Press Alt + R to read the document text or Alt + P to download or print.
This document contains no pages.
HomeMy WebLinkAboutDrainage Reports - 05/05/2022Fairway Lane Apartments – Fort Collins, CO
Final Drainage Report
Project No. 20065
Jensen LaPlante Development
1603 Oakridge Drive, Suite #101
Fort Collins, CO 80525
Submittal Date: 1/18/2022
Wes Lamarque
5/5/2022
March 30, 2022
City of Fort Collins
Stormwater Utility
700 Wood Street
Fort Collins, Colorado 80521
RE: Final Drainage and Erosion Control Report for
FAIRWAY LANE APARTMENTS
Dear Staff:
Sanderson Stewart is pleased to submit this Final Drainage and Erosion Control Report for your review.
This report accompanies the Final Development Plan submittal for the proposed Fairway Lane
Apartments.
This report has been prepared in accordance to Fort Collins Stormwater Criteria Manual (FCSCM) and
serves to document the stormwater impacts associated with the proposed project. We understand that
review by the City is to assure general compliance with standardized criteria contained in the FCSCM.
If you should have any questions as you review this report, please feel free to contact us.
Sincerely,
SANDERSON STEWART
Charles Sonnier, PE
Senior Engineer/Project Manager
Fairway Lane Apartments March 30, 2022 Page 1
Project No. 20065
March 30, 2022
Project No. 20065
FINAL (FDP) STORMWATER MANAGEMENT REPORT
FOR
FAIRWAY LANE APARTMENTS
FORT COLLINS, COLORADO
I. Overview Narrative
The proposed project is a multi-family development that will include the construction of eight new
apartment buildings, eight garages, a clubhouse with amenities and supporting infrastructure
improvements. The purpose of this report is to identify the required stormwater management and water
quality facilities for the developed site. The design standards governing this project are the Fort Collins
Stormwater Criteria Manual (FCSCM), Dec 2018 and the Mile High Flood District’s Urban Storm
Drainage Criteria Manual (USDCM), Volume 1-3.
II. General Project Location
The proposed development is approximately 11 acres located at the northwest corner of the South
College Avenue and West Fairway Lane intersection. The project site associated with this report
encompasses existing Parcel Nos. 9602100006, 9602100012, 9602100015, and 9602109002. More
specifically, the project site lies within the northeast corner of Section 3, Township 6 North, Range 69
West, latitude 40.5188, longitude -104.5.0785. The site is generally bounded by the Fort Collins South
Transit Center/Fossil Boulevard on the west, the Spradley Barr Ford car dealership on the north,
College Avenue on the east and Fairway Lane on the south. Surrounding properties include: the Spradley
Barr Ford car dealership adjacent to the property on the north side, Woodley’s Fine Furniture,
Worldpac, and Florida Tile on the south side of Fairway Lane Road, and VCA Fort Collins Animal
Hospital, and Fossil Ridge Animal Hospital east of South College Avenue. The existing project site is
undeveloped and has several mature trees with the ground cover consisting of small shrubs and grasses.
Refer to Appendix A for a Vicinity map.
III. Existing Site Information
Major Basin Description
This property is located within the City of Fort Collins Fossil Creek Drainage Basin that outfalls to the
Poudre River drainage basin which is a major tributary to the South Platte River.
Sub-Basin Description
The site is mostly flat to minimally sloped. Generally, runoff from the site sheet flows to the east and
south to the existing detention pond, travels through an existing 15” RCP pipe to a water quality facility
on the Woodley’s property south of Fairway Lane. The flow is then conveyed through a curb chase onto
College Avenue where it is picked up by curb inlets approximately 700 feet south and 1400 feet south of
the Woodley’s property, and ultimately discharges into Fossil Creek. Flow then conveys southeast
approximately 2.5 miles to the Fossil Creek Reservoir and then another 0.5 miles from the Fossil Creek
Reservoir Outlet to the Cache La Poudre River.
Fairway Lane Apartments March 30, 2022 Page 2
Project No. 20065
This project site sits within the FEMA Zone X, Area of Minimal flood Hazard, per FEMA FIRM Maps
08069C1000F, dated December 19, 2006.
According to the NRCS website, the site consists of primarily Nunn clay loam, 1 to 3 percent slopes,
and Fort Collins loam, 0 to 3 percent slopes, both classified as Type C soils. The soils have an erodibility
factor of 0.28 to 0.43 which suggests a moderate susceptibility to sheet and rill erosion by runoff.
Refer to Appendix A for soil data and floodplain map.
IV. Project Description
The proposed project will consist of eight new multi-family buildings, eight garages, and one clubhouse.
Proposed utility improvements will consist of storm sewer, sanitary sewer, and waterline improvements.
Surface improvements will include driveway, parking lot, landscaped areas and concrete sidewalk
surrounding the buildings. Off-site improvements will mainly consist of adjacent sidewalks, a driveway
connection, and an emergency access connection on the north side of the site connecting to the adjacent
property. Refer to Appendix A for Site Plan.
V. Drainage Design Criteria
A. Regulations/Development Criteria
The design standards governing this project are the Fort Collins Stormwater Criteria Manual
(FCSCM), Dec 2018 and the Mile High Flood District’s Urban Storm Drainage Criteria Manual
(USDCM), Volume 1-3.
B. Four-Step Process
The overall stormwater management strategy to be employed with the proposed project will
utilize the “Four Step Process” to minimize adverse impacts of urbanization on receiving
waters. The following is a description of how the proposed development will incorporated
each step.
Step 1 – Employ Runoff Reduction Practices
Several techniques will be utilized with the proposed development to facilitate the reduction of
runoff peaks, volumes, and pollutant loads by implementing multiple Low Impact
Development (LID) strategies. Proposed techniques will include providing landscaped islands
and buffer areas throughout the site to reduce the overall impervious area, to minimize directly
connected impervious areas (MDCIA) and to grade the site such that runoff is routed over a
longer distance to increase the time of concentration.
Step 2 – Implement BMPs That Provide a Water Quality Capture Volume (WQCV) with Slow
Release
The efforts taken in Step 1 will facilitate the reduction of runoff; however, urban
development of this intensity will still generate stormwater runoff that will require additional
BMPs and water quality. The majority of stormwater runoff from the site will ultimately be
treated by the proposed detention pond with an associated outlet structure on the southeast
corner of the property. The detention pond will act as a sedimentation basin by allowing for
the sediment, fines and pollution suspended in the stormwater to settle out before being
released downstream.
Fairway Lane Apartments March 30, 2022 Page 3
Project No. 20065
Step 3 – Stabilize Streams
There are no major wet drainage conveyances within the subject property.
Step 4 – Implement Site Specific and Other Source Control BMPs
The proposed project will improve upon site specific source controls compared to historic
conditions: The proposed development will provide water quality treatment measures; thus,
eliminating sources of potential pollution previously left exposed to weathering and runoff
processes. The site-specific measure for this project that will provide a higher level of water
quality treatment (LID) will consist of (2) sub-surface StormTech systems, one located north
central of the site divided into an east and west system, and one located to the south of the site.
C. Hydrological Criteria
1. The City of Fort Collins Rainfall Intensity-Duration-Frequency Curves, as depicted
in Figure 3.4-1 of the FCSCM, serve as the source for all hydrologic computations
associated with the proposed development. Tabulated data contained in Table 3.4-1
in the FCSCM has been utilized for Rational Method runoff calculations. Refer to
Appendix B for criteria used.
2. The Rational Method will be utilized to compute stormwater runoff utilizing
coefficients and calculation methods contained in Chapter 5, Section 3.2 of the
FCSCM.
3. Three separate design storms will be utilized to address distinct drainage scenarios.
The first design storm event analyzed was the “Minor,” or “Initial” Storm, which
has a 2-year recurrence interval. The second event considered is the “Major Storm,”
which has a 100-year recurrence interval. The third storm computed, for
comparison purposes only, was the 10-year event.
4. The project site falls within the Fossil Creek Drainage Basin. According to the City
of Fort Collins, the developed release rate from the stie must be a maximum 0.2
cfs/acre.
5. No other assumptions or calculation methods have been used with this
development that are not referenced by current City of Fort Collins criteria.
6. Per recent meetings with City Stormwater staff, it was discussed that the preferred
outfall would be to utilize the existing Weberg PUD outfall pipe that discharges to
the south across the Woodly’s parking lot that ultimately collects in a water quality
pond near the southeast corner of the parking lot and discharges to the South
College Avenue right-of-way. Most, if not all, of the existing outfall pipe across the
Woodly’s parking lot lies within an existing access and drainage easement.
Coordination with Woodly’s Furniture store ownership and Water Utilities
Development Review has been completed regarding discharging to this pipe and
agreements put in place for maintenance of the storm pipe. Refer to Appendix F for
excerpt of Weberg PUD Drainage Report and Plat.
Fairway Lane Apartments March 30, 2022 Page 4
Project No. 20065
D. Hydraulic Criteria
1. All drainage and LID facilities proposed with the project are designed in accordance
with criteria outlined in the FCSCM and/or the USDCM. Refer to Appendix B for
Rational Method calculation.
E. Modifications of Criteria
1. The proposed development is not requesting any modifications to criteria at this
time.
VI. Proposed Drainage Facilities
A. General Concept
The intent of the proposed design is to safely and adequately convey the minor and major
design storm given the site’s existing constraints that were previously mentioned.
1. Stormwater from the project site will be collected into a proposed pond at the
southeast corner of the site. This will serve as detention and provide standard water
quality treatment for the contributing basins totaling approximately 10.8-acres.
2. A more detailed description of the projects sub-basins and drainage patterns is
provided below.
B. Specific Details
The proposed storm drainage system will collect runoff via sheet flow, curb and gutter and
drainage pans and convey to proposed area and curb inlets. The storm drain piping will then
convey the collected stormwater to the proposed detention pond on the southeast corner of the
property. Three total outfall pipes are proposed to discharge into the proposed detention pond.
The basins contributory to the proposed detention pond and the off-site basins are described
below.
1. There are nineteen (19) total sub-basins analyzed for this project. Seventeen (17)
basins will be collected in the proposed storm system and detention pond while the
two (2) remaining basins consist of areas that cannot be captured and detained but
instead will flow to South College Avenue. These basins are further described below.
Sub-Basin Nos. 1 through 4 and Nos. 6 through 17: These sub-basins total to
approximately 10.8 acres and are proposed to be collected in various storm inlets
throughout the site via sheet flow, curb and gutter and drainage pans. The flow will
then be piped to two (2) outfalls into the proposed detention pond. These basins
generally are comprised of rooftop, driveway and parking lot, sidewalk, and
landscaping. The percent composite imperviousness for these basins is approximately
61%.
Sub-Basin 5: This sub-basin totals to approximately 0.82 acres and consists of the
southeast side of the transit center, the east half of Fossil Blvd, and the north side of
Fairway Lane. The runoff is proposed to be collected in a storm inlet just to the east of
the proposed access off West Fairway Lane. The flow will then be piped directly into
the proposed detention pond at design point 5. The percent composite imperviousness
of this basin is approximately 53%.
Fairway Lane Apartments March 30, 2022 Page 5
Project No. 20065
Sub-Basin OS-1: This basin consists of a 0.27-acre area that cannot be collected or
conveyed to the proposed detention pond. OS-1 is located along the east side of the
site and will generally sheet flow east to the South College Avenue right-of-way. The
percent composite imperviousness of this basin is approximately 67% with an
approximate discharge rate of 0.54 cfs (2-year) and 2.3 cfs (100-year). To help off-set
the flow that cannot be captured from this basin, approximately 0.41 acres of Basin 5 is
proposed to be captured from off-site and conveyed to the proposed on-site detention
basin (a net-positive 0.14-acre capture).
Sub-Basin OS-2: Basin OS-2 is a small 0.12-acre strip of the north half of Fossil Blvd
that currently flows into the existing detention basin for Lot 2 of the Weberg PUD.
The on-site grading of the proposed detention pond would prevent this basin from
being directed into the proposed detention pond and is therefore proposed to flow east
to the South College Avenue right-of-way and then south to the same point that the
flow from this basin historically discharges to. The percent composite imperviousness
of this basin is approximately 92% with an approximate discharge rate of 0.30 cfs (2-
year) and 1.2 cfs (100-year).
Refer to Appendix B for the Drainage Basin Map
2. A curb cut currently exists at the southeast edge of the Spradley Barr Ford Dealership
property to accommodate a future road to the south from the Spradley Barr property.
Stormwater currently flows into the project site at this location and over a riprap
rundown. This project proposes to re-establish the curb line at this location as the
future roadway will no longer be constructed. As a result, stormwater on the Spradley
Barr property will continue to flow east to the South College Avenue right-of-way
rather than flow onto the project site.
3. Standard water quality and LID treatment will be served by the detention facility at
the southeast portion of the site and two (2) StormTech systems located north central
(divided into east and west systems) and south of the project site.
4. The MHFD spreadsheets were used to calculate the inlet capacities and perform the
detention pond outlet works design. The storm pipe capacities and HGLs were
modeled using Hydraflow Storm Sewers Extension for Autodesk Civil 3D Version:
2019.2 by Autodesk, Inc. Refer to Appendix C for inlet and storm drain calculations.
5. Stormwater facility Standard Operating Procedures (SOP) will be provided by the
City of Fort Collins in the Development Agreement, as required.
C. Low Impact Development (LID)
The LID requirement option for this project will treat at least 75% of the new and/or
modified impervious areas. Proposed on-site LID treatment intended to meet this
requirement will include two (2) sub-surface StormTech chamber systems sized to
accommodate the required WQCV for the project site. The north system (S1) is split
into east and west sub-systems that will collectively be designed to intercept
approximately 91,874 sf of new and/or modified impervious area and treat 3.007 cu-ft
of WQCV. The south system (S2) will be designed to intercept approximately 124,846
sf of new and/or modified impervious area and treat 4,264 cu-ft of WQCV.
