portion of the nursing center property drains to on-site Basin B.
The flows from this basin are accounted for in the storm drain sizing and are conveyed
through the property to McHugh Street undetained.
Basin OS-2 includes the remaining portion of the nursing center property that drains to
the Circle C property drains to on-site Basin C. As no drainage facilities are proposed
for Basin C, runoff from this basin passes through the site and enters McHugh Street
undetained, which is consistent with the existing drainage pattern. Figure 2-1 presents
the delineation of the off-site basins and Appendix B presents the hydrologic
calculations for the basins.
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Figure 2-1: Off-Site Basins
2.4 Water Quantity Detention
In order to determine the quantity of stormwater detention and treatment necessary for the
project site, the existing and proposed conditions were calculated and compared. Surface
Type Runoff Coefficients (Cx) found in Table 3.2.2 of the Fort Collins Stormwater Criteria
Manual (FCSCM) adopted in December 2018 were utilized to determine the composite runoff
coefficients of each basin. Values from this table are presented in Table 2-1 below.
E ELIZABETH ST
PATTON ST
MCHUGH ST
PROJECT
AREA
BASIN
OS-1 BASIN
OS-2
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Table 2-1: FCSCM Runoff Coefficients
Source: Table 3.2.2 Fort Collins Stormwater Criteria Manual, December 2018
Composite coefficients were determined utilizing Equation 5-2 found in the Fort Collins
Stormwater Criteria Manual (FCSCM) adopted in December 2018.
Where: C = Composite Runoff Coefficient
Ci = Runoff Coefficient for Specific Area (Ai), dimensionless
Ai = Area of Surface with Runoff Coefficient of Ci, acres or square feet
n = Number of different surfaces to be considered
At = Total Area over which C is applicable, acres or square feet
The composite runoff coefficients were adjusted by applying frequency adjustment factors (Cf)
for the appropriate design storm event. Composite coefficients Frequency Adjust Factors
found in Table 3.2-3 of the Fort Collins Stormwater Criteria Manual (FCSCM) adopted in
December 2018 utilized are presented in Table 2-2 below.
Hardscape or Hard Surface
Asphalt, Concrete 0.95
Rooftop 0.95
Recycled Asphalt 0.80
Gravel 0.50
Pavers 0.50
Landscape or Pervious Surface
Lawns, Sandy Soil, Flat Slope <2% 0.10
Lawns, Sandy Soil, Avg Slope 2%-7% 0.15
Lawns, Sandy Soil, Steep Slope >7% 0.20
Lawns, Clayey Soil, Flat Slope <2% 0.20
Lawns, Clayey Soil, Avg Slope 2%-7% 0.25
Lawns, Clayey Soil, Steep Slope >7% 0.35
Surface Type Runoff Coefficient (Cx)
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Table 2-2: FCSCM Frequency Adjustment Factors
Source: Table 3.2-3 Fort Collins Stormwater Criteria Manual, December 2018
The adjusted composite runoff coefficient value was determined utilizing the following
equation.
C=Cx*Cf
Maximum adjusted composite runoff coefficient value is limited to 1.00.
The existing condition represents the current project site with no improvements or changes.
The proposed condition represents the project site with the proposed improvements. Basin
categories and area computations can be found in Appendix B. Tables 2-3 and 2-4 below
provide a summary of the existing and proposed basin characteristics.
Table 2-3: Existing Condition Basin Summary
Table 2-4: Proposed Condition Basin Summary
2, 5, 10 1.00
25 1.10
50 1.20
100 1.25
Storm Return Period (years)
Frequency
Adjustment Factor (Cf)
Design Point 100-Year 2-Year 100-Year
I100 Q2 Q100
(acres) (minutes) (in./hour) (in./hour) (ft3/s) (ft3/s)
A 1 0.54 11.9 0.10 0.13 2.1 7.4 0.12 0.50
B 2 0.05 5.0 0.95 1.00 2.9 10.0 0.12 0.45
2-Year
C2
Basin
Area
Rainfall Intensity Runoff
2-Year
I2
Runoff Coefficients
100-Year
C100
Basin I.D.
Time of
Concentration
100-Year 2-Year 100-Year
I100 Q2 Q100
(acres) (minutes) (in./hour) (in./hour) (ft3/s) (ft3/s)
A 0.12 8.6 0.34 0.43 2.4 8.4 0.10 0.44
B 0.41 5.0 0.86 1.00 2.9 10.0 1.00 4.08
C 0.06 5.0 0.74 0.92 2.9 10.0 0.12 0.51
Runoff Coefficients Rainfall Intensity Runoff
2-Year
C2
100-Year
C100
2-Year
I2
Basin I.D.
Basin
Area
Time of
DesignConcentration Point
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Water quantity detention is required for the Circle C - Adult Residential Treatment Services.
During a meeting about the project, the City of Fort Collins staff indicated that due to
existing conditions on site flows from Basins A and C could be released from the site
without detention. Basin A is primarily a landscaped area. Basin C contains the existing
parking lot, which currently drains to the street without detention.
Runoff from Basin B enters the StormTech system before being released to the street. The
StormTech system detention pond has been sized using the Modified FAA Method equations
found in Chapter 6 of the FCSCM. The water quantity detention required was determined to
be 4594 cubic feet or 0.105 acre-feet. Adding the water quantity detention required to the
Water Quality Volume, as required by the FCSCM, results in a detention pond total volume
of 5276 cubic feet or 0.121 acre-feet. The IDF data and detention pond calculations can be
found in Appendix B.
A small area, approximately 900 square feet, located south of the proposed parking lot to
the southerly boundary was included in Basin B calculations. This landscaped area, due to
grades, will combine with the off-site flow from OS1 prior to entering the storm drain which
will convey it to the outfall on McHugh Street.
The StormTech system will utilize SC-310 chambers, has a proposed volume of 5325 cubic
feet, and release at the 2-yr Historic rate of 0.12 cfs. This will be accomplished using an
orifice plate in the StormTech system outlet structure.
Table 2-5: Detention Pond Summary Table
Detention
Pond
Water
Quantity
Volume
Water
Quality
Capture
Volume
Total
Required
Volume
Proposed
System
Volume
Release
Rate
CF CF CF CF CFS
B 4594 682 5276 5325 0.12
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2.5 Water Quality Capture Volume
Equations in Chapter 7 of the FCSCM were used for the calculation of Water Quality
Capture Volume (WQCV) required for the Circle C - Adult Residential Treatment Services
project and are presented below.