Considering all systems on a total project site level, 75.9% of the new and or modified
Fairway Lane Apartments March 30, 2022 Page 6
Project No. 20065
impervious areas will be treated and 7,271 cu-ft of WQCV will be provided (6,993 cu-ft
is required). Refer to Appendix E for StormTech LID Location Exhibit and associated
calculations for each system.
D. Detention Pond Design
The proposed detention pond is located at the southeast corner of the site. The basin is designed to
store the required runoff from the proposed site and attenuate the flows to at or below the developed
maximum release rate for the Fossil Creek Drainage Basin of 0.2 cfs/acre. The detention basin will also
be designed to treat and release the WQCV with a 40-hour drain time.
The detention pond’s outlet structure is designed with an orifice plate to slowly discharge the water
quality volume while the structure’s horizontal and vertical openings will attenuate the flows to at or
below the maximum 0.2 cfs/acre release rate. An emergency spillway will be designed to pass the
developed 100-year event to the Fairway Lane right-of-way with the crest set at 4998.00.
The control structure will utilize the existing 15-inch RCP outfall pipe that will convey runoff south
under Fairway Lane, through the Weberg property, and outfall to the College Avenue Right-Of-Way.
The condition of the outfall pipe was evaluated through a video camera and jet cleaning. It was
determined that the pipe was in good functioning condition and sufficient for use by the proposed
development.
Refer to Table 1 below for proposed detention basin input parameters and storage volume results.
Table 1. Proposed Detention Basin Summary Table
Pond ID
Contributing
Area
(Acres)
Allowed
Release
Rate @
0.2
cfs/acre
Required
100-yr
Detention
Volume
(ac-ft)
Provided
100-yr
Detention
Volume
(ac-ft)
100-yr
Water
Surface
Elevation
(ft)
SE
Pond 10.82 2.16 2.35 2.37 4998.0
Also refer to Appendix D for supporting detention pond calculations.
Inlet and pipe sizing were calculated/modeled per City requirements and are presented in this report
(refer to Appendix C).
VII. Variance Requests (if necessary)
The proposed development is not requesting any variances at this time.
VIII. Erosion Control
Erosion and sediment control will be achieved through construction control measure to include various
BMPs selected from the FCSCM such as silt fencing, vehicle tracking devices, inlet/outlet protection
and curb protection, concrete washout, vehicle tracking control and stabilized staging areas. BMP
locations will be shown in the corresponding Utility Plans associated with this report. A separate
Erosion Control Report and Erosion Control Plans has been provided as part of the Final Development
Plan submittal.
Fairway Lane Apartments March 30, 2022 Page 7
Project No. 20065
IX. Conclusion
The proposed drainage system design will provide safe conveyance of the minor and major storm events
while providing increased water quality treatment compared to the existing condition.
The City of Fort Collins Stormwater Criteria Manual has been used to establish the criteria for the
developed condition stormwater management plan within the project area.
A. Compliance with Standards
1. The drainage design proposed with the proposed project complies with the City of Fort
Collins’ Stormwater Criteria Manual.
2. The drainage design proposed with this project complies with requirements for the
Fossil Creek Drainage Basin.
3. The drainage plan and stormwater management measures proposed with the proposed
development are compliant with all applicable State and Federal regulations governing
stormwater discharge.
4. The erosion control materials that will be submitted with the final plans will comply
with the requirements set forth by the City of Fort Collins’ Stormwater Criteria Manual
and the Urban Storm Drainage Criteria Manual.
B. Drainage Concept
1. The drainage design proposed with this project will effectively limit any potential
flooding and/or damage associated with runoff quantities while effectively treating
runoff through water quality mitigation features.
2. Standard water quality and LID treatment will be provided by such measures as grass
buffers, grassed swales, proposed detention pond, and sub-surface StormTech systems.
Fairway Lane Apartments March 30, 2022 Page 8
Project No. 20065
REFERENCES
1. City of Fort Collins, December 2018, Fort Collins Stormwater Criteria Manual.
2. Mile High Flood District, 2001 (November 2010 with some sections updated April 2018),
Urban Storm Drainage Criteria Manual, Volume 3, Stormwater Quality.
3. United States Department of Agriculture Natural Resources Conservation Service; Web Soil
Survey; accessed on-line September 2019.
4. Federal Emergency Management Agency; FEMA Flood Map Service Center; accessed on-line
September 2019.
APPENDICES
1. Appendix A - Site Information
a. Vicinity Map
b. Site Plan
c. NRCS Soils Data
d. FEMA Maps
2. Appendix B – Hydrologic Calculations
a. Storm Criteria
b. Drainage Basin Map
c. Rational Calculations
3. Appendix C – Hydraulic Calculations
a. Inlet Calculations
b. Storm Drain Modeling
4. Appendix D – Detention Basin Calculation
a. Detention Basin Volume Calculations
b. Outlet Works Calculations
c. Emergency Spillway Calculations
5. Appendix E – LID Exhibit & Calculations
a. LID Exhibit with StormTech Calculations
6. Appendix F - Relevant Drainage Reports
a. Pages from the Weberg PUD Drainage Report
APPENDIX A Fairway Lane Apartments – Fort Collins, CO
20065
ProjectSite
BLDG
7
BLDG
5
BLDG
6
BLDG
4
BLDG
3
BLDG
2
BLDG
8
BLDG
1LOT 1SOUTH TRANSIT CENTER SUBDIVISIONLOT 1
SPRADLEY BARR FORD SUBDIVISION
LOT 1
WEBERG, P.U.D.FOSSIL BLVDLOT 1
GEORGE T. SANDERS CO. P.U.D.
REC. NO. 19960013545
WEST FAIRWAY LANE SOUTH COLLEGE AVENUE (SH 287)0 50
SCALE: 1" = 50'
1002550
FINAL DEVELOPMENT PLANNORTH
FILE:PROJECT NO:CAD:QUALITY ASSURANCE:DRAWING HISTORYDATE DESCRIPTIONSITE PLANFAIRWAY APARTMENTSCOLLEGE AVE & FAIRWAY LANEFORT COLLINS, COLORADOC3.0 CJS20065_SITE_PROD.DWGERB3/30/22FINAL FDP PLANS--------------------------------------20065 PLAN NOTES
1 NEW ASPHALT PAVING
NEW CONCRETE WALK
NEW ACCESSIBILITY RAMP
NEW 4" PAINTED WHITE STRIPE AT 3' O.C. (TYP.)
NEW PAINTED INTERNATIONAL DISABLED SYMBOL (TYP.)
NEW 4" PAINTED WHITE PARKING STRIPE (TYP.)
NEW HIGH VOLUME DRIVE TYPE III CONCRETE DRIVE
APPROACH PER LCUASS STANDARDS
12" WHITE STOP BAR
STOP SIGN (R1-1)
NEW TRASH PAD AND ENCLOSURE (TYP.) (SEE ARCH. FOR DETAILS)
2
3
4
5
6
7
8
9
10
NEW BIKE RACKS11
ACCESSIBILITY NOTE
1.ACCESSIBLE ROUTE TO MEET THE MINIMUM STANDARDS
SET FORTH BY THE ADA STANDARDS FOR ACCESSIBLE
DESIGN, LATEST EDITION.
POOL AND AMENITY AREA (GRILL AREAS, FIRE TABLES, CABANAS, ETC.)12
TRANSFORMER PAD
PARK SPACE/PLAYGROUND/TOT LOT
2' SOFT PAN TRICKLE CHANNEL
OUTLET STRUCTURE & SCOURSTOP PROTECTION
13
14
15
16
SECONDARY EMERGENCY ACCESS WITH EMERGENCY ACCESS GATE AND
ROLL-OVER CURB17
2' CONCRETE TRICKLE CHANNEL18
NEW CURB AND GUTTER (TYP.)19
DOG PARK20
CAR CARE CENTER & DOG WASH21
BIKE SHELTER22
LIGHT POLES (TYP.)23
PEDESTRIAN CORRIDOR AREA (SEE ARCH PLANS)24
PEDESTRIAN HANDICAP RAMPS (TYP.)25
RAISED PEDESTRIAN CROSSING (SEE DETAILS)26
STANDARD 90 DEGREE PARKING SPACE WITH 2' OVERHANG (TYP.)27
SIDEWALK ANGLED PARKING SPACE WITH 2' OVERHANG (TYP.)28
STANDARD COMPACT PARKING SPACES (TYP.)29
PARALLEL PARKING SPACES (TYP.)30
NOTES:
1.EXISTING UNDERGROUND INSTALLATIONS & PRIVATE UTILITIES SHOWN ARE INDICATED
ACCORDING TO THE BEST INFORMATION AVAILABLE TO THE ENGINEER. THE ENGINEER DOES NOT
GUARANTEE THE ACCURACY OF SUCH INFORMATION. SERVICE LINES (WATER, POWER, GAS,
STORM, SEWER, TELEPHONE & TELEVISION) MAY NOT BE STRAIGHT LINES OR AS INDICATED ON
THE PLANS. STATE LAW REQUIRES CONTRACTOR TO CALL ALL UTILITY COMPANIES BEFORE
EXCAVATION FOR EXACT LOCATIONS.
2.UNLESS OTHERWISE SPECIFIED, ALL CONSTRUCTION LAYOUT AND STAKING SHALL BE PERFORMED
UNDER THE RESPONSIBLE CHARGE OF A LAND SURVEYOR LICENSED IN THE STATE WHERE THE
PROJECT IS LOCATED AND BY A PARTY CHIEF OR ENGINEERING TECHNICIAN EXPERIENCED IN
CONSTRUCTION LAYOUT AND STAKING TECHNIQUES AS ARE REQUIRED BY THE SPECIFIC TYPE OF
WORK BEING PERFORMED.
FIRE DEPARTMENT CONNECTION (FDC)31
STABILIZED POND ACCESS32
SECONDARY EMERGENCY ACCESS
NON-ENGINEERED GRAY ALLAN BLOCK RETAINING WALL (VARYING HEIGHT - 1 FT TO 2.5 FT)33
MAIL KIOSK34
AIR CONDITIONING CONDENSER UNITS
FIRE LANE NOTE
1.ALL FIRE LANES SHALL BE CAPABLE OF SUPPORTING 40
TONS.
POND GAUGE (SEE DETAILS)35
ELECTRIC VEHICLE PARKING SPACES (TYP)36
FUTURE ELECTRIC VEHICLE PARKING SPACES (TYP)37
SIDEWALK CHASE (TYP.), TO BE NDS 5" PRO SERIES CHANNEL DRAIN KIT,
OR ACO SERIES K100 DRAIN KIT OR APPROVED EQUAL
38
9
Custom Soil Resource Report
Soil Map
448516044852004485240448528044853204485360448540044854404485480448516044852004485240448528044853204485360448540044854404485480493240 493280 493320 493360 493400 493440 493480
493240 493280 493320 493360 493400 493440 493480
40° 31' 12'' N 105° 4' 47'' W40° 31' 12'' N105° 4' 36'' W40° 31' 1'' N
105° 4' 47'' W40° 31' 1'' N
105° 4' 36'' WN
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84
0 50 100 200 300
Feet
0 20 40 80 120
Meters
Map Scale: 1:1,650 if printed on A portrait (8.5" x 11") sheet.
Soil Map may not be valid at this scale.
MAP LEGEND MAP INFORMATION
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Soil Map Unit Polygons
Soil Map Unit Lines
Soil Map Unit Points
Special Point Features
Blowout
Borrow Pit
Clay Spot
Closed Depression
Gravel Pit
Gravelly Spot
Landfill
Lava Flow
Marsh or swamp
Mine or Quarry
Miscellaneous Water
Perennial Water
Rock Outcrop
Saline Spot
Sandy Spot
Severely Eroded Spot
Sinkhole
Slide or Slip
Sodic Spot
Spoil Area
Stony Spot
Very Stony Spot
Wet Spot
Other
Special Line Features
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Background
Aerial Photography
The soil surveys that comprise your AOI were mapped at
1:24,000.
Warning: Soil Map may not be valid at this scale.
Enlargement of maps beyond the scale of mapping can cause
misunderstanding of the detail of mapping and accuracy of soil
line placement. The maps do not show the small areas of
contrasting soils that could have been shown at a more detailed
scale.
Please rely on the bar scale on each map sheet for map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL:
Coordinate System: Web Mercator (EPSG:3857)
Maps from the Web Soil Survey are based on the Web Mercator
projection, which preserves direction and shape but distorts
distance and area. A projection that preserves area, such as the
Albers equal-area conic projection, should be used if more
accurate calculations of distance or area are required.
This product is generated from the USDA-NRCS certified data as
of the version date(s) listed below.
Soil Survey Area: Larimer County Area, Colorado
Survey Area Data: Version 15, Jun 9, 2020
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
Map Unit Legend
Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI
35 Fort Collins loam, 0 to 3 percent
slopes
3.4 26.8%
74 Nunn clay loam, 1 to 3 percent
slopes
9.4 73.2%
Totals for Area of Interest 12.9 100.0%
Map Unit Descriptions
The map units delineated on the detailed soil maps in a soil survey represent the
soils or miscellaneous areas in the survey area. The map unit descriptions, along
with the maps, can be used to determine the composition and properties of a unit.
A map unit delineation on a soil map represents an area dominated by one or more
major kinds of soil or miscellaneous areas. A map unit is identified and named
according to the taxonomic classification of the dominant soils. Within a taxonomic
class there are precisely defined limits for the properties of the soils. On the
landscape, however, the soils are natural phenomena, and they have the
characteristic variability of all natural phenomena. Thus, the range of some
observed properties may extend beyond the limits defined for a taxonomic class.
Areas of soils of a single taxonomic class rarely, if ever, can be mapped without
including areas of other taxonomic classes. Consequently, every map unit is made
up of the soils or miscellaneous areas for which it is named and some minor
components that belong to taxonomic classes other than those of the major soils.
Most minor soils have properties similar to those of the dominant soil or soils in the
map unit, and thus they do not affect use and management. These are called
noncontrasting, or similar, components. They may or may not be mentioned in a
particular map unit description. Other minor components, however, have properties
and behavioral characteristics divergent enough to affect use or to require different
management. These are called contrasting, or dissimilar, components. They
generally are in small areas and could not be mapped separately because of the
scale used. Some small areas of strongly contrasting soils or miscellaneous areas
are identified by a special symbol on the maps. If included in the database for a
given area, the contrasting minor components are identified in the map unit
descriptions along with some characteristics of each. A few areas of minor
components may not have been observed, and consequently they are not
mentioned in the descriptions, especially where the pattern was so complex that it
was impractical to make enough observations to identify all the soils and
miscellaneous areas on the landscape.
The presence of minor components in a map unit in no way diminishes the
usefulness or accuracy of the data. The objective of mapping is not to delineate
pure taxonomic classes but rather to separate the landscape into landforms or
landform segments that have similar use and management requirements. The
delineation of such segments on the map provides sufficient information for the
development of resource plans. If intensive use of small areas is planned, however,
Custom Soil Resource Report
11
onsite investigation is needed to define and locate the soils and miscellaneous
areas.
An identifying symbol precedes the map unit name in the map unit descriptions.
Each description includes general facts about the unit and gives important soil
properties and qualities.
Soils that have profiles that are almost alike make up a soil series. Except for
differences in texture of the surface layer, all the soils of a series have major
horizons that are similar in composition, thickness, and arrangement.
Soils of one series can differ in texture of the surface layer, slope, stoniness,
salinity, degree of erosion, and other characteristics that affect their use. On the
basis of such differences, a soil series is divided into soil phases. Most of the areas
shown on the detailed soil maps are phases of soil series. The name of a soil phase
commonly indicates a feature that affects use or management. For example, Alpha
silt loam, 0 to 2 percent slopes, is a phase of the Alpha series.
Some map units are made up of two or more major soils or miscellaneous areas.
These map units are complexes, associations, or undifferentiated groups.
A complex consists of two or more soils or miscellaneous areas in such an intricate
pattern or in such small areas that they cannot be shown separately on the maps.
The pattern and proportion of the soils or miscellaneous areas are somewhat similar
in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example.
An association is made up of two or more geographically associated soils or
miscellaneous areas that are shown as one unit on the maps. Because of present
or anticipated uses of the map units in the survey area, it was not considered
practical or necessary to map the soils or miscellaneous areas separately. The
pattern and relative proportion of the soils or miscellaneous areas are somewhat
similar. Alpha-Beta association, 0 to 2 percent slopes, is an example.
An undifferentiated group is made up of two or more soils or miscellaneous areas
that could be mapped individually but are mapped as one unit because similar
interpretations can be made for use and management. The pattern and proportion
of the soils or miscellaneous areas in a mapped area are not uniform. An area can
be made up of only one of the major soils or miscellaneous areas, or it can be made
up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example.
Some surveys include miscellaneous areas. Such areas have little or no soil
material and support little or no vegetation. Rock outcrop is an example.
Custom Soil Resource Report
12
Larimer County Area, Colorado
35—Fort Collins loam, 0 to 3 percent slopes
Map Unit Setting
National map unit symbol: 2tlnc
Elevation: 4,020 to 6,730 feet
Mean annual precipitation: 14 to 16 inches
Mean annual air temperature: 46 to 48 degrees F
Frost-free period: 135 to 160 days
Farmland classification: Prime farmland if irrigated
Map Unit Composition
Fort collins and similar soils:85 percent
Minor components:15 percent
Estimates are based on observations, descriptions, and transects of the mapunit.
Description of Fort Collins
Setting
Landform:Stream terraces, interfluves
Landform position (three-dimensional):Interfluve, tread
Down-slope shape:Linear
Across-slope shape:Linear
Parent material:Pleistocene or older alluvium and/or eolian deposits
Typical profile
Ap - 0 to 4 inches: loam
Bt1 - 4 to 9 inches: clay loam
Bt2 - 9 to 16 inches: clay loam
Bk1 - 16 to 29 inches: loam
Bk2 - 29 to 80 inches: loam
Properties and qualities
Slope:0 to 3 percent
Depth to restrictive feature:More than 80 inches
Drainage class:Well drained
Runoff class: Low
Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high
(0.20 to 2.00 in/hr)
Depth to water table:More than 80 inches
Frequency of flooding:None
Frequency of ponding:None
Calcium carbonate, maximum content:12 percent
Maximum salinity:Nonsaline to very slightly saline (0.1 to 2.0 mmhos/cm)
Available water capacity:High (about 9.1 inches)
Interpretive groups
Land capability classification (irrigated): 3e
Land capability classification (nonirrigated): 3e
Hydrologic Soil Group: C
Ecological site: R067BY002CO - Loamy Plains
Hydric soil rating: No
Custom Soil Resource Report
13
Minor Components
Nunn
Percent of map unit:10 percent
Landform:Stream terraces
Landform position (three-dimensional):Tread
Down-slope shape:Linear
Across-slope shape:Linear
Ecological site:R067BY002CO - Loamy Plains
Hydric soil rating: No
Vona
Percent of map unit:5 percent
Landform:Interfluves
Landform position (three-dimensional):Side slope, interfluve
Down-slope shape:Linear
Across-slope shape:Linear
Ecological site:R067BY024CO - Sandy Plains
Hydric soil rating: No
74—Nunn clay loam, 1 to 3 percent slopes
Map Unit Setting
National map unit symbol: 2tlpl
Elevation: 3,900 to 5,840 feet
Mean annual precipitation: 13 to 17 inches
Mean annual air temperature: 50 to 54 degrees F
Frost-free period: 135 to 160 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 9 inches: clay loam
Bt - 9 to 13 inches: clay loam
Btk - 13 to 25 inches: clay loam
Bk1 - 25 to 38 inches: clay loam
Bk2 - 38 to 80 inches: clay loam
Custom Soil Resource Report
14
Properties and qualities
Slope:1 to 3 percent
Depth to restrictive feature:More than 80 inches
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 content:7 percent
Maximum salinity:Nonsaline to very slightly saline (0.1 to 2.0 mmhos/cm)
Sodium adsorption ratio, maximum:0.5
Available water capacity:High (about 9.9 inches)
Interpretive groups
Land capability classification (irrigated): 2e
Land capability classification (nonirrigated): 3e
Hydrologic Soil Group: C
Ecological site: R067BY042CO - Clayey Plains
Hydric soil rating: No
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:R067BY042CO - Clayey Plains
Hydric soil rating: No
Satanta
Percent of map unit:5 percent
Landform:Terraces
Landform position (three-dimensional):Tread
Down-slope shape:Linear
Across-slope shape:Linear
Ecological site:R067BY002CO - Loamy Plains
Hydric soil rating: No
Custom Soil Resource Report
15
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.
K Factor, Whole Soil
Erosion factor K indicates the susceptibility of a soil to sheet and rill erosion by
water. Factor K is one of six factors used in the Universal Soil Loss Equation
(USLE) and the Revised Universal Soil Loss Equation (RUSLE) to predict the
average annual rate of soil loss by sheet and rill erosion in tons per acre per year.
The estimates are based primarily on percentage of silt, sand, and organic matter
and on soil structure and saturated hydraulic conductivity (Ksat). Values of K range
from 0.02 to 0.69. Other factors being equal, the higher the value, the more
susceptible the soil is to sheet and rill erosion by water.
"Erosion factor Kw (whole soil)" indicates the erodibility of the whole soil. The
estimates are modified by the presence of rock fragments.
16
Table—Hydrologic Soil Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
35 Fort Collins loam, 0 to 3
percent slopes
C 3.4 26.8%
74 Nunn clay loam, 1 to 3
percent slopes
C 9.4 73.2%
Totals for Area of Interest 12.9 100.0%
Rating Options—Hydrologic Soil Group
Aggregation Method: Dominant Condition
Component Percent Cutoff: None Specified
Tie-break Rule: Higher
Custom Soil Resource Report
23
National Flood Hazard Layer FIRMette
0 500 1,000 1,500 2,000250
Feet
Ü
SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT
SPECIAL FLOOD
HAZARD AREAS
Without Base Flood Elevation (BFE)
Zone A, V, A99
With BFE or DepthZone AE, AO, AH, VE, AR
Regulatory Floodway
0.2% Annual Chance Flood Hazard, Areas
of 1% annual chance flood with average
depth less than one foot or with drainage
areas of less than one square mileZone X
Future Conditions 1% Annual
Chance Flood HazardZone X
Area with Reduced Flood Risk due to
Levee. See Notes.Zone X
Area with Flood Risk due to LeveeZone D
NO SCREEN Area of Minimal Flood Hazard Zone X
Area of Undetermined Flood HazardZone 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 map complies with FEMA's standards for the use of
digital flood maps if it is not void as described below.
The basemap shown complies with FEMA's basemap
accuracy standards
The flood hazard information is derived directly from the
authoritative NFHL web services provided by FEMA. This map
was exported on 2/4/2021 at 5:35 PM and does not
reflect changes or amendments subsequent to this date and
time. The NFHL and effective information may change or
become superseded by new data over time.
This map image is void if the one or more of the following map
elements do not appear: basemap imagery, flood zone labels,
legend, scale bar, map creation date, community identifiers,
FIRM panel number, and FIRM effective date. Map images for
unmapped and unmodernized areas cannot be used for
regulatory purposes.
Legend
OTHER AREAS OF
FLOOD HAZARD
OTHER AREAS
GENERAL
STRUCTURES
OTHER
FEATURES
MAP PANELS
8
B 20.2
The pin displayed on the map is an approximate
point selected by the user and does not represent
an authoritative property location.
1:6,000
105°5'1"W 40°31'18"N
105°4'23"W 40°30'51"N
Basemap: USGS National Map: Orthoimagery: Data refreshed October, 2020
Project Site
APPENDIX B Fairway Lane Apartments – Fort Collins, CO
20065
FORT COLLINS STORMWATER CRITERIA MANUAL Hydrology Standards (Ch. 5)
2.0 Runoff Methodologies
3.1 Rational Formula
Page 3
2.0 Runoff Methodologies
There are two runoff analysis methodologies that are approved by the City: the Rational Method and
the Stormwater Management Model (SWMM). In general, the chosen methodology should follow the
basin size limitations listed in Table 2.0-1 below. SWMM must also be used to assess the performance of
multiple detention basins in parallel or in series in a particular watershed. The City is the determining
authority with respect to the appropriate methodology to use under uncertain circumstances. Please
note that the Colorado Urban Hydrograph Procedure (CUHP) is not allowed to be utilized for hydrology
analysis for Fort Collins area projects because this procedure is calibrated using Denver/Boulder rainfall
data.
Table 2.0-1: Runoff Calculation Method
Project Size Runoff Calculation Method
< 5 acres Rational Method Required
5-20 acres Rational Method or SWMM Accepted
≥ 20 acres SWMM Required
Reference: Drainage Report submittal requirements must be prepared in accordance with
the criteria set forth in Chapter 2: Development Submittal Requirements.
3.0 Rational Method
3.1 Rational Formula
The methodology and theory behind the Rational Method is not covered in this Manual as this subject is
well described in many hydrology reference books. However, the Rational Method procedure is
generally provided in the following sections. Runoff coefficient calculations, rainfall data, and the time of
concentration formula are specific to the City and are included below.
The Rational Formula is represented by the following equation:
𝐐𝐐=𝐂𝐂𝐂𝐂𝐂𝐂 Equation 5-1
Where: Q = Peak Rate of Runoff, cfs
C = Runoff Coefficient, dimensionless
I = Rainfall Intensity, in/hr
A = Area of the Basin or Sub-basin, acres
FORT COLLINS STORMWATER CRITERIA MANUAL Hydrology Standards (Ch. 5)
3.0 Rational Method
3.2 Runoff Coefficients
Page 4
3.2 Runoff Coefficients
Runoff coefficients used for the Rational Method are determined based on either overall land use or
surface type across the drainage area. For Overall Drainage Plan (ODP) submittals, when surface types
may not yet be known, land use shall be used to estimate flow rates and volumes. Table 3.2-1 lists the
runoff coefficients for common types of land uses in the City.
Table 3.2-1. Zoning Classification - Runoff Coefficients
Land Use Runoff Coefficient (C)
Residential
Urban Estate 0.30
Low Density 0.55
Medium Density 0.65
High Density 0.85
Commercial
Commercial 0.85
Industrial 0.95
Undeveloped
Open Lands, Transition 0.20
Greenbelts, Agriculture 0.20
Reference: For further guidance regarding zoning classifications, refer to the Land Use
Code, Article 4.
For a Project Development Plan (PDP) or Final Plan (FP) submittals, runoff coefficients must be based on
the proposed land surface types. Since the actual runoff coefficients may be different from those
specified in Table 3.2-1, Table 3.2-2 lists coefficients for the specific types of land surfaces.
FORT COLLINS STORMWATER CRITERIA MANUAL Hydrology Standards (Ch. 5)
3.0 Rational Method
3.2 Runoff Coefficients
Page 5
Table 3.2-2. Surface Type - Runoff Coefficients
Surface Type Runoff Coefficients
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
3.2.1 Composite Runoff Coefficients
Drainage sub-basins are frequently composed of land that has multiple surface types or zoning
classifications. In such cases a composite runoff coefficient must be calculated for any given drainage
sub-basin.