The Water Quality Capture Volume is calculated based on the imperviousness of the project
site and the drain time. Most of the new impervious area on the Circle C - Adult
Residential Treatment Services project site will drain to the StormTech system. The most
conservative drain time presented in the FCSCM, 40 hours, has been used in the sizing
calculations for the Circle C - Adult Residential Treatment Services.
The WQCV is calculated based on the imperviousness of the project site and the drain time.
Most of the new impervious area on the Circle C - Adult Residential Treatment Services
project site will drain to the StormTech system. The most conservative drain time presented
in the FCSCM, 40 hours, has been used in the sizing calculations for the Circle C - Adult
Residential Treatment Services.
WQCV = a(0.91I 3-1.19I 2+0.78I) Equation 7-1 FCSCM
Where: WQCV = Water Quality Capture Volume (watershed inches)
a = Drain Time Coefficient (1.0 for a drain time of 40 hours)
I = Imperviousness, %/100 (0.88 for Basin B)
For the Circle C - Adult Residential Treatment Services, the resulting WQCV is 0.382
watershed inches.
The FCSCM uses the WQCV above to find the basin storage volume based on the following
equation:
V = (WQCV/12)*A*1.2 Equation 7-2 FCSCM
Where: V = Basin Design Volume (cubic feet)
WQCV = Water Quality Capture Volume (watershed inches)
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A = Area of Watershed Tributary to the Basin (square feet)
With a total tributary area of 17,844 square feet, the Basin Design Volume required is 682
cubic feet or 0.016 acre-feet.
The City of Fort Collins LID ordinance requires that for 75% of all newly added or modified
impervious areas be treated by LID techniques. Runoff from a small portion of the new or
modified impervious area on the project site flows directly to McHugh Street and is therefore
not treated by the StormTech system. Table 2-6 shows how the LID requirements have
been met for this project. Figure 2-2 shows the location of the StormTech system.
Table 2-6: LID Treatment
Figure 2-2: LID Exhibit
PROJECT AREA
TOTAL NET NEW IMPERVIOUS AREA 16,438 SF
REQUIRED MINIMUM AREA TO BE TREATED BY LID
(75% OF NEW IMPERVIOUS AREA) 12,328 SF
NET NEW IMPERVIOUS AREA TREATED BY LID 15,643 SF
PERCENT OF NEW IMPERVIOUS AREA TREATED BY LID 95%
75% ON-SITE TREATMENT BY LID
STORMTECH
SYSTEM
LID TREATMENT
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2.6 Maintenance Access
The drainage facilities on this site will be privately maintained.
2.7 Easements
A 10-foot-wide drainage easement will be granted to the property owner to the south to
allow for off-site conveyance through the property.
3 Proposed Drainage Design Criteria
3.1 Drainage Studies
There are no available previous drainage studies for this site or the site to the south.
Storm runoff from the property to the south has been analyzed and accounted for as
part of the design for this site.
3.2 Four-Step Process
This section of the report presents the design of drainage facilities related to Circle C -
Adult Residential Treatment Services project. The drainage design has been explained
as it pertains to the “Four-Step Process for Stormwater Quality Management” as
outlined in the FCSCM.
3.2.1 Step 1: Runoff Reduction
The first step in stormwater quality management is to reduce runoff peaks,
volumes, and pollutant loads from urbanizing areas by implementing Low Impact
Development (LID) strategies. LID practices include reducing unnecessary
impervious areas and routing runoff from impervious surfaces over permeable
areas to slow runoff and promote infiltration.
The Circle C - Adult Residential Treatment Services project includes an increase
in impervious area with the construction of the building, concrete walks and
asphalt drives. Runoff from most of the new impervious areas will be routed
through a StormTech detention system. The Isolator Row in the StormTech
system acts as a LID practice by allowing sediment to collect as stormwater
infiltrates through the cloth barrier into the StormTech detention system.
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3.2.2 Step 2: Treat and Slowly Release Runoff
After reducing the runoff from a site, the second step in stormwater quality
management is to capture and slowly release a Water Quality Capture Volume
(WQCV). WQCV facilities may include bioretention, extended detention basins,
sand filters, constructed wetland ponds, and retention ponds.
The StormTech detention system is designed to capture and release the WQCV
for the Circle C - Adult Residential Treatment Services site. The WQCV drain
time for the site is 40 hours.
3.2.3 Step 3: Stabilize Drainageways
Although steps 1 and 2 help to minimize the effects of runoff on downstream
drainageways, natural drainageways are often subject to bed and bank erosion
due to increases in the frequency, rate, duration, and volume of runoff. Step 3
includes measures to prevent drainageway erosion.
There are no drainageways on the Circle C - Adult Residential Treatment
Services site. By implementing steps 1 and 2, the project site does its part to
reduce drainageway erosion downstream.
3.2.4 Step 4: Implementation of Source Controls
The final step in stormwater quality management is source control. Site specific
needs such as material storage or other site operations require consideration of
targeted source control Best Management Practices (BMPs). These BMPs are
shown on the Erosion Control Plan (Appendix C) and explained in the Erosion
Control Report (ECR) for the project site.
3.3 BMP Selection Considerations
The following sections discuss the considerations for determining the best BMP or LID
solution to implement for the project.
3.3.1 Soils
The existing soil condition on the project site must be considered when designing
BMPs. Soils with good permeability provide opportunities for infiltration of runoff
Circle C - Adult Residential Treatment Services Preliminary Drainage Report July 2019
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and are well-suited for infiltration based BMPs such as dry wells, permeable
pavement, and grass swales. The soils on the Circle C - Adult Residential
Treatment Services site are in Hydrologic Soil Group B, which is defined as soils
having a moderate infiltration when thoroughly wet. For this reason, infiltration
based BMPs were considered a good option for the project site. Soil information
for the site may be found in Appendix A.
3.3.2 Watershed Size
The contributing drainage area is an important consideration for the design of
BMPs. For a small site, such as Circle C - Adult Residential Services
Treatment, it is not feasible to design a detention pond that releases the WQCV
over a 40-hour drain time due to the small orifices that would be required.
Instead, it is recommended that small watersheds use filtering BMPs, such as the
StormTech system designed for the project site.
3.3.3 Base Flows
BMPs such as constructed wetlands ponds, retention ponds, and wetland
channels require a base flow to prevent the BMPs from becoming dry and
unable to support wetland vegetation. No base flow exists for the Circle C -
Adult Residential Treatment Services site, so no BMPs that require a base flow
were considered for the site.