The composite runoff coefficient is obtained using the following formula:
( )
t
n
i
ii
A
xAC
C
∑
==1 Equation 5-2
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
3.2.2 Runoff Coefficient Frequency Adjustment Factor
The runoff coefficients provided in Table 3.2-1 and Table 3.2-2 are appropriate for use with the 2-year
storm event. For any analysis of storms with higher intensities, an adjustment of the runoff coefficient is
required due to the lessening amount of infiltration, depression retention, evapotranspiration and other
losses that have a proportionally smaller effect on high-intensity storm runoff. This adjustment is
FORT COLLINS STORMWATER CRITERIA MANUAL Hydrology Standards (Ch. 5)
3.0 Rational Method
3.3 Time of Concentration
Page 6
applied to the composite runoff coefficient. These frequency adjustment factors, Cf, are found in Table
3.2-3.
Table 3.2-3. Frequency Adjustment Factors
Storm Return Period
(years)
Frequency Adjustment
Factor (Cf)
2, 5, 10 1.00
25 1.10
50 1.20
100 1.25
3.3 Time of Concentration
3.3.1 Overall Equation
The next step to approximate runoff using the Rational Method is to estimate the Time of
Concentration, Tc, or the time for water to flow from the most remote part of the drainage sub-basin to
the design point under consideration.
The Time of Concentration is represented by the following equation:
𝐓𝐓𝐜𝐜=𝐓𝐓𝐢𝐢+𝐓𝐓𝐭𝐭 Equation 5-3
Where: Tc = Total Time of Concentration, minutes
Ti = Initial or Overland Flow Time of Concentration, minutes
Tt = Channelized Flow in Swale, Gutter or Pipe, minutes
3.3.2 Overland Flow Time
Overland flow, Ti, can be determined by the following equation:
𝐓𝐓𝐢𝐢=𝟏𝟏.𝟖𝟖𝟖𝟖(𝟏𝟏.𝟏𝟏−𝐂𝐂𝐂𝐂𝐂𝐂𝐟𝐟)√𝐋𝐋√𝐒𝐒𝟑𝟑 Equation 3.3-2
Where: C = Runoff Coefficient, dimensionless
Cf = Frequency Adjustment Factor, dimensionless
L = Length of Overland Flow, feet
S = Slope, percent
CXCF
PRODUCT OF CXCF
CANNOT EXCEED THE
VALUE OF 1
OVERLAND FLOW LENGTH
L=200’ MAX IN DEVELOPED AREAS
L=500’ MAX IN UNDEVELOPED
AREAS
FORT COLLINS STORMWATER CRITERIA MANUAL Hydrology Standards (Ch. 5)
3.0 Rational Method
3.4 Intensity-Duration-Frequency Curves for Rational Method
Page 7
3.3.3 Channelized Flow Time
Travel time in a swale, gutter or storm pipe is considered “channelized” or “concentrated” flow and can
be estimated using the Manning’s Equation:
𝐕𝐕= 𝟏𝟏.𝟒𝟒𝟒𝟒𝐧𝐧 𝐑𝐑𝟐𝟐/𝟑𝟑𝐒𝐒𝟏𝟏/𝟐𝟐 Equation 5-4
Where: V = Velocity, feet/second
n = Roughness Coefficient, dimensionless
R = Hydraulic Radius, feet (Hydraulic Radius = area / wetted perimeter, feet)
S = Longitudinal Slope, feet/feet
And:
𝐓𝐓𝐭𝐭=𝐋𝐋𝐕𝐕𝐂𝐂𝐕𝐕𝐕𝐕 Equation 5-5
3.3.4 Total Time of Concentration
A minimum Tc of 5 minutes is required. The maximum Tc
allowed for the most upstream design point shall be
calculated using the following equation:
𝐓𝐓𝐜𝐜=𝐋𝐋𝟏𝟏𝟖𝟖𝐕𝐕+𝟏𝟏𝐕𝐕 Equation 3.3-5
The Total Time of Concentration, Tc, is the lesser of the
values of Tc calculated using Tc = Ti + Tt or the equation
listed above.
3.4 Intensity-Duration-Frequency Curves for Rational Method
The two-hour rainfall Intensity-Duration-Frequency curves for use with the Rational Method is provided
in Table 3.4-1 and Figure 3.4-1.
TC
• A MINIMUM TC OF 5
MINUTES IS REQUIRED IN
ALL CASES.
• A MAXIMUM TC OF 5
MINUTES IS TYPICAL FOR
SMALLER, URBAN PROJECTS.
FORT COLLINS STORMWATER CRITERIA MANUAL Hydrology Standards (Ch. 5)
3.0 Rational Method
3.4 Intensity-Duration-Frequency Curves for Rational Method
Page 8
Table 3.4-1. IDF Table for Rational Method
Duration
(min)
Intensity
2-year
(in/hr)
Intensity
10-year
(in/hr)
Intensity
100-year
(in/hr)
Duration
(min)
Intensity
2-year
(in/hr)
Intensity
10-year
(in/hr)
Intensity
100-year
(in/hr)
5 2.85 4.87 9.95
39 1.09 1.86 3.8
6 2.67 4.56 9.31
40 1.07 1.83 3.74
7 2.52 4.31 8.80
41 1.05 1.80 3.68
8 2.40 4.10 8.38
42 1.04 1.77 3.62
9 2.30 3.93 8.03
43 1.02 1.74 3.56
10 2.21 3.78 7.72
44 1.01 1.72 3.51
11 2.13 3.63 7.42
45 0.99 1.69 3.46
12 2.05 3.50 7.16
46 0.98 1.67 3.41
13 1.98 3.39 6.92
47 0.96 1.64 3.36
14 1.92 3.29 6.71
48 0.95 1.62 3.31
15 1.87 3.19 6.52
49 0.94 1.6 3.27
16 1.81 3.08 6.30
50 0.92 1.58 3.23
17 1.75 2.99 6.10
51 0.91 1.56 3.18
18 1.70 2.90 5.92
52 0.9 1.54 3.14
19 1.65 2.82 5.75
53 0.89 1.52 3.10
20 1.61 2.74 5.60
54 0.88 1.50 3.07
21 1.56 2.67 5.46
55 0.87 1.48 3.03
22 1.53 2.61 5.32
56 0.86 1.47 2.99
23 1.49 2.55 5.20
57 0.85 1.45 2.96
24 1.46 2.49 5.09
58 0.84 1.43 2.92
25 1.43 2.44 4.98
59 0.83 1.42 2.89
26 1.4 2.39 4.87
60 0.82 1.4 2.86
27 1.37 2.34 4.78
65 0.78 1.32 2.71
28 1.34 2.29 4.69
70 0.73 1.25 2.59
29 1.32 2.25 4.60
75 0.70 1.19 2.48
30 1.30 2.21 4.52
80 0.66 1.14 2.38
31 1.27 2.16 4.42
85 0.64 1.09 2.29
32 1.24 2.12 4.33
90 0.61 1.05 2.21
33 1.22 2.08 4.24
95 0.58 1.01 2.13
34 1.19 2.04 4.16
100 0.56 0.97 2.06
35 1.17 2.00 4.08
105 0.54 0.94 2.00
36 1.15 1.96 4.01
110 0.52 0.91 1.94
37 1.16 1.93 3.93
115 0.51 0.88 1.88
38 1.11 1.89 3.87
120 0.49 0.86 1.84
FORT COLLINS STORMWATER CRITERIA MANUAL Hydrology Standards (Ch. 5)
3.0 Rational Method
3.4 Intensity-Duration-Frequency Curves for Rational Method
Page 9
Figure 3.4-1. Rainfall IDF Curve – Fort Collins
FORT COLLINS STORMWATER CRITERIA MANUAL Detention (Ch. 6)
2.0 Water Quantity Detention
2.2 SWMM
Page 6
Table 2.1-1: Detention Calculation Method
Project Size * Detention Calculation Method
< 5 acres Modified FAA Required
5-20 acres Modified FAA or SWMM Accepted
≥20 acres SWMM Required
*Project Size must include any offsite runoff that is tributary to the subject site
Note about the UDFCD Manual: Because of the Master Drainage Plans detention
requirements, the City does not allow for detention basins to be designed with the “full-
spectrum detention” method that is described in the UDFCD Manual.
2.2 SWMM
For project sites equal to or greater than 20 acres, the use of a Stormwater Management Model
(SWMM) is required.
If there are upstream detention facilities within the watershed that contribute and route runoff into the
site being designed, hydrograph routing methods must be employed to allow for the upstream facilities
to be included in the overall SWMM model.
Reference: The theory and methodology for reservoir routing is not covered in this Manual
as this subject is well described in many hydrology reference books.
2.3 Modified FAA Procedure
The Modified FAA Procedure (1966) detention sizing method as modified by Guo (1999a), provides a
reasonable estimate of volume requirements for detention facilities. This method provides sizing for one
level of peak control only and not for multi-stage control facilities.
The input required for this Modified FAA volume calculation procedure includes:
A = area of the catchment tributary to the detention facility (acres)
C = runoff coefficient
Qout = allowable maximum release rate from the detention facility (cfs)
Tc = time of concentration for the tributary catchment (minutes)
I = rainfall intensity (inches/hour) at the site taken from Chapter 4: Hydrology Standards, for the
relevant return frequency storms
The calculations are best set up in a tabular (spreadsheet) form with each 5-minute increment in
duration being entered in rows and the following variables being entered, or calculated, in each column:
1) Storm Duration Time, T (minutes), up to 120 minutes
FORT COLLINS STORMWATER CRITERIA MANUAL Detention (Ch. 6)
2.0 Water Quantity Detention
2.4 Detention Basin Volume
Page 7
2) Rainfall Intensity, I (inches per hour)
3) Inflow volume, Vi (cubic feet), calculated as the cumulative volume at the given storm
duration using the equation:
Vi = CIA (60T) Equation 6-1
4) Calculated outflow volume, Vo, (cubic feet), given the maximum allowable release rate,
Qout (cfs), over the duration T:
Vo= Qout (60 T) Equation 6-2
5) Required detention volume, Vs (cubic feet), calculated using the equation:
Vs = Vi – Vo Equation 6-3
The value of Vs increases with time, reaches a maximum value, and then starts to decrease. The
maximum value of Vs is the required detention volume for the detention facility.
Note about UDFCD Manual: Please note that the UDFCD excel-based spreadsheets are not
allowed to be used to calculate required detention volumes because they utilize Denver
region rainfall data. The Design Engineer will be required to establish their own
spreadsheet for calculating basin volume requirements based on the Modified FAA
Procedure documented above using Fort Collins IDF curves.
2.4 Detention Basin Volume
2.4.1 Stage-Storage
A relationship between the water surface elevation and detention basin volume, commonly referred to
as a “stage-storage” curve, needs to be developed. This relationship, in conjunction with the “stage-
discharge” relationship will provide the required detention volume. An initial detention basin design
must be created and a “stage-storage” curve developed that corresponds to the design.
The available detention volume shall be based on the following formula:
𝐕𝐕=𝐃𝐃𝟑𝟑�𝐀𝐀+𝐁𝐁+√𝐀𝐀𝐁𝐁� Equation 6-4
Where V = Volume between two contours, ft3
D = Depth between contours, feet
A = Area of bottom contour, ft2
B = Area of top contour, ft2
Fairway Lane ApartmentsFort Collins, ColoradoLAND USE AND IMPERVIOUSNESS12/14/202120065Surface TypeRunoff Coefficients% ImperviousAsphalt0.95100%2-Year Cf1.00Concrete 0.95 100%10-Year Cf1.00Rooftop0.9590%100-Year Cf1.25Gravel0.5040%Landscape < 2%0.202%Landscape 2-7%0.202%BASIN IMPERVIOUS CALCSBasins Conveying to On-Site Detention Basin to NorthTotal Area, A Total Area, A2-Year 10-Year 100-Year %Basin Description sf Acres Asphalt/Concrete Rooftop Landscape Composite Composite Composite Composite IA Soil TypeDesign PointArea (sf) Area (sf) Area (sf) Runoff Coefficient Runoff Coefficient Runoff Coefficient Impervious, I (A,B,C,D)1 B-1 24,8510.578,097 10,487 6,267 0 0.76 0.76 0.9571% 0.41C2 B-2 43,8911.0118,198 9,782 15,911 0 0.68 0.68 0.8562% 0.63C3 B-3 50,7791.1720,669 14,533 15,577 0 0.72 0.72 0.9067% 0.78C4 B-4 40,4010.9313,411 10,748 14,743 1,499 0.66 0.66 0.8259% 0.55C5 B-5 34,6920.8023,441 0 11,251 0 0.71 0.71 0.8868% 0.54C6 B-6 10,7430.256,645 746 3,121 231 0.72 0.72 0.9070% 0.17C7 B-7 34,0800.7818,993 10,321 4,767 0 0.85 0.85 1.0083% 0.65C8 B-8 29,4630.6820,449 6,132 2,882 0 0.88 0.88 1.0088% 0.60C9 B-9 7,4880.174,924 0 2,564 0 0.69 0.69 0.8766% 0.11C10B-1022,5050.526,5135,5979,6497460.610.610.7754%0.28C11 B-11 38,5720.8914,442 14,926 9,205 0 0.77 0.77 0.9673% 0.64C12 B-12 27,4890.6312,450 7,271 7,768 0 0.74 0.74 0.9270% 0.44C13 B-13 27,8380.6414,671 2,501 10,666 0 0.66 0.66 0.8362% 0.39C14 B-14 11,7170.278,706 0 3,010 1 0.76 0.76 0.9575% 0.20C15 B-15 60,1111.386,312 0 53,799 0 0.28 0.28 0.3512% 0.17C16 B-16 3,4360.08300 0 3,136 0 0.27 0.27 0.3311% 0.01C17 B-17 3,3950.08200 0 3,195 0 0.24 0.24 0.318% 0.01CO1 OS-1 11,8110.273,970 0 7,841 0 0.45 0.45 0.5735% 0.09CO2OS-25,2190.124,286093300.820.821.0082%0.10CGravel Area (sf)Basins Fort Collins Rational Calculations_2-10-100-Yr_.xlsxComposite 100-Yr RunoffCoefficient = 0.82(contributory to detention)
Fairway Lane ApartmentsFort Collins, Colorado12/14/202120065Note:Assumed C-value for flow over grassy surfaces is 0.25 (0.31 for 100-yr)Assumed C-value for flow over hard surfaces is 0.95 (1.00 for 100-yr)TIME OF CONCENTRATION CALCULATIONS INITIAL FLOW - Ti CHANNELIZED FLOW - TtC*Cf C*Cf C*Cf INIT. INIT. Trvl 1 Trvl 1 Trvl 12-Yr Tc = 10-Yr Tc = 100-Yr Tc =BASIN Is Length 2-yr Cf= 10-yr Cf= 100-yr Cf= L1 S1 Ti 2-yr Ti 10-yr Ti 100-yr L 2 V T2 (2yr Ti +Tt) (10yr Ti +Tt) (100yr Ti +Tt)Design Point >200' ?Flow path material 1 1 1.25(ft) (%) (min) (min) (min) (ft) (f/s) (min) (min) (min) (min)1NO Hard Surface 2 0.95 0.95 1.00 150.00 3.5% 2.27 2.27 1.51 50.0 0.0 -21.55.0 5.0 5.02NO Hard Surface 2 0.95 0.95 1.00 34.00 0.9% 1.71 1.71 1.14 290.0 0.0 -98.15.0 5.0 5.03NO Hard Surface 2 0.95 0.95 1.00 113.00 3.0% 2.07 2.07 1.38 448.5 2.2 3.45.5 5.5 5.04NO Hard Surface 2 0.95 0.95 1.00 102.00 1.2% 2.64 2.64 1.76 99.0 3.9 0.45.0 5.0 5.05NO Hard Surface 2 0.95 0.95 1.00 150.00 1.1% 3.30 3.30 2.20 47.0 5.0 0.25.0 5.0 5.06NO Hard Surface 2 0.95 0.95 1.00 160.00 3.0% 2.46 2.46 1.64 0.0 0.0 0.05.0 5.0 5.07NO Hard Surface 2 0.95 0.95 1.00 51.00 3.7% 1.30 1.30 0.87 0.0 0.0 0.05.0 5.0 5.08NO Hard Surface 0.95 0.95 1.00 91.00 3.1% 1.84 1.84 1.22 0.0 0.0 0.05.0 5.0 5.09NO Hard Surface 0.95 0.95 1.00 125.00 1.8% 2.59 2.59 1.73 0.0 0.0 0.05.0 5.0 5.010NO Hard Surface 0.95 0.95 1.00 95.00 5.2% 1.57 1.57 1.05 0.0 0.0 0.05.0 5.0 5.011NO Hard Surface 0.95 0.95 1.00 75.00 2.2% 1.87 1.87 1.25 0.0 0.0 0.05.0 5.0 5.012NO Hard Surface 0.95 0.95 1.00 88.00 1.6% 2.25 2.25 1.50 0.0 0.0 0.05.0 5.0 5.013NO Hard Surface 0.95 0.95 1.00 200.00 1.5% 3.47 3.47 2.31 0.0 0.0 0.05.0 5.0 5.014NO Hard Surface 0.95 0.95 1.00 114.00 1.5% 2.62 2.62 1.75 0.0 0.0 0.05.0 5.0 5.015NO Hard Surface 0.95 0.95 1.00 92.00 14.1% 1.11 1.11 0.74 0.0 0.0 0.05.0 5.0 5.016NO Hard Surface 0.95 0.95 1.00 57.00 1.0% 2.14 2.14 1.43 0.0 0.0 0.05.0 5.0 5.017NO Hard Surface 0.95 0.95 1.00 60.00 0.7% 2.47 2.47 1.64 0.0 0.0 0.05.0 5.0 5.0O1NO Hard Surface 0.95 0.95 1.00 25.00 1.0% 1.40 1.40 0.94 0.0 0.0 0.05.0 5.0 5.0O2NO Hard Surface 0.95 0.95 1.00 25.00 4.0% 0.88 0.88 0.59 0.0 0.0 0.05.0 5.0 5.0TRVL 2Basins Fort Collins Rational Calculations_2-10-100-Yr_.xlsx
Fairway Lane ApartmentsFort Collins, Colorado12/14/202120065PEAK FLOW CALCULATIONTypeAREA C2 C10 C100 2-Yr Tc* 10-Yr Tc* 100-Yr Tc* I 2 I 10 I 100 Q Q QBASIN2-yr 10-yr 100-yrDesign Point(acres) (min) (min) (min) (in/hr) (in/hr) (in/hr) (cfs) (cfs) (cfs)1 B-1 0.57 0.76 0.76 0.95 5.0 5.0 5.0 2.85 4.87 9.95 1.24 2.11 5.402 B-2 1.01 0.68 0.68 0.85 5.0 5.0 5.0 2.85 4.87 9.95 1.95 3.33 8.503 B-3 1.17 0.72 0.72 0.90 5.5 5.5 5.0 2.85 4.87 9.95 2.39 4.09 10.444 B-4 0.93 0.66 0.66 0.82 5.0 5.0 5.0 2.85 4.87 9.95 1.74 2.98 7.615 B-5 0.80 0.71 0.71 0.88 5.0 5.0 5.0 2.85 4.87 9.95 1.60 2.74 7.006 B-6 0.25 0.72 0.72 0.90 5.0 5.0 5.0 2.85 4.87 9.95 0.51 0.87 2.227 B-7 0.78 0.85 0.85 1.00 5.0 5.0 5.0 2.85 4.87 9.95 1.88 3.22 7.788 B-8 0.68 0.88 0.88 1.00 5.0 5.0 5.0 2.85 4.87 9.95 1.69 2.89 6.739 B-9 0.17 0.69 0.69 0.87 5.0 5.0 5.0 2.85 4.87 9.95 0.34 0.58 1.4810 B-10 0.52 0.61 0.61 0.77 5.0 5.0 5.0 2.85 4.87 9.95 0.90 1.54 3.9411 B-11 0.89 0.77 0.77 0.96 5.0 5.0 5.0 2.85 4.87 9.95 1.95 3.32 8.4912 B-12 0.63 0.74 0.74 0.92 5.0 5.0 5.0 2.85 4.87 9.95 1.33 2.27 5.7913 B-13 0.64 0.66 0.66 0.83 5.0 5.0 5.0 2.85 4.87 9.95 1.21 2.06 5.2714 B-14 0.27 0.76 0.76 0.95 5.0 5.0 5.0 2.85 4.87 9.95 0.58 0.99 2.5315 B-15 1.38 0.28 0.28 0.35 5.0 5.0 5.0 2.85 4.87 9.95 1.10 1.87 4.7816 B-16 0.08 0.27 0.27 0.33 5.0 5.0 5.0 2.85 4.87 9.95 0.06 0.10 0.2617 B-17 0.08 0.24 0.24 0.31 5.0 5.0 5.0 2.85 4.87 9.95 0.05 0.09 0.24O1 OS-1 0.27 0.45 0.45 0.57 5.0 5.0 5.0 2.85 4.87 9.95 0.35 0.60 1.52O2OS-20.120.820.821.005.05.05.02.854.879.950.280.481.19* If time of concentration was less than 5 minutes, 5 minutes was used.Sub-basinIntensitiesBasin CharacteristicsBasins Fort Collins Rational Calculations_2-10-100-Yr_.xlsx
APPENDIX C Fairway Lane Apartments – Fort Collins, CO
20065
Version 4.06 Released August 2018Worksheet ProtectedINLET NAMEINLET A3 & C1INLET A5INLET A7INLET A8INLET B1INLET B2 & B3URBAN URBAN URBAN URBAN URBAN URBANSTREET STREET STREET STREET STREET STREETIn Sump On Grade On Grade On Grade On Grade On GradeCDOT/Denver 13 Combination CDOT/Denver 13 Combination CDOT/Denver 13 Combination CDOT/Denver 13 Combination CDOT/Denver 13 Valley Grate CDOT/Denver 13 CombinationUSER-DEFINED INPUTUser-Defined Design Flows0.61.72.43.21.71.92.57.610.613.97.47.9User-Defined INLET A7 INLET A8 INLET A9 INLET B2 & B3 INLET B51.00.60.10.20.00.115.79.14.31.91.41.2Watershed CharacteristicsWatershed ProfileMinor Storm Rainfall InputMajor Storm Rainfall InputCALCULATED OUTPUT1.62.42.53.41.71.918.216.614.815.88.89.0N/A0.50.60.10.40.0N/A10.59.14.34.61.4Minor Storm (Calculated) Analysis of Flow TimeN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AMajor Storm (Calculated) Analysis of Flow TimeN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/ASite Type (Urban or Rural)Calculated Local Peak Flow, QpOverland Flow Velocity, ViChannel Flow Velocity, VtOverland Flow Time, TiChannel Travel Time, TtCalculated Time of Concentration, TcRegional TcCalculated Local Peak Flow, QpCRecommended TcTc selected by UserDesign Rainfall Intensity, IC5Minor Total Design Peak Flow, Q (cfs)Major Total Design Peak Flow, Q (cfs)CC5Overland Flow Velocity, ViRecommended TcTc selected by UserDesign Rainfall Intensity, IMinor Flow Bypassed Downstream, Qb (cfs)Major Flow Bypassed Downstream, Qb (cfs)Channel Flow Velocity, VtOverland Flow Time, TiChannel Travel Time, TtCalculated Time of Concentration, TcRegional TcChannel Slope (ft/ft)Channel Length (ft)Design Storm Return Period, Tr (years)One-Hour Precipitation, P1 (inches)Design Storm Return Period, Tr (years)One-Hour Precipitation, P1 (inches)Overland Length (ft)INLET MANAGEMENTInlet Application (Street or Area)Hydraulic ConditionMinor QKnown (cfs)Major QKnown (cfs)Receive Bypass Flow from:Minor Bypass Flow Received, Qb (cfs)Major Bypass Flow Received, Qb (cfs)Subcatchment Area (acres)Percent ImperviousNRCS Soil TypeOverland Slope (ft/ft)Inlet TypeBypass (Carry-Over) Flow from Upstream
Version 4.06 Released August 2018Worksheet ProtectedINLET NAMEUSER-DEFINED INPUTUser-Defined Design FlowsWatershed CharacteristicsWatershed ProfileMinor Storm Rainfall InputMajor Storm Rainfall InputCALCULATED OUTPUTMinor Storm (Calculated) Analysis of Flow TimeMajor Storm (Calculated) Analysis of Flow TimeSite Type (Urban or Rural)Calculated Local Peak Flow, QpOverland Flow Velocity, ViChannel Flow Velocity, VtOverland Flow Time, TiChannel Travel Time, TtCalculated Time of Concentration, TcRegional TcCalculated Local Peak Flow, QpCRecommended TcTc selected by UserDesign Rainfall Intensity, IC5Minor Total Design Peak Flow, Q (cfs)Major Total Design Peak Flow, Q (cfs)CC5Overland Flow Velocity, ViRecommended TcTc selected by UserDesign Rainfall Intensity, IMinor Flow Bypassed Downstream, Qb (cfs)Major Flow Bypassed Downstream, Qb (cfs)Channel Flow Velocity, VtOverland Flow Time, TiChannel Travel Time, TtCalculated Time of Concentration, TcRegional TcChannel Slope (ft/ft)Channel Length (ft)Design Storm Return Period, Tr (years)One-Hour Precipitation, P1 (inches)Design Storm Return Period, Tr (years)One-Hour Precipitation, P1 (inches)Overland Length (ft)INLET MANAGEMENTInlet Application (Street or Area)Hydraulic ConditionMinor QKnown (cfs)Major QKnown (cfs)Receive Bypass Flow from:Minor Bypass Flow Received, Qb (cfs)Major Bypass Flow Received, Qb (cfs)Subcatchment Area (acres)Percent ImperviousNRCS Soil TypeOverland Slope (ft/ft)Inlet TypeBypass (Carry-Over) Flow from UpstreamINLET C6INLET C4INLET C2 & C3INLET B5INLET A9INLET E1URBAN URBAN URBAN URBAN URBAN URBANSTREET STREET STREET STREET STREET STREETOn Grade On Grade On Grade On Grade On Grade On GradeCDOT/Denver 13 Combination CDOT/Denver 13 Combination CDOT/Denver 13 Combination CDOT/Denver 13 Combination CDOT/Denver 13 Combination CDOT/Denver 13 Combination0.92.01.30.51.21.63.98.65.93.24.57.0No Bypass Flow Received INLET C6 INLET C4 No Bypass Flow Received No Bypass Flow Received User-Defined0.00.20.40.00.00.00.01.55.20.00.00.40.92.11.70.51.21.63.910.111.03.24.57.40.20.40.00.10.20.01.55.21.31.21.90.0N/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/A
Version 4.06 Released August 2018Worksheet ProtectedINLET NAMEUSER-DEFINED INPUTUser-Defined Design FlowsWatershed CharacteristicsWatershed ProfileMinor Storm Rainfall InputMajor Storm Rainfall InputCALCULATED OUTPUTMinor Storm (Calculated) Analysis of Flow TimeMajor Storm (Calculated) Analysis of Flow TimeSite Type (Urban or Rural)Calculated Local Peak Flow, QpOverland Flow Velocity, ViChannel Flow Velocity, VtOverland Flow Time, TiChannel Travel Time, TtCalculated Time of Concentration, TcRegional TcCalculated Local Peak Flow, QpCRecommended TcTc selected by UserDesign Rainfall Intensity, IC5Minor Total Design Peak Flow, Q (cfs)Major Total Design Peak Flow, Q (cfs)CC5Overland Flow Velocity, ViRecommended TcTc selected by UserDesign Rainfall Intensity, IMinor Flow Bypassed Downstream, Qb (cfs)Major Flow Bypassed Downstream, Qb (cfs)Channel Flow Velocity, VtOverland Flow Time, TiChannel Travel Time, TtCalculated Time of Concentration, TcRegional TcChannel Slope (ft/ft)Channel Length (ft)Design Storm Return Period, Tr (years)One-Hour Precipitation, P1 (inches)Design Storm Return Period, Tr (years)One-Hour Precipitation, P1 (inches)Overland Length (ft)INLET MANAGEMENTInlet Application (Street or Area)Hydraulic ConditionMinor QKnown (cfs)Major QKnown (cfs)Receive Bypass Flow from:Minor Bypass Flow Received, Qb (cfs)Major Bypass Flow Received, Qb (cfs)Subcatchment Area (acres)Percent ImperviousNRCS Soil TypeOverland Slope (ft/ft)Inlet TypeBypass (Carry-Over) Flow from UpstreamINLET D1User-DefinedURBANSTREETOn GradeCDOT/Denver 13 Combination0.31.5No Bypass Flow Received0.00.00.31.50.00.4N/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/AN/A