3.4 BMP Design
The StormTech chamber system utilizes infiltration to reduce the transportation of
pollutants to downstream receiving waters. The system is equipped with an “isolator
row” which consists of wrapping the row of chambers that takes the first flush of storm
runoff with fabric. This row captures the sediment which can be removed and
disposed of as part of the maintenance process.
3.5 Hydrologic Criteria
Per City of Fort Collins criteria, the Rational Formula Method was used for the
hydrologic analysis of the Circle C - Adult Residential Treatment Services project site.
The rainfall intensities (IDF Data) from the FCSCM were used for the calculation of
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runoff for the 2-year and 100-year storm events. The IDF Data can be found in
Appendix B. Detention Volumes were determined utilizing the Modified FAA procedure
as described in Chapter 6 of the FCSCM.
4 Variance Requests
No variance requests are anticipated with this project.
5 Erosion Control
This project complies with the City of Fort Collins Erosion Control Criteria. All Erosion
Control Materials will be provided with the Final Drainage Report.
6 Conclusions
The final drainage design for the Circle C - Adult Residential Treatment Services project, as
outlined in this Drainage Report, is in compliance with City of Fort Collins Stormwater
Criteria Manual, Master Drainage Plans, Floodplain Regulations, and/or State and Federal
Regulations. The design safely and effectively collects and conveys runoff per the applicable
criteria and mimics existing drainage patterns where possible.
7 References
• City of Fort Collins Stormwater Criteria Manual adopted December 2018
• Advanced Drainage Systems Inc. design criteria for StormTech Chamber Systems
8 Appendices
Appendix A contains the Soil Survey Information, Floodplain Map, and Spring Creek Basin
Management Proposed Condition BMP Map.
Appendix B contains the hydrologic calculations, detention basin – volume calculations, water
quality capture volume calculations, IDF Data, LID Calculations and LID Exhibit.
Appendix C contains the Historic and Proposed Drainage Basin Plans
Appendix D contains the SDI Data Sheet.
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A
Appendix A: Existing Soil Properties
United States
Department of
Agriculture
A product of the National
Cooperative Soil Survey,
a joint effort of the United
States Department of
Agriculture and other
Federal agencies, State
agencies including the
Agricultural Experiment
Stations, and local
participants
Custom Soil Resource
Report for
Larimer County
Area, Colorado
Circle C - Adult Residential
Treatment Services
Natural
Resources
Conservation
Service
June 27, 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
53—Kim loam, 1 to 3 percent slopes.......................................................... 13
Soil Information for All Uses...............................................................................15
Soil Properties and Qualities.............................................................................. 15
Soil Erosion Factors........................................................................................15
Wind Erodibility Group.................................................................................15
Soil Qualities and Features.............................................................................18
Hydrologic Soil Group................................................................................. 18
Drainage Class............................................................................................22
References............................................................................................................26
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
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495394 495403 495412 495421 495430 495439 495448 495457 495466 495475 495484
495394 495403 495412 495421 495430 495439 495448 495457 495466 495475 495484
40° 34' 27'' N
105° 3' 15'' W
40° 34' 27'' N
105° 3' 12'' W
40° 34' 25'' N
105° 3' 15'' W
40° 34' 25'' N
105° 3' 12'' W
N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84
0 20 40 80 120
Feet
0 5 10 20 30
Meters
Map Scale: 1:417 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
53 Kim loam, 1 to 3 percent slopes 0.7 100.0%
Totals for Area of Interest 0.7 100.0%
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
53—Kim loam, 1 to 3 percent slopes
Map Unit Setting
National map unit symbol: jpwx
Elevation: 4,800 to 5,600 feet
Mean annual precipitation: 13 to 15 inches
Mean annual air temperature: 48 to 50 degrees F
Frost-free period: 135 to 150 days
Farmland classification: Prime farmland if irrigated
Map Unit Composition
Kim and similar soils: 90 percent
Minor components: 10 percent
Estimates are based on observations, descriptions, and transects of the mapunit.
Description of Kim
Setting
Landform: Fans
Landform position (three-dimensional): Base slope
Down-slope shape: Linear
Across-slope shape: Linear
Parent material: Mixed alluvium
Typical profile
H1 - 0 to 7 inches: loam
H2 - 7 to 60 inches: loam, clay loam, sandy clay loam
H2 - 7 to 60 inches:
H2 - 7 to 60 inches:
Properties and qualities
Slope: 1 to 3 percent
Depth to restrictive feature: More than 80 inches
Natural drainage class: Well drained
Runoff class: Low
Capacity of the most limiting layer to transmit water (Ksat): Moderately high to
high (0.60 to 2.00 in/hr)
Depth to water table: More than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum in profile: 15 percent
Salinity, maximum in profile: Nonsaline to slightly saline (0.0 to 4.0 mmhos/cm)
Available water storage in profile: Very high (about 26.5 inches)
Interpretive groups
Land capability classification (irrigated): 2e
Land capability classification (nonirrigated): 4e
Hydrologic Soil Group: B
Ecological site: Loamy Plains (R067XY002CO)
Hydric soil rating: No
Custom Soil Resource Report
13
Minor Components
Fort collins
Percent of map unit: 6 percent
Hydric soil rating: No
Stoneham
Percent of map unit: 3 percent
Hydric soil rating: No
Aquic haplustolls
Percent of map unit: 1 percent
Landform: Swales
Hydric soil rating: Yes
Custom Soil Resource Report
14
Soil Information for All Uses
Soil Properties and Qualities
The Soil Properties and Qualities section includes various soil properties and
qualities displayed as thematic maps with a summary table for the soil map units in
the selected area of interest. A single value or rating for each map unit is generated
by aggregating the interpretive ratings of individual map unit components. This
aggregation process is defined for each property or quality.
Soil Erosion Factors
Soil Erosion Factors are soil properties and interpretations used in evaluating the
soil for potential erosion. Example soil erosion factors can include K factor for the
whole soil or on a rock free basis, T factor, wind erodibility group and wind erodibility
index.
Wind Erodibility Group
A wind erodibility group (WEG) consists of soils that have similar properties
affecting their susceptibility to wind erosion in cultivated areas. The soils assigned
to group 1 are the most susceptible to wind erosion, and those assigned to group 8
are the least susceptible.