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =0.0 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.020
Height of Curb at Gutter Flow Line HCURB =6.00 inches
Distance from Curb Face to Street Crown TCROWN =26.0 ft
Gutter Width W =2.00 ft
Street Transverse Slope SX =0.020 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.000 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =26.0 26.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 12.0 inches
Check boxes are not applicable in SUMP conditions
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =SUMP SUMP cfs
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET A3 & C1
UD-Inlet_v4.06 (1).xlsm, INLET A3 & C1 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a' from above)alocal =2.00 2.00 inches
Number of Unit Inlets (Grate or Curb Opening)No = 6 6
Water Depth at Flowline (outside of local depression)Ponding Depth = 6.0 7.8 inches
Grate Information MINOR MAJOR
Length of a Unit Grate Lo (G) =3.00 3.00 feet
Width of a Unit Grate Wo =1.73 1.73 feet
Area Opening Ratio for a Grate (typical values 0.15-0.90)Aratio =0.43 0.43
Clogging Factor for a Single Grate (typical value 0.50 - 0.70)Cf (G) =0.50 0.50
Grate Weir Coefficient (typical value 2.15 - 3.60)Cw (G) =3.30 3.30
Grate Orifice Coefficient (typical value 0.60 - 0.80)Co (G) =0.60 0.60
Curb Opening Information MINOR MAJOR
Length of a Unit Curb Opening Lo (C) =3.00 3.00 feet
Height of Vertical Curb Opening in Inches Hvert =6.50 6.50 inches
Height of Curb Orifice Throat in Inches Hthroat =5.25 5.25 inches
Angle of Throat (see USDCM Figure ST-5)Theta = 0.00 0.00 degrees
Side Width for Depression Pan (typically the gutter width of 2 feet)Wp =2.00 2.00 feet
Clogging Factor for a Single Curb Opening (typical value 0.10)Cf (C) =0.10 0.10
Curb Opening Weir Coefficient (typical value 2.3-3.7)Cw (C) =3.70 3.70
Curb Opening Orifice Coefficient (typical value 0.60 - 0.70)Co (C) =0.66 0.66
Low Head Performance Reduction (Calculated)MINOR MAJOR
Depth for Grate Midwidth dGrate =0.523 0.669 ft
Depth for Curb Opening Weir Equation dCurb =0.33 0.48 ft
Combination Inlet Performance Reduction Factor for Long Inlets RFCombination =0.57 0.73
Curb Opening Performance Reduction Factor for Long Inlets RFCurb =0.79 0.88
Grated Inlet Performance Reduction Factor for Long Inlets RFGrate =0.57 0.73
MINOR MAJOR
Total Inlet Interception Capacity (assumes clogged condition)Qa =13.1 26.6 cfs
Inlet Capacity IS GOOD for Minor and Major Storms(>Q PEAK)Q PEAK REQUIRED =1.6 18.2 cfs
CDOT/Denver 13 Combination
INLET IN A SUMP OR SAG LOCATION
Version 4.06 Released August 2018
H-VertH-Curb
W
Lo (C)
Lo (G)
Wo
WP
CDOT/Denver 13 Combination
Override Depths
UD-Inlet_v4.06 (1).xlsm, INLET A3 & C1 12/15/2021, 11:31 AM
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =0.0 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.020
Height of Curb at Gutter Flow Line HCURB =8.00 inches
Distance from Curb Face to Street Crown TCROWN =26.0 ft
Gutter Width W =2.00 ft
Street Transverse Slope SX =0.020 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.015 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =26.0 26.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no)check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =18.0 18.0 cfs
Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET A5
UD-Inlet_v4.06 (1).xlsm, INLET A5 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a')aLOCAL =2.0 2.0 inches
Total Number of Units in the Inlet (Grate or Curb Opening)No = 2 2
Length of a Single Unit Inlet (Grate or Curb Opening)Lo =3.00 3.00 ft
Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo =1.73 1.73 ft
Clogging Factor for a Single Unit Grate (typical min. value = 0.5)Cf-G =0.50 0.50
Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1)Cf-C =0.10 0.10
Street Hydraulics: OK - Q < Allowable Street Capacity'MINOR MAJOR
Total Inlet Interception Capacity Q = 1.8 6.1 cfs
Total Inlet Carry-Over Flow (flow bypassing inlet)Qb =0.5 10.5 cfs
Capture Percentage = Qa/Qo =C% = 77 37 %
INLET ON A CONTINUOUS GRADE
Version 4.06 Released August 2018
CDOT/Denver 13 CombinationCDOT/Denver 13 Combination
UD-Inlet_v4.06 (1).xlsm, INLET A5 12/15/2021, 11:31 AM
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =0.0 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.020
Height of Curb at Gutter Flow Line HCURB =6.00 inches
Distance from Curb Face to Street Crown TCROWN =22.0 ft
Gutter Width W =2.00 ft
Street Transverse Slope SX =0.020 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.015 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =22.0 22.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no)check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =18.0 18.0 cfs
Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET A7
UD-Inlet_v4.06 (1).xlsm, INLET A7 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a')aLOCAL =2.0 2.0 inches
Total Number of Units in the Inlet (Grate or Curb Opening)No = 2 2
Length of a Single Unit Inlet (Grate or Curb Opening)Lo =3.00 3.00 ft
Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo =1.73 1.73 ft
Clogging Factor for a Single Unit Grate (typical min. value = 0.5)Cf-G =0.50 0.50
Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1)Cf-C =0.10 0.10
Street Hydraulics: OK - Q < Allowable Street Capacity'MINOR MAJOR
Total Inlet Interception Capacity Q = 1.9 5.8 cfs
Total Inlet Carry-Over Flow (flow bypassing inlet)Qb =0.6 9.1 cfs
Capture Percentage = Qa/Qo =C% = 76 39 %
INLET ON A CONTINUOUS GRADE
Version 4.06 Released August 2018
CDOT/Denver 13 CombinationCDOT/Denver 13 Combination
UD-Inlet_v4.06 (1).xlsm, INLET A7 12/15/2021, 11:31 AM
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =10.0 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.020
Height of Curb at Gutter Flow Line HCURB =6.00 inches
Distance from Curb Face to Street Crown TCROWN =26.0 ft
Gutter Width W =2.00 ft
Street Transverse Slope SX =0.025 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.020 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =26.0 26.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no)check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =17.9 17.9 cfs
Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET A8
UD-Inlet_v4.06 (1).xlsm, INLET A8 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a')aLOCAL =2.0 2.0 inches
Total Number of Units in the Inlet (Grate or Curb Opening)No = 4 4
Length of a Single Unit Inlet (Grate or Curb Opening)Lo =3.00 3.00 ft
Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo =1.73 1.73 ft
Clogging Factor for a Single Unit Grate (typical min. value = 0.5)Cf-G =0.50 0.50
Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1)Cf-C =0.10 0.10
Street Hydraulics: OK - Q < Allowable Street Capacity'MINOR MAJOR
Total Inlet Interception Capacity Q = 3.2 11.5 cfs
Total Inlet Carry-Over Flow (flow bypassing inlet)Qb =0.1 4.3 cfs
Capture Percentage = Qa/Qo =C% = 96 73 %
INLET ON A CONTINUOUS GRADE
Version 4.06 Released August 2018
CDOT/Denver 13 CombinationCDOT/Denver 13 Combination
UD-Inlet_v4.06 (1).xlsm, INLET A8 12/15/2021, 11:31 AM
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =0.0 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.020
Height of Curb at Gutter Flow Line HCURB =6.00 inches
Distance from Curb Face to Street Crown TCROWN =24.0 ft
Gutter Width W =2.00 ft
Street Transverse Slope SX =0.020 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.006 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =24.0 24.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no)check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =11.4 11.4 cfs
Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET B1
UD-Inlet_v4.06 (1).xlsm, INLET B1 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a')aLOCAL =2.0 2.0 inches
Total Number of Units in the Inlet (Grate or Curb Opening)No = 2 2
Length of a Single Unit Inlet (Grate or Curb Opening)Lo =3.00 3.00 ft
Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo =1.73 1.73 ft
Clogging Factor for a Single Unit Grate (typical min. value = 0.5)Cf-G =0.50 0.50
Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1)Cf-C =N/A N/A
Street Hydraulics: OK - Q < Allowable Street Capacity'MINOR MAJOR
Total Inlet Interception Capacity Q = 1.3 4.2 cfs
Total Inlet Carry-Over Flow (flow bypassing inlet)Qb =0.4 4.6 cfs
Capture Percentage = Qa/Qo =C% = 76 48 %
INLET ON A CONTINUOUS GRADE
Version 4.06 Released August 2018
CDOT/Denver 13 Valley GrateCDOT/Denver 13 Valley Grate
UD-Inlet_v4.06 (1).xlsm, INLET B1 12/15/2021, 11:31 AM
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =0.0 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.020
Height of Curb at Gutter Flow Line HCURB =6.00 inches
Distance from Curb Face to Street Crown TCROWN =26.0 ft
Gutter Width W =2.00 ft
Street Transverse Slope SX =0.020 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.015 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =26.0 26.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no)check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =18.0 18.0 cfs
Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET B2 & B3
UD-Inlet_v4.06 (1).xlsm, INLET B2 & B3 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a')aLOCAL =2.0 2.0 inches
Total Number of Units in the Inlet (Grate or Curb Opening)No = 4 4
Length of a Single Unit Inlet (Grate or Curb Opening)Lo =3.00 3.00 ft
Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo =1.73 1.73 ft
Clogging Factor for a Single Unit Grate (typical min. value = 0.5)Cf-G =0.50 0.50
Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1)Cf-C =0.10 0.10
Street Hydraulics: OK - Q < Allowable Street Capacity'MINOR MAJOR
Total Inlet Interception Capacity Q = 2.1 7.7 cfs
Total Inlet Carry-Over Flow (flow bypassing inlet)Qb =0.0 1.4 cfs
Capture Percentage = Qa/Qo =C% = 100 85 %
INLET ON A CONTINUOUS GRADE
Version 4.06 Released August 2018
CDOT/Denver 13 CombinationCDOT/Denver 13 Combination
UD-Inlet_v4.06 (1).xlsm, INLET B2 & B3 12/15/2021, 11:31 AM
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =0.0 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.020
Height of Curb at Gutter Flow Line HCURB =6.00 inches
Distance from Curb Face to Street Crown TCROWN =24.0 ft
Gutter Width W =2.00 ft
Street Transverse Slope SX =0.020 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.030 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =24.0 24.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =4.5 4.5 inches
Allow Flow Depth at Street Crown (leave blank for no)check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =9.5 9.5 cfs
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET C6
Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
UD-Inlet_v4.06 (1).xlsm, INLET C6 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a')aLOCAL =2.0 2.0 inches
Total Number of Units in the Inlet (Grate or Curb Opening)No = 2 2
Length of a Single Unit Inlet (Grate or Curb Opening)Lo =3.00 3.00 ft
Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo =1.73 1.73 ft
Clogging Factor for a Single Unit Grate (typical min. value = 0.5)Cf-G =0.50 0.50
Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1)Cf-C =0.10 0.10
Street Hydraulics: OK - Q < Allowable Street Capacity'MINOR MAJOR
Total Inlet Interception Capacity Q = 0.7 2.3 cfs
Total Inlet Carry-Over Flow (flow bypassing inlet)Qb =0.2 1.5 cfs
Capture Percentage = Qa/Qo =C% = 83 61 %
INLET ON A CONTINUOUS GRADE
Version 4.06 Released August 2018