15
16
Custom Soil Resource Report
Map—Wind Erodibility Group
4491437 4491446 4491455 4491464 4491473 4491482 4491491
4491437 4491446 4491455 4491464 4491473 4491482 4491491
495394 495403 495412 495421 495430 495439 495448 495457 495466 495475 495484
495394 495403 495412 495421 495430 495439 495448 495457 495466 495475 495484
40° 34' 27'' N
105° 3' 15'' W
40° 34' 27'' N
105° 3' 12'' W
40° 34' 25'' N
105° 3' 15'' W
40° 34' 25'' N
105° 3' 12'' W
N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84
0 20 40 80 120
Feet
0 5 10 20 30
Meters
Map Scale: 1:417 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 Rating Polygons
1
2
3
4
4L
5
6
7
8
Not rated or not available
Soil Rating Lines
1
2
3
4
4L
5
6
7
8
Not rated or not available
Soil Rating Points
1
2
3
4
4L
5
6
7
8
Not rated or not available
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:24,000.
Warning: Soil Map may not be valid at this scale.
Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil
line placement. The maps do not show the small areas of
contrasting soils that could have been shown at a more detailed
scale.
Please rely on the bar scale on each map sheet for map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Table—Wind Erodibility Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
53 Kim loam, 1 to 3 percent
slopes
4L 0.7 100.0%
Totals for Area of Interest 0.7 100.0%
Rating Options—Wind Erodibility Group
Aggregation Method: Dominant Condition
Component Percent Cutoff: None Specified
Tie-break Rule: Lower
Soil Qualities and Features
Soil qualities are behavior and performance attributes that are not directly
measured, but are inferred from observations of dynamic conditions and from soil
properties. Example soil qualities include natural drainage, and frost action. Soil
features are attributes that are not directly part of the soil. Example soil features
include slope and depth to restrictive layer. These features can greatly impact the
use and management of the soil.
Hydrologic Soil Group
Hydrologic soil groups are based on estimates of runoff potential. Soils are
assigned to one of four groups according to the rate of water infiltration when the
soils are not protected by vegetation, are thoroughly wet, and receive precipitation
from long-duration storms.
The soils in the United States are assigned to four groups (A, B, C, and D) and
three dual classes (A/D, B/D, and C/D). The groups are defined as follows:
Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly
wet. These consist mainly of deep, well drained to excessively drained sands or
gravelly sands. These soils have a high rate of water transmission.
Group B. Soils having a moderate infiltration rate when thoroughly wet. These
consist chiefly of moderately deep or deep, moderately well drained or well drained
soils that have moderately fine texture to moderately coarse texture. These soils
have a moderate rate of water transmission.
Group C. Soils having a slow infiltration rate when thoroughly wet. These consist
chiefly of soils having a layer that impedes the downward movement of water or
Custom Soil Resource Report
18
soils of moderately fine texture or fine texture. These soils have a slow rate of water
transmission.
Group D. Soils having a very slow infiltration rate (high runoff potential) when
thoroughly wet. These consist chiefly of clays that have a high shrink-swell
potential, soils that have a high water table, soils that have a claypan or clay layer at
or near the surface, and soils that are shallow over nearly impervious material.
These soils have a very slow rate of water transmission.
If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is
for drained areas and the second is for undrained areas. Only the soils that in their
natural condition are in group D are assigned to dual classes.
Custom Soil Resource Report
19
20
Custom Soil Resource Report
Map—Hydrologic Soil Group
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495394 495403 495412 495421 495430 495439 495448 495457 495466 495475 495484
495394 495403 495412 495421 495430 495439 495448 495457 495466 495475 495484
40° 34' 27'' N
105° 3' 15'' W
40° 34' 27'' N
105° 3' 12'' W
40° 34' 25'' N
105° 3' 15'' W
40° 34' 25'' N
105° 3' 12'' W
N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84
0 20 40 80 120
Feet
0 5 10 20 30
Meters
Map Scale: 1:417 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 Rating Polygons
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Soil Rating Lines
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Soil Rating Points
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:24,000.
Warning: Soil Map may not be valid at this scale.
Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil
line placement. The maps do not show the small areas of
contrasting soils that could have been shown at a more detailed
scale.
Please rely on the bar scale on each map sheet for map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator
projection, which preserves direction and shape but distorts
distance and area. A projection that preserves area, such as the
Albers equal-area conic projection, should be used if more
accurate calculations of distance or area are required.
This product is generated from the USDA-NRCS certified data as
Table—Hydrologic Soil Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
53 Kim loam, 1 to 3 percent
slopes
B 0.7 100.0%
Totals for Area of Interest 0.7 100.0%
Rating Options—Hydrologic Soil Group
Aggregation Method: Dominant Condition
Component Percent Cutoff: None Specified
Tie-break Rule: Higher
Drainage Class
"Drainage class (natural)" refers to the frequency and duration of wet periods under
conditions similar to those under which the soil formed. Alterations of the water
regime by human activities, either through drainage or irrigation, are not a
consideration unless they have significantly changed the morphology of the soil.
Seven classes of natural soil drainage are recognized-excessively drained,
somewhat excessively drained, well drained, moderately well drained, somewhat
poorly drained, poorly drained, and very poorly drained. These classes are defined
in the "Soil Survey Manual."
Custom Soil Resource Report
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23
Custom Soil Resource Report
Map—Drainage Class
4491437 4491446 4491455 4491464 4491473 4491482 4491491
4491437 4491446 4491455 4491464 4491473 4491482 4491491
495394 495403 495412 495421 495430 495439 495448 495457 495466 495475 495484
495394 495403 495412 495421 495430 495439 495448 495457 495466 495475 495484
40° 34' 27'' N
105° 3' 15'' W
40° 34' 27'' N
105° 3' 12'' W
40° 34' 25'' N
105° 3' 15'' W
40° 34' 25'' N
105° 3' 12'' W
N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84
0 20 40 80 120
Feet
0 5 10 20 30
Meters
Map Scale: 1:417 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 Rating Polygons
Excessively drained
Somewhat excessively
drained
Well drained
Moderately well drained
Somewhat poorly drained
Poorly drained
Very poorly drained
Subaqueous
Not rated or not available
Soil Rating Lines
Excessively drained
Somewhat excessively
drained
Well drained
Moderately well drained
Somewhat poorly drained
Poorly drained
Very poorly drained
Subaqueous
Not rated or not available
Soil Rating Points
Excessively drained
Somewhat excessively
drained
Well drained
Moderately well drained
Somewhat poorly drained
Poorly drained
Very poorly drained
Subaqueous
Not rated or not available
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:24,000.
Warning: Soil Map may not be valid at this scale.
Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil
line placement. The maps do not show the small areas of
contrasting soils that could have been shown at a more detailed
scale.
Please rely on the bar scale on each map sheet for map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Table—Drainage Class
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
53 Kim loam, 1 to 3 percent
slopes
Well drained 0.7 100.0%
Totals for Area of Interest 0.7 100.0%
Rating Options—Drainage Class
Aggregation Method: Dominant Condition
Component Percent Cutoff: None Specified
Tie-break Rule: Higher
Custom Soil Resource Report
25
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
26
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
27
. 0 1,250 2,500 5,000
Feet
SPRING CREEK BASIN
MANAGEMENT
PROPOSED CONDITION BMP MAP
Overland Trail
College Ave College Ave
Harmony Rd
Horsetooth Rd
Prospect Rd
Prospect Rd
Sheilds St
Taft Hill Rd Taft Hill Rd
Sheilds St
Drake Rd
Lemay Ave
Timberline Rd
Colorado State
University
Lemay Ave
Parkwood Lake
!(
!(
!(
!(
!(
!(
!(
Union Pacific RR
Burlington Northern RR
Burlington Northern
RR
Warren Lake
Horsetooth Reservoir
College Lake
Lake
Sherwood
Spring Canyon Park Pond (Optional)
• Retrofit Existing Pond To Accomodate
Water Quality Volume
Kensington Pond
• Retrofit Existing Pond To Accomodate
Water Quality Volume
Proposed CSU Ropes Pond
• Construct Pond To Accomodate
Water Quality Volume
Proposed Edora Pond
• Construct Pond To Accomodate
Water Quality Volume
CSU Vet Hospital Pond
• Retrofit Existing Pond To Accomodate
Water Quality Volume
Woodwest Detention Pond
• Construct Proprietary Mechanical
BMP At Pond Outlet.
Wagon Wheel Pond (Optional)
• Retrofit Existing Pond To Accomodate
Water Quality Volume
Rossborough Park Pond
• Install Water Quality Outlet To Accomodate
Circle C - Adult Residential Treatment Services Preliminary Drainage Report July 2019
B
Appendix B: BMP Sizing
and Hydrology Calculations
CIRCLE C ‐ ADULT RESIDENTIAL TREATMENT SERVICES
TABLE B‐1: BASIN PARAMETERS
Existing Condition
0.95 0.95 0.80 0.50 0.50 0.10 0.15 0.20 0.20 0.25 0.35 (acres)
A 00000 23,65700000 0.54
B1,9610000000000 0.05
TOTAL (acres) 0.05 0.00 0.00 0.00 0.00 0.54 0.00 0.00 0.00 0.00 0.00 0.59
Proposed Condition
0.95 0.95 0.80 0.50 0.50 0.10 0.15 0.20 0.20 0.25 0.35 (acres)
A1,00600000 4,339000 0.12
B8,404 7,23900000 2,201000 0.41
C1,750000000681000 0.06
TOTAL (acres) 0.26 0.17 0.00 0.00 0.00 0.00 0.00 0.17 0.00 0.00 0.00 0.59
Off‐site Basins
0.95 0.95 0.80 0.50 0.50 0.10 0.15 0.20 0.20 0.25 0.35 (acres)
OS1 0 6,8700000 10,6880000 0.40
OS21,5890000000000 0.04
TOTAL (acres) 0.04 0.16 0.00 0.00 0.00 0.00 0.25 0.00 0.00 0.00 0.00 0.44
Basin Area
Asphalt,
Concrete Rooftop
Recycled
Asphalt Gravel Pavers
Lawns, Sandy,
Slope <2%
Lawns, Clayey,
Slope >7%
Lawns, Sandy,
Slope >7%
Lawns, Clayey,
Slope <2%
Lawns, Clayey,
Slope 2‐7%
Basin Categories and Areas (SF)
Hardscape or Hard Surface Landscape or Pervious Surface
Basin I.D. Basin Area
Lawns, Sandy,
Slope 2‐7%
Basin I.D.
Basin Categories and Areas (SF)
Asphalt,
Concrete Rooftop
Recycled
Asphalt Gravel Pavers
Lawns, Sandy,
Slope <2%
Lawns, Sandy,
Slope 2‐7%
Lawns, Sandy,
Slope >7%
Lawns, Clayey,
Slope <2%
Lawns, Clayey,
Slope 2‐7%
Lawns, Clayey,
Slope >7%
Hardscape or Hard Surface Landscape or Pervious Surface
Basin I.D.
Basin Categories and Areas (SF)
Hardscape or Hard Surface Landscape or Pervious Surface Basin Area
CIRCLE C ‐ ADULT RESIDENTIAL TREATMENT SERVICES
TABLE B‐2 ‐ TIME OF CONCENTRATION
Existing Condition
100 yr
Velocity tt tc tc Check
(acres) (feet) (%) (min) (min) feet (ft/ft) (feet) (feet/sec) (min) (min) (min) (min)
A 0.10 0.13 0.54 100 1.68 15.7 15.3 338 0.008 0.100 Asphalt w/ concrete gutter 1.8 3.1 18.5 11.9 NO 11.9
B 0.95 1.00 0.05 52 5.52 1.1 0.8 0 0.000 0.000 0.0 0.0 5.0 YES 5.0
Proposed Condition
100 yr
Velocity tt tt tc Check
(acres) (feet) (%) (min) (min) feet (ft/ft) (feet) (feet/sec) (min) (min) (min) (min)
A 0.34 0.43 0.12 33 3.90 5.2 4.6 399 0.008 0.090 Asphalt w/ concrete gutter 1.7 4.0 8.6 12.2 YES 8.6
B 0.86 1.00 0.41 52 2.00 2.6 1.1 81 0.005 0.130 Asphalt w/ concrete gutter 1.7 0.8 5.0 10.5 YES 5.0
C 0.74 0.92 0.06 38 11.20 1.9 0.9 27 0.008 0.100 Asphalt w/ concrete gutter 1.8 0.3 5.0 10.2 YES 5.0
Off‐site Basins
100 yr
Velocity tt tt tc Check
(acres) (feet) (%) (min) (min) feet (ft/ft) (feet) (feet/sec) (min) (min) (min) (min)
OS1 0.46 0.58 0.40 25 25.00 2.0 1.7 125 0.010 0.010 grass swale 0.2 10.5 12.2 10.7 NO 10.7
OS2 0.95 1.00 0.04 57 6.14 1.2 0.8 27 0.008 0.090 Asphalt w/ concrete gutter 1.7 0.3 5.0 10.2 YES 5.0
Basin I.D.