CDOT/Denver 13 CombinationCDOT/Denver 13 Combination
UD-Inlet_v4.06 (1).xlsm, INLET C6 12/15/2021, 11:31 AM
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =0.0 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.020
Height of Curb at Gutter Flow Line HCURB =6.00 inches
Distance from Curb Face to Street Crown TCROWN =26.0 ft
Gutter Width W =2.00 ft
Street Transverse Slope SX =0.020 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.010 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =26.0 26.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no)check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =14.7 14.7 cfs
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET C4
Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
UD-Inlet_v4.06 (1).xlsm, INLET C4 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a')aLOCAL =2.0 2.0 inches
Total Number of Units in the Inlet (Grate or Curb Opening)No = 2 2
Length of a Single Unit Inlet (Grate or Curb Opening)Lo =3.00 3.00 ft
Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo =1.73 1.73 ft
Clogging Factor for a Single Unit Grate (typical min. value = 0.5)Cf-G =0.50 0.50
Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1)Cf-C =0.10 0.10
Street Hydraulics: OK - Q < Allowable Street Capacity'MINOR MAJOR
Total Inlet Interception Capacity Q = 1.7 5.0 cfs
Total Inlet Carry-Over Flow (flow bypassing inlet)Qb =0.4 5.2 cfs
Capture Percentage = Qa/Qo =C% = 82 49 %
INLET ON A CONTINUOUS GRADE
Version 4.06 Released August 2018
CDOT/Denver 13 CombinationCDOT/Denver 13 Combination
UD-Inlet_v4.06 (1).xlsm, INLET C4 12/15/2021, 11:31 AM
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =0.0 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.020
Height of Curb at Gutter Flow Line HCURB =6.00 inches
Distance from Curb Face to Street Crown TCROWN =24.0 ft
Gutter Width W =2.00 ft
Street Transverse Slope SX =0.020 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.010 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =24.0 24.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no)check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =14.7 14.7 cfs
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET C2 & C3
Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
UD-Inlet_v4.06 (1).xlsm, INLET C2 & C3 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a')aLOCAL =2.0 2.0 inches
Total Number of Units in the Inlet (Grate or Curb Opening)No = 4 4
Length of a Single Unit Inlet (Grate or Curb Opening)Lo =3.00 3.00 ft
Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo =1.73 1.73 ft
Clogging Factor for a Single Unit Grate (typical min. value = 0.5)Cf-G =0.50 0.50
Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1)Cf-C =0.10 0.10
Street Hydraulics: OK - Q < Allowable Street Capacity'MINOR MAJOR
Design Discharge for Half of Street (from Sheet Inlet Management )Qo =1.7 11.0 cfs
Water Spread Width T = 7.2 16.7 ft
Water Depth at Flowline (outside of local depression)d = 3.2 5.5 inches
Water Depth at Street Crown (or at TMAX)dCROWN =0.0 0.0 inches
Ratio of Gutter Flow to Design Flow Eo =0.738 0.358
Discharge outside the Gutter Section W, carried in Section Tx Qx =0.5 7.1 cfs
Discharge within the Gutter Section W Qw =1.3 3.9 cfs
Discharge Behind the Curb Face QBACK =0.0 0.0 cfs
Flow Area within the Gutter Section W AW =0.37 0.75 sq ft
Velocity within the Gutter Section W VW =3.4 5.2 fps
Water Depth for Design Condition dLOCAL =5.2 7.5 inches
Grate Analysis (Calculated)MINOR MAJOR
Total Length of Inlet Grate Opening L = 12.00 12.00 ft
Ratio of Grate Flow to Design Flow Eo-GRATE =0.691 0.324
Under No-Clogging Condition MINOR MAJOR
Minimum Velocity Where Grate Splash-Over Begins Vo =3.49 3.49 fps
Interception Rate of Frontal Flow Rf =1.00 0.97
Interception Rate of Side Flow Rx =0.88 0.79
Interception Capacity Qi =1.7 9.3 cfs
Under Clogging Condition MINOR MAJOR
Clogging Coefficient for Multiple-unit Grate Inlet GrateCoef = 1.88 1.88
Clogging Factor for Multiple-unit Grate Inlet GrateClog = 0.24 0.24
Effective (unclogged) Length of Multiple-unit Grate Inlet Le =9.18 9.18 ft
Minimum Velocity Where Grate Splash-Over Begins Vo =2.97 2.97 fps
Interception Rate of Frontal Flow Rf =1.00 0.92
Interception Rate of Side Flow Rx =0.79 0.66
Actual Interception Capacity Qa =1.6 8.2 cfs
Carry-Over Flow = Qo-Qa (to be applied to curb opening or next d/s inlet)Qb =0.1 2.8 cfs
Curb or Slotted Inlet Opening Analysis (Calculated)MINOR MAJOR
Equivalent Slope Se (based on grate carry-over) Se =0.128 0.072 ft/ft
Required Length LT to Have 100% Interception LT =1.69 11.30 ft
Under No-Clogging Condition MINOR MAJOR
Effective Length of Curb Opening or Slotted Inlet (minimum of L, LT)L = 1.69 11.30 ft
Interception Capacity Qi =0.3 1.7 cfs
Under Clogging Condition MINOR MAJOR
Clogging Coefficient CurbCoef = 1.25 1.25
Clogging Factor for Multiple-unit Curb Opening or Slotted Inlet CurbClog = 0.05 0.05
Effective (Unclogged) Length Le =11.63 11.63 ft
Actual Interception Capacity Qa =0.3 1.5 cfs
Carry-Over Flow = Qb(GRATE)-Qa Qb =0.0 1.3 cfs
Summary MINOR MAJOR
Total Inlet Interception Capacity Q = 1.9 9.7 cfs
Total Inlet Carry-Over Flow (flow bypassing inlet)Qb =0.0 1.3 cfs
Capture Percentage = Qa/Qo =C% = 100 88 %
INLET ON A CONTINUOUS GRADE
Version 4.06 Released August 2018
CDOT/Denver 13 CombinationCDOT/Denver 13 Combination
UD-Inlet_v4.06 (1).xlsm, INLET C2 & C3 12/15/2021, 11:31 AM
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =0.0 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.020
Height of Curb at Gutter Flow Line HCURB =6.00 inches
Distance from Curb Face to Street Crown TCROWN =12.0 ft
Gutter Width W =2.00 ft
Street Transverse Slope SX =0.030 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.040 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =12.0 12.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no)check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =13.4 13.4 cfs
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET B5
Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
UD-Inlet_v4.06 (1).xlsm, INLET B5 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a')aLOCAL =2.0 2.0 inches
Total Number of Units in the Inlet (Grate or Curb Opening)No = 2 2
Length of a Single Unit Inlet (Grate or Curb Opening)Lo =3.00 3.00 ft
Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo =1.73 1.73 ft
Clogging Factor for a Single Unit Grate (typical min. value = 0.5)Cf-G =0.50 0.50
Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1)Cf-C =0.10 0.10
Street Hydraulics: OK - Q < Allowable Street Capacity'MINOR MAJOR
Total Inlet Interception Capacity Q = 0.4 2.0 cfs
Total Inlet Carry-Over Flow (flow bypassing inlet)Qb =0.1 1.2 cfs
Capture Percentage = Qa/Qo =C% = 90 63 %
INLET ON A CONTINUOUS GRADE
Version 4.06 Released August 2018
CDOT/Denver 13 CombinationCDOT/Denver 13 Combination
UD-Inlet_v4.06 (1).xlsm, INLET B5 12/15/2021, 11:31 AM
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =0.0 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.020
Height of Curb at Gutter Flow Line HCURB =6.00 inches
Distance from Curb Face to Street Crown TCROWN =20.0 ft
Gutter Width W =2.00 ft
Street Transverse Slope SX =0.025 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.035 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =20.0 20.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no)check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =15.6 15.6 cfs
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET A9
Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
UD-Inlet_v4.06 (1).xlsm, INLET A9 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a')aLOCAL =2.0 2.0 inches
Total Number of Units in the Inlet (Grate or Curb Opening)No = 2 2
Length of a Single Unit Inlet (Grate or Curb Opening)Lo =3.00 3.00 ft
Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo =1.73 1.73 ft
Clogging Factor for a Single Unit Grate (typical min. value = 0.5)Cf-G =0.50 0.50
Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1)Cf-C =0.10 0.10
Street Hydraulics: OK - Q < Allowable Street Capacity'MINOR MAJOR
Total Inlet Interception Capacity Q = 1.0 2.5 cfs
Total Inlet Carry-Over Flow (flow bypassing inlet)Qb =0.2 1.9 cfs
Capture Percentage = Qa/Qo =C% = 84 57 %
INLET ON A CONTINUOUS GRADE
Version 4.06 Released August 2018
CDOT/Denver 13 CombinationCDOT/Denver 13 Combination
UD-Inlet_v4.06 (1).xlsm, INLET A9 12/15/2021, 11:31 AM
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =10.5 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.015
Height of Curb at Gutter Flow Line HCURB =6.00 inches
Distance from Curb Face to Street Crown TCROWN =45.0 ft
Gutter Width W =2.00 ft
Street Transverse Slope SX =0.020 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.015 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =30.0 45.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 8.0 inches
Allow Flow Depth at Street Crown (leave blank for no)check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =18.0 48.0 cfs
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET E1
Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
UD-Inlet_v4.06 (1).xlsm, INLET E1 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a')aLOCAL =2.0 2.0 inches
Total Number of Units in the Inlet (Grate or Curb Opening)No = 5 5
Length of a Single Unit Inlet (Grate or Curb Opening)Lo =3.00 3.00 ft
Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo =1.73 1.73 ft
Clogging Factor for a Single Unit Grate (typical min. value = 0.5)Cf-G =0.50 0.50
Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1)Cf-C =0.10 0.10
Street Hydraulics: OK - Q < Allowable Street Capacity'MINOR MAJOR
Total Inlet Interception Capacity Q = 1.8 7.4 cfs
Total Inlet Carry-Over Flow (flow bypassing inlet)Qb =0.0 0.0 cfs
Capture Percentage = Qa/Qo =C% = 100 99 %
INLET ON A CONTINUOUS GRADE
Version 4.06 Released August 2018
CDOT/Denver 13 CombinationCDOT/Denver 13 Combination
UD-Inlet_v4.06 (1).xlsm, INLET E1 12/15/2021, 11:31 AM
Project:
Inlet ID:
Gutter Geometry (Enter data in the blue cells)
Maximum Allowable Width for Spread Behind Curb TBACK =6.0 ft
Side Slope Behind Curb (leave blank for no conveyance credit behind curb)SBACK =0.020 ft/ft
Manning's Roughness Behind Curb (typically between 0.012 and 0.020)nBACK =0.015
Height of Curb at Gutter Flow Line HCURB =6.00 inches
Distance from Curb Face to Street Crown TCROWN =26.0 ft
Gutter Width W =1.00 ft
Street Transverse Slope SX =0.020 ft/ft
Gutter Cross Slope (typically 2 inches over 24 inches or 0.083 ft/ft)SW =0.083 ft/ft
Street Longitudinal Slope - Enter 0 for sump condition SO =0.040 ft/ft
Manning's Roughness for Street Section (typically between 0.012 and 0.020)nSTREET =0.015
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX =20.0 26.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX =6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no)check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow =24.6 24.6 cfs
Minor storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Major storm max. allowable capacity GOOD - greater than the design flow given on sheet 'Inlet Management'
Version 4.06 Released August 2018
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Enter Your Project Name Here
INLET D1
UD-Inlet_v4.06 (1).xlsm, INLET D1 12/15/2021, 11:31 AM
Design Information (Input)MINOR MAJOR
Type of Inlet Type =
Local Depression (additional to continuous gutter depression 'a')aLOCAL =2.0 2.0 inches
Total Number of Units in the Inlet (Grate or Curb Opening)No = 2 2
Length of a Single Unit Inlet (Grate or Curb Opening)Lo =3.00 3.00 ft
Width of a Unit Grate (cannot be greater than W, Gutter Width) Wo =1.73 1.73 ft
Clogging Factor for a Single Unit Grate (typical min. value = 0.5)Cf-G =0.50 0.50