Runoff Coefficient Basin Parameters
C2 C100
Area
Overland Flow tc Check
Length Hydraulic Final tc
Length Radius
Concentrated Flow
Type of Land Surface
Basin I.D.
Runoff Coefficient Basin Parameters
C2, C5 C100
Area
tc Check
100 yr ‐ ti Slope Hydraulic Final tc
Length Slope Radius
2yr ‐ ti Length
Basin I.D.
Runoff Coefficient Basin Parameters
C2
Final tc
tc Check
C100
Area
Overland Flow
Length Slope 2yr ‐ ti 100 yr ‐ ti Length
Slope 2yr ‐ ti 100 yr ‐ ti Slope
Overland Flow Concentrated Flow
Hydraulic
Slope Radius
Concentrated Flow
Type of Land Surface
Type of Land Surface
CIRCLE C ‐ ADULT RESIDENTIAL TREATMENT SERVICES
TABLE B‐3: BASIN HYDROLOGY
Existing Condition
Design Point 100‐Year 2‐Year 100‐Year
I100 Q2 Q100
(acres) (minutes) (in./hour) (in./hour) (ft3/s) (ft3/s)
A 1 0.54 11.9 0.10 0.13 2.1 7.4 0.12 0.50
B 2 0.05 5.0 0.95 1.00 2.9 10.0 0.12 0.45
Proposed Condition
100‐Year 2‐Year 100‐Year
I100 Q2 Q100
(acres) (minutes) (in./hour) (in./hour) (ft3/s) (ft3/s)
A 0.12 8.6 0.34 0.43 2.4 8.4 0.10 0.44
B 0.41 5.0 0.86 1.00 2.9 10.0 1.00 4.08
C 0.06 5.0 0.74 0.92 2.9 10.0 0.12 0.51
Off‐site Basins
100‐Year 2‐Year 100‐Year
I100 Q2 Q100
(acres) (minutes) (in./hour) (in./hour) (ft3/s) (ft3/s)
OS1 0.40 10.7 0.46 0.58 2.2 7.7 0.41 1.80
OS2 0.04 5.0 0.95 1.00 2.9 10.0 0.10 0.36
Runoff
Runoff Coefficients Rainfall Intensity Runoff
Runoff Coefficients Rainfall Intensity Runoff
2‐Year
C2
100‐Year
C100
2‐Year
I2
Basin I.D. Basin Area
Time of
Concentration
2‐Year
C2
Basin Area 2‐Year
I2
100‐Year
C100
2‐Year
C2
100‐Year
C100
2‐Year
I2
Runoff Coefficients Rainfall Intensity
Basin I.D. Basin Area
Time of
Design Point Concentration
Basin I.D.
Time of
Concentration
CIRCLE C ‐ ADULT RESIDENTIAL TREATMENT SERVICES
TABLE B‐4: WQCV
Water Quality Capture Volume
(acres) (hours) (in) (ac‐ft) (cu‐ft)
B 0.41 88% 40 0.382 0.016 682
1 WQCV=a (0.91I
3‐1.19I
2+0.78I ) Equation 7‐1
2 V=(WQCV/12)A*1.2 Equation 7‐2
WQCV
Volume2
WQCV
Basin I.D. Basin Area Volume
Percent
Impervious Drain Time
WQCV1
CIRCLE C ‐ ADULT RESIDENTIAL TREATMENT SERVICES
TABLE B‐5: IDF DATA
2‐YEAR 10‐YEAR 100‐YEAR
(minutes) (inches/hour) (inches/hour) (inches/hour)
5 2.85 4.87 9.95
6 2.67 4.56 9.31
7 2.52 4.31 8.80
8 2.40 4.10 8.38
9 2.30 3.93 8.03
10 2.21 3.78 7.72
11 2.13 3.63 7.42
12 2.05 3.50 7.16
13 1.98 3.39 6.92
14 1.92 3.29 6.71
15 1.87 3.19 6.52
16 1.81 3.08 6.30
17 1.75 2.99 6.10
18 1.70 2.90 5.92
19 1.65 2.82 5.75
20 1.61 2.74 5.60
21 1.56 2.67 5.46
22 1.53 2.61 5.32
23 1.49 2.55 5.20
24 1.46 2.49 5.09
25 1.43 2.44 4.98
26 1.40 2.39 4.87
27 1.37 2.34 4.78
28 1.34 2.29 4.69
29 1.32 2.25 4.60
30 1.30 2.21 4.52
31 1.27 2.16 4.42
32 1.24 2.12 4.33
33 1.22 2.08 4.24
34 1.19 2.04 4.16
35 1.17 2.00 4.08
36 1.15 1.96 4.01
37 1.16 1.93 3.93
38 1.11 1.89 3.87
39 1.09 1.86 3.80
40 1.07 1.83 3.74
41 1.05 1.80 3.68
42 1.04 1.77 3.62
43 1.02 1.74 3.56
44 1.01 1.72 3.51
45 0.99 1.69 3.46
46 0.98 1.67 3.41
47 0.96 1.64 3.36
48 0.95 1.62 3.31
49 0.94 1.60 3.27
50 0.92 1.58 3.23
51 0.91 1.56 3.18
52 0.90 1.54 3.14
53 0.89 1.52 3.10
54 0.88 1.50 3.07
55 0.87 1.48 3.03
56 0.86 1.47 2.99
57 0.85 1.45 2.96
58 0.84 1.43 2.92
59 0.83 1.42 2.89
60 0.82 1.40 2.86
CIRCLE C ‐ ADULT RESIDENTIAL TREATMENT SERVICES
TABLE B‐6: DETENTION VOLUME
DETENTION VOLUME BY THE MODIFIED FAA METHOD (FORT COLLINS)
Project:
Design Point:
0.41 Acres
1.00
0.12 CFS
5 Minutes
5 9.95 1222.77 34.70 1188
6 9.31 1372.94 41.64 1331
7 8.80 1514.02 48.58 1465
8 8.38 1647.73 55.53 1592
9 8.03 1776.27 62.47 1714
10 7.72 1897.45 69.41 1828
11 7.42 2006.08 76.35 1930
12 7.16 2111.77 83.29 2028
13 6.92 2211.06 90.23 2121
14 6.71 2308.89 97.17 2212
15 6.52 2403.76 104.11 2300
16 6.30 2477.49 111.05 2366
17 6.10 2548.77 117.99 2431
18 5.92 2619.06 124.93 2494
19 5.75 2685.18 131.87 2553
20 5.60 2752.77 138.81 2614
21 5.46 2818.15 145.75 2672
22 5.32 2876.64 152.70 2724
23 5.20 2939.57 159.64 2780
24 5.09 3002.49 166.58 2836
25 4.98 3060.00 173.52 2886
26 4.87 3112.11 180.46 2932
27 4.78 3172.08 187.40 2985
28 4.69 3227.62 194.34 3033
29 4.60 3278.75 201.28 3077
30 4.52 3332.82 208.22 3125
31 4.42 3367.72 215.16 3153
32 4.33 3405.57 222.10 3183
33 4.24 3439.00 229.04 3210
34 4.16 3476.36 235.98 3240
35 4.08 3509.78 242.92 3267
36 4.01 3548.12 249.86 3298
37 3.93 3573.93 256.81 3317
38 3.87 3614.49 263.75 3351
39 3.80 3642.50 270.69 3372
40 3.74 3676.91 277.63 3399
41 3.68 3708.37 284.57 3424
42 3.62 3736.89 291.51 3445
43 3.56 3762.45 298.45 3464
44 3.51 3795.87 305.39 3490
45 3.46 3826.84 312.33 3515
46 3.41 3855.35 319.27 3536
47 3.36 3881.41 326.21 3555
48 3.31 3905.00 333.15 3572
49 3.27 3938.18 340.09 3598
50 3.23 3969.40 347.03 3622
51 3.18 3986.11 353.98 3632
52 3.14 4013.15 360.92 3652
53 3.10 4038.22 367.86 3670
54 3.07 4074.59 374.80 3700
55 3.03 4095.97 381.74 3714
CIRCLE C ‐ ADULT RESIDENTIAL TREATMENT SERVICES
TABLE B‐7: LID REQUIREMENTS
PROJECT AREA
TOTAL NET NEW IMPERVIOUS AREA 16,438 SF
REQUIRED MINIMUM AREA TO BE TREATED BY LID
(75% OF NEW IMPERVIOUS AREA) 12,328 SF
NET NEW IMPERVIOUS AREA TREATED BY LID 15,643 SF
PERCENT OF NEW IMPERVIOUS AREA TREATED BY LID 95%
75% ON‐SITE TREATMENT BY LID
van
LID Contributory Area
StormTech Chamber System
CCGCOLORADO
CIVIL
GROUP, INC.
ENGINEERING CONSULTANTS
2204 HOFFMAN DRIVE
LOVELAND, COLORADO 80538
(970) 278-0029
CIRCLE C -
ADULT RESIDENTIAL
TREATMENT SERVICES
LOW IMPACT DEVELOPMENT
EXHIBIT
Circle C - Adult Residential Treatment Services Preliminary Drainage Report July 2019
C
Appendix C: Erosion Control Plan
and Drainage Plan
van
1
A
0.12 ac
19%
B
0.39 ac
92%
C
0.05 ac
72%
OS2
0.04 ac
100%
OS1
0.40 ac
39%
4962.000
MCHUGH STREET
EAST ELIZABETH STREET
PATTON STREET
B
0.05 ac
100%
A
0.54 ac
2%
OS1
0.40 ac
39%
OS2
0.04 ac
100%
B
0.05 ac
100%
A
0.54 ac
2%
OS1
0.40 ac
39%
MCHUGH STREET
EAST ELIZABETH STREET
PATTON STREET
OS2
0.04 ac
100%
X
#.## ac
#.##
X
#.## ac
#.##
#
DATE DESCRIPTION
REVISIONS
OF
DATE:
2204 HOFFMAN DRIVE
Circle C - Adult Residential Treatment Services Preliminary Drainage Report July 2019
D
Appendix D: SDI Data Sheet
Stormwater Facility Name:
Facility Location & Jurisdiction:
User (Input) Watershed Characteristics User Defined User Defined User Defined User Defined
Watershed Slope = 0.011 ft/ft Stage [ft] Area [ft^2] Stage [ft] Discharge [cfs]
Watershed Length-to-Width Ratio = 1.00 L:W 0.00 2,282 0.00 0.00
Watershed Area = 0.41 acres 2.33 2,282 0.01 0.01
Watershed Imperviousness = 88.0% percent 0.40 0.01
Percentage Hydrologic Soil Group A = percent 0.50 0.12
Percentage Hydrologic Soil Group B = percent 2.33 0.12
Percentage Hydrologic Soil Groups C/D = 100.0% percent
User Input: Detention Basin Characteristics
WQCV Design Drain Time = 40.00 hours
After completing and printing this worksheet to a pdf, go to:
https://maperture.digitaldataservices.com/gvh/?viewer=cswdif,
create a new stormwater facility, and
attach the pdf of this worksheet to that record.
Routed Hydrograph Results
Design Storm Return Period = WQCV 2 Year 5 Year 10 Year 25 Year 50 Year 100 Year
Two-Hour Rainfall Depth = 0.53 0.98 1.36 1.71 2.31 2.91 3.67 in
Calculated Runoff Volume = 0.013 0.029 0.042 0.054 0.076 0.098 0.126 acre-ft
OPTIONAL Override Runoff Volume = acre-ft
Inflow Hydrograph Volume = 0.013 0.029 0.042 0.054 0.075 0.097 0.125 acre-ft
Time to Drain 97% of Inflow Volume = 15 27 27 28 30 31 33 hours
Time to Drain 99% of Inflow Volume = 16 28 29 30 31 33 36 hours
Maximum Ponding Depth = 0.21 0.47 0.63 0.84 1.20 1.59 2.10 ft
Maximum Ponded Area = 0.052 0.052 0.052 0.052 0.052 0.052 0.052 acres
Maximum Volume Stored = 0.011 0.024 0.033 0.044 0.063 0.083 0.110 acre-ft
Stormwater Detention and Infiltration Design Data Sheet
Circle C - Adult Residential Treatment Services
Fort Collins, CO
Workbook Protected Worksheet Protected
state portal.xls, Design Data 7/1/2019, 3:00 PM
Doing_Clear_FoYes
CountA= 1
0123
#N/A
#N/A
0123
#N/A
#N/A
Check Data Set 1 Check Data Set 1
Stormwater Detention and Infiltration Design Data Sheet
Area
Discharge
0
0.5
1
1.5
2
2.5
3
3.5
0.1 1 10
FLOW [cfs]
TIME [hr]
100YR IN
100YR OUT
50YR IN
50YR OUT
25YR IN
25YR OUT
10YR IN
10YR OUT
5YR IN
5YR OUT
2YR IN
2YR OUT
WQCV IN
WQCV OUT
0
0.5
1
1.5
2
2.5
0.1 1 10 100
PONDING DEPTH [ft]
DRAIN TIME [hr]
100YR
50YR
25YR
10YR
5YR
2YR
WQCV
state portal.xls, Design Data 7/1/2019, 3:00 PM
COLORADO CIVIL GROUP, INC.
LOVELAND, COLORADO 80538
(970) 278-0029
CCGCOLORADO
CIVIL
GROUP, INC.
ENGINEERING CONSULTANTS
SHEET:
SCALE:
JOB NO:
CHECKED:
DESIGNED:
FILE NAME:
CALL THE UTILITY NOTIFICATION CENTER OF COLORADO
3 DAYS BEFORE YOU DIG
811 OR 1-800-922-1987
www.UNCC.org
JULY 3, 2019
0060.0002.00
CEM
17
CEM/EJJ/HAH
0" 1" BAR IS ONE INCH ON ORIGINAL DRAWING
CIRCLE C-ADULT RESIDENTIAL
TREATMENT SERVICES
1" = 20'
1" = 20'
0 20 40
scale feet
DRAINAGE PLAN
10
LEGEND
EXISTING CONDITION
OFF-SITE BASIN INSET PROPOSED CONDITION
1" = 50'
0 50 100
scale feet
0060.0002.00_DRAINAGE
EXISTING BASINS
PROPOSED BASINS
OFF-SITE BASINS
56 2.99 4115.39 388.68 3727
57 2.96 4146.85 395.62 3751
58 2.92 4162.58 402.56 3760
59 2.89 4190.85 409.50 3781
60 2.86 4217.64 416.44 3801
65 2.71 4329.47 451.14 3878
70 2.59 4456.05 485.85 3970
75 2.48 4571.56 520.55 4051
80 2.38 4679.71 555.26 4124
85 2.29 4784.17 589.96 4194
90 2.21 4888.63 624.66 4264
95 2.13 4973.42 659.37 4314
100 2.06 5063.13 694.07 4369
105 2.00 5161.44 728.77 4433
110 1.94 5245.01 763.48 4482
115 1.88 5313.83 798.18 4516
120 1.84 5426.89 832.88 4594
CIRCLE C ‐ RESIDENTIAL TREAMENT SERVICES
BASIN B
Design Information (Input)
Rainfall Intensity
I (inches/hour)
Outflow Volume
Vo (Cubic Feet)
Required
Detention
Volume
Vs (Cubic Feet)
Catchment Area:
Runoff Coefficent:
Allowable Maximum Release Rate:
Time of Concentration:
Storm Duration
T (minutes)
Inflow Volume
Vi (Cubic Feet)
65 0.78 1.32 2.71
70 0.73 1.25 2.59
75 0.70 1.19 2.48
80 0.66 1.14 2.38
85 0.64 1.09 2.29
90 0.61 1.05 2.21
95 0.58 1.01 2.13
100 0.56 0.97 2.06
105 0.54 0.94 2.00
110 0.52 0.91 1.94
115 0.51 0.88 1.88
120 0.49 0.86 1.84
s Stormwater Criteria Manual ‐ Table 3.4‐1
STORM RAINFALL INTENSITY
DURATION
Asphalt,
Concrete Rooftop
Recycled
Asphalt Gravel Pavers
Lawns, Sandy,
Slope <2%
Lawns, Sandy,
Slope 2‐7%
Lawns, Sandy,
Slope >7%
Lawns, Clayey,
Slope <2%
Lawns, Clayey,
Slope 2‐7%
Lawns, Clayey,
Slope >7%
Water Quality Volume
Proposed Taft and Horsetooth Pond
• Construct Pond To Accomodate
Water Quality Volume
Proposed Centre Ave Pond
• Construct Pond To Accomodate
Water Quality Volume
!(
!(
## ##
!(
##
##
##
##
##
##
##
Proposed Stream Restoration and
Habitat Improvements
Legend
## Proposed Water Quality Pond
Proposed BMP Basin Type
Flood Control Only
Water Quality Only
WQ Not Evaluated Water Drains
Into Irrigation System
Undeveloped Area
Flood Control and Water Quality
!( Proprietary Mechanical BMP
Proposed Improvement
Spring Creek Basin
Proposed Stream Restoration
and Habitat Improvements
Maps from the Web Soil Survey are based on the Web Mercator
projection, which preserves direction and shape but distorts
distance and area. A projection that preserves area, such as the
Albers equal-area conic projection, should be used if more
accurate calculations of distance or area are required.
This product is generated from the USDA-NRCS certified data as
of the version date(s) listed below.
Soil Survey Area: Larimer County Area, Colorado
Survey Area Data: Version 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: Aug 11, 2018—Aug
12, 2018
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor
shifting of map unit boundaries may be evident.
Custom Soil Resource Report
24
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: Aug 11, 2018—Aug
12, 2018
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor
shifting of map unit boundaries may be evident.
Custom Soil Resource Report
21
Maps from the Web Soil Survey are based on the Web Mercator
projection, which preserves direction and shape but distorts
distance and area. A projection that preserves area, such as the
Albers equal-area conic projection, should be used if more
accurate calculations of distance or area are required.
This product is generated from the USDA-NRCS certified data as
of the version date(s) listed below.
Soil Survey Area: Larimer County Area, Colorado
Survey Area Data: Version 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: Aug 11, 2018—Aug
12, 2018
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor
shifting of map unit boundaries may be evident.
Custom Soil Resource Report
17
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: Aug 11, 2018—Aug
12, 2018
The orthophoto or other base map on which the soil lines were
compiled and digitized probably differs from the background
imagery displayed on these maps. As a result, some minor
shifting of map unit boundaries may be evident.
Custom Soil Resource Report
10