Clogging Factor for a Single Unit Curb Opening (typical min. value = 0.1)Cf-C =0.10 0.10
Street Hydraulics: OK - Q < Allowable Street Capacity'MINOR MAJOR
Total Inlet Interception Capacity Q = 0.3 1.1 cfs
Total Inlet Carry-Over Flow (flow bypassing inlet)Qb =0.0 0.4 cfs
Capture Percentage = Qa/Qo =C% = 100 72 %
CDOT/Denver 13 Combination
INLET ON A CONTINUOUS GRADE
Version 4.06 Released August 2018
CDOT/Denver 13 Combination
UD-Inlet_v4.06 (1).xlsm, INLET D1 12/15/2021, 11:31 AM
APPENDIX D Fairway Lane Apartments – Fort Collins, CO
20065
0.82
2.16
10.82
Time (min)Intensity
(In/hr)Qin (cfs)Vin (ft3)Qout (cfs)Vout (ft3)
Volume Detained
(ft3)
Volume Detained
(acre-ft)
5 9.95 88.47 26540 2.16 649 25890 0.59
10 7.72 68.64 41183 2.16 1299 39885 0.92
15 6.52 57.97 52173 2.16 1948 50225 1.15
20 5.6 49.79 59748 2.16 2598 57151 1.31
25 4.98 44.28 66416 2.16 3247 63169 1.45
30 4.52 40.19 72338 2.16 3896 68442 1.57
35 4.08 36.28 76179 2.16 4546 71633 1.64
40 3.74 33.25 79806 2.16 5195 74611 1.71
45 3.46 30.76 83060 2.16 5844 77216 1.77
50 3.23 28.72 86155 2.16 6494 79661 1.83
55 3.03 26.94 88902 2.16 7143 81759 1.88
60 2.86 25.43 91543 2.16 7793 83750 1.92
65 2.71 24.09 93970 2.16 8442 85528 1.96
70 2.59 23.03 96717 2.16 9091 87626 2.01
75 2.48 22.05 99224 2.16 9741 89484 2.05
80 2.38 21.16 101572 2.16 10390 91182 2.09
85 2.29 20.36 103839 2.16 11039 92799 2.13
90 2.21 19.65 106106 2.16 11689 94417 2.17
95 2.13 18.94 107947 2.16 12338 95608 2.19
100 2.06 18.32 109894 2.16 12988 96906 2.22
105 2.00 17.78 112028 2.16 13637 98391 2.26
110 1.94 17.25 113841 2.16 14286 99555 2.29
115 1.88 16.72 115335 2.16 14936 100399 2.30
120 1.84 16.36 117789 2.16 15585 102204 2.35
Volume (ft^3)102,204
Detention requirements for Detention Pond for Major Storm (100-Yr)
Modified FAA Method
Runoff Coefficient
Total Detention @ 120 mins (Acre-ft) = 2.35Allowed Release Rate (cfs)
Area (B-1 - B-17) (Acres)
Project:
Basin ID:
Depth Increment = ft
Watershed Information Top of Micropool -- 0.00 -- -- -- 0 0.000
Selected BMP Type =EDB 4993 -- 0.75 -- -- -- 7,646 0.176 2,867 0.066
Watershed Area = 10.82 acres 4994 -- 1.75 -- -- -- 15,255 0.350 14,317 0.329
Watershed Length = 1,085 ft 4995 -- 2.75 -- -- -- 19,410 0.446 31,650 0.727
Watershed Length to Centroid = 500 ft 4996 -- 3.75 -- -- -- 22,737 0.522 52,723 1.210
Watershed Slope = 0.025 ft/ft 4997 -- 4.75 -- -- -- 25,008 0.574 76,596 1.758
Watershed Imperviousness = 60.80% percent crest 4998 -- 5.75 -- -- -- 27,251 0.626 102,725 2.358
Percentage Hydrologic Soil Group A = 0.0% percent top 4999 -- 6.75 -- -- -- 27,251 0.626 129,976 2.984
Percentage Hydrologic Soil Group B = 0.0% percent -- -- -- --
Percentage Hydrologic Soil Groups C/D = 100.0% percent -- -- -- --
Target WQCV Drain Time = 40.0 hours -- -- -- --
Location for 1-hr Rainfall Depths = User Input -- -- -- --
-- -- -- --
-- -- -- --
Optional User Overrides -- -- -- --
Water Quality Capture Volume (WQCV) = 0.215 acre-feet acre-feet -- -- -- --
Excess Urban Runoff Volume (EURV) = 0.632 acre-feet acre-feet -- -- -- --
2-yr Runoff Volume (P1 = 0.82 in.) = 0.404 acre-feet 0.82 inches -- -- -- --
5-yr Runoff Volume (P1 = 1.13 in.) = 0.623 acre-feet 1.13 inches -- -- -- --
10-yr Runoff Volume (P1 = 1.4 in.) = 0.849 acre-feet 1.40 inches -- -- -- --
25-yr Runoff Volume (P1 = 1.93 in.) = 1.353 acre-feet 1.93 inches -- -- -- --
50-yr Runoff Volume (P1 = 2.4 in.) = 1.787 acre-feet 2.40 inches -- -- -- --
100-yr Runoff Volume (P1 = 2.86 in.) = 2.238 acre-feet 2.86 inches -- -- -- --
500-yr Runoff Volume (P1 = 4.51 in.) = 3.808 acre-feet 4.51 inches -- -- -- --
Approximate 2-yr Detention Volume = 0.389 acre-feet -- -- -- --
Approximate 5-yr Detention Volume = 0.609 acre-feet -- -- -- --
Approximate 10-yr Detention Volume = 0.738 acre-feet -- -- -- --
Approximate 25-yr Detention Volume = 0.953 acre-feet -- -- -- --
Approximate 50-yr Detention Volume = 1.086 acre-feet -- -- -- --
Approximate 100-yr Detention Volume = 1.276 acre-feet -- -- -- --
-- -- -- --
Define Zones and Basin Geometry -- -- -- --
Zone 1 Volume (WQCV) = 0.215 acre-feet -- -- -- --
Zone 2 Volume (EURV - Zone 1) = 0.417 acre-feet -- -- -- --
Zone 3 Volume (100-year - Zones 1 & 2) = 0.643 acre-feet -- -- -- --
Total Detention Basin Volume = 1.276 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 -- -- -- --
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)
Fairway Lane Apartments
SE POND
MHFD-Detention, Version 4.04 (February 2021)
ExampleZone Configuration (Retention Pond)
MHFD-Detention_v4 04 (3).xlsm, Basin 12/14/2021, 8:01 PM
Project:
Basin ID:
Estimated Estimated
Stage (ft) Volume (ac-ft) Outlet Type
Zone 1 (WQCV) 1.40 0.215 Orifice Plate
Zone 2 (EURV) 2.54 0.417 Circular Orifice
Zone 3 (100-year) 3.88 0.643 Weir&Pipe (Restrict)
Total (all zones) 1.276
User Input: Orifice at Underdrain Outlet (typically used to drain WQCV in a Filtration BMP)Calculated Parameters for Underdrain
Underdrain Orifice Invert Depth = ft (distance below the filtration media surface) Underdrain Orifice Area =ft2
Underdrain Orifice Diameter = inches Underdrain Orifice Centroid = feet
User Input: Orifice Plate with one or more orifices or Elliptical Slot Weir (typically used to drain WQCV and/or EURV in a sedimentation BMP)Calculated Parameters for Plate
Invert of Lowest Orifice = 0.00 ft (relative to basin bottom at Stage = 0 ft) WQ Orifice Area per Row = 7.083E-03 ft2
Depth at top of Zone using Orifice Plate = 1.40 ft (relative to basin bottom at Stage = 0 ft) Elliptical Half-Width = N/A feet
Orifice Plate: Orifice Vertical Spacing = 4.00 inches Elliptical Slot Centroid = N/A feet
Orifice Plate: Orifice Area per Row = 1.02 sq. inches (diameter = 1-1/8 inches)Elliptical Slot Area = N/A ft2
User Input: Stage and Total Area of Each Orifice Row (numbered from lowest to highest)
Row 1 (required) Row 2 (optional) Row 3 (optional) Row 4 (optional) Row 5 (optional) Row 6 (optional) Row 7 (optional) Row 8 (optional)
Stage of Orifice Centroid (ft) 0.00 0.30 0.60 0.90 1.20
Orifice Area (sq. inches) 1.02 1.02 1.02 1.02 1.02
Row 9 (optional) Row 10 (optional) Row 11 (optional) Row 12 (optional) Row 13 (optional) Row 14 (optional) Row 15 (optional) Row 16 (optional)
Stage of Orifice Centroid (ft)
Orifice Area (sq. inches)
User Input: Vertical Orifice (Circular or Rectangular)Calculated Parameters for Vertical Orifice
Zone 2 Circular Not Selected Zone 2 Circular Not Selected
Invert of Vertical Orifice = 1.44 N/A ft (relative to basin bottom at Stage = 0 ft) Vertical Orifice Area = N/A
Depth at top of Zone using Vertical Orifice = 2.57 N/A ft (relative to basin bottom at Stage = 0 ft) Vertical Orifice Centroid = N/A
Vertical Orifice Diameter = N/A inches
User Input: Overflow Weir (Dropbox with Flat or Sloped Grate and Outlet Pipe OR Rectangular/Trapezoidal Weir (and No Outlet Pipe) Calculated Parameters for Overflow Weir
grate Zone 3 Weir Not Selected Zone 3 Weir Not Selected
Overflow Weir Front Edge Height, Ho = 2.54 N/A ft (relative to basin bottom at Stage = 0 ft)Height of Grate Upper Edge, Ht =3.79 N/A
Overflow Weir Front Edge Length = 5.00 N/A feet Overflow Weir Slope Length = 5.15 N/A
Overflow Weir Grate Slope = 4.00 N/A H:V Grate Open Area / 100-yr Orifice Area = 39.13 N/A
Horiz. Length of Weir Sides = 5.00 N/A feet Overflow Grate Open Area w/o Debris = 17.94 N/A
Overflow Grate Type = Type C Grate N/A Overflow Grate Open Area w/ Debris = 8.97 N/A
Debris Clogging % = 50% N/A %
User Input: Outlet Pipe w/ Flow Restriction Plate (Circular Orifice, Restrictor Plate, or Rectangular Orifice)Calculated Parameters for Outlet Pipe w/ Flow Restriction Plate
Zone 3 Restrictor Not Selected Zone 3 Restrictor Not Selected
Depth to Invert of Outlet Pipe = 0.00 N/A ft (distance below basin bottom at Stage = 0 ft)Outlet Orifice Area = 0.46 N/A
Outlet Pipe Diameter = 15.00 N/A inches Outlet Orifice Centroid = 0.29 N/A
Restrictor Plate Height Above Pipe Invert = 6.00 inches Half-Central Angle of Restrictor Plate on Pipe = 1.37 N/A
User Input: Emergency Spillway (Rectangular or Trapezoidal)Calculated Parameters for Spillway
Spillway Invert Stage= ft (relative to basin bottom at Stage = 0 ft) Spillway Design Flow Depth= feet
Spillway Crest Length = feet Stage at Top of Freeboard = feet
Spillway End Slopes = H:V Basin Area at Top of Freeboard = acres
Freeboard above Max Water Surface = feet Basin Volume at Top of Freeboard = acre-ft
Max Ponding Depth of Target Storage Volume =4.75 feet Discharge at Top of Freeboard = cfs
Routed Hydrograph Results
Design Storm Return Period =WQCV EURV 2 Year 5 Year 10 Year 25 Year 50 Year 100 Year
One-Hour Rainfall Depth (in) =N/A N/A 0.82 1.13 1.40 1.93 2.40 2.86
CUHP Runoff Volume (acre-ft) =0.215 0.632 0.404 0.623 0.849 1.353 1.787 2.238
Inflow Hydrograph Volume (acre-ft) =N/A N/A 0.404 0.623 0.849 1.353 1.787 2.238
CUHP Predevelopment Peak Q (cfs) =N/A N/A 0.1 1.3 3.4 9.2 13.6 18.4
OPTIONAL Override Predevelopment Peak Q (cfs) =N/A N/A 2.2
Predevelopment Unit Peak Flow, q (cfs/acre) =N/A N/A 0.01 0.12 0.31 0.85 1.26 0.20
Peak Inflow Q (cfs) =N/A N/A 6.7 10.4 14.1 23.1 30.4 38.4
Peak Outflow Q (cfs) =0.1 0.2 0.2 0.2 1.0 3.9 4.3 4.7
Ratio Peak Outflow to Predevelopment Q =N/A N/A N/A 0.2 0.3 0.4 0.3 2.2
Structure Controlling Flow =Plate Overflow Weir 1 Plate Plate Overflow Weir 1 Outlet Plate 1 Outlet Plate 1 Outlet Plate 1
Max Velocity through Grate 1 (fps) =N/A N/A N/A N/A 0.0 0.2 0.2 0.2
Max Velocity through Grate 2 (fps) =N/A N/A N/A N/A N/A N/A N/A N/A
Time to Drain 97% of Inflow Volume (hours) =37 56 47 56 60 56 54 53
Time to Drain 99% of Inflow Volume (hours) =40 63 52 63 67 65 64 64
Maximum Ponding Depth (ft) =1.40 2.54 1.88 2.43 2.83 3.40 4.02 4.75
Area at Maximum Ponding Depth (acres) =0.29 0.43 0.36 0.41 0.45 0.50 0.54 0.57
Maximum Volume Stored (acre-ft) =0.217 0.635 0.371 0.585 0.762 1.032 1.353 1.753
The user can override the default CUHP hydrographs and runoff volumes by entering new values in the Inflow Hydrographs table (Columns W through AF).
DETENTION BASIN OUTLET STRUCTURE DESIGN
MHFD-Detention, Version 4.04 (February 2021)
Fairway Lane Apartments
SE POND
Example Zone Configuration (Retention Pond)
MHFD-Detention_v4 04 (3).xlsm, Outlet Structure 1/6/2022, 10:39 AM
COUNTA for Basin Tab = 1 Ao Dia WQ Plate Type Vert Orifice 1Vert Orifice 2
Count_Underdrain = 0 0.11(diameter = 3/8 inch)2 2 1
Count_WQPlate = 1 0.14(diameter = 7/16 inch)
Count_VertOrifice1 = 0 0.18(diameter = 1/2 inch)Outlet Plate 1 Outlet Plate 2 Drain Time Message Boolean
Count_VertOrifice2 = 0 0.24(diameter = 9/16 inch)4 1 5yr, <72hr 0
Count_Weir1 = 1 0.29(diameter = 5/8 inch)>5yr, <120hr 0
Count_Weir2 = 0 0.36(diameter = 11/16 inch)Max Depth Row
Count_OutletPipe1 = 1 0.42(diameter = 3/4 inch)WQCV 141 Watershed Constraint Check
Count_OutletPipe2 = 0 0.50(diameter = 13/16 inch)2 Year 189 Slope 0.025
COUNTA_2 (Standard FSD Setup)= 1 0.58(diameter = 7/8 inch)EURV 255 Shape 2.50
Hidden Parameters & Calculations 0.67(diameter = 15/16 inch)5 Year 244
MaxPondDepth_Error? FALSE 0.76 (diameter = 1 inch)10 Year 284 Spillway Depth
Cd_Broad-Crested Weir 3.00 0.86(diameter = 1-1/16 inches)25 Year 341
WQ Plate Flow at 100yr depth = 0.35 0.97(diameter = 1-1/8 inches)50 Year 403
CLOG #1= 50% 1.08(diameter = 1-3/16 inches)100 Year 476 1 Z1_Boolean
n*Cdw #1 = 0.32 1.20(diameter = 1-1/4 inches)500 Year 676 0 Z2_Boolean
n*Cdo #1 = 1.45 1.32(diameter = 1-5/16 inches)Zone3_Pulldown Message 1 Z3_Boolean
Overflow Weir #1 Angle = 0.245 1.45(diameter = 1-3/8 inches)1 Opening Message
CLOG #2= N/A 1.59(diameter = 1-7/16 inches)Draintime Running
n*Cdw #2 = N/A 1.73(diameter = 1-1/2 inches)Outlet Boolean Outlet Rank Total (1 to 4)
n*Cdo #2 = N/A 1.88(diameter = 1-9/16 inches)Vertical Orifice 1 0 0
1
Overflow Weir #2 Angle = N/A 2.03(diameter = 1-5/8 inches)Vertical Orifice 2 0 0 Boolean
Underdrain Q at 100yr depth = 0.00 2.20(diameter = 1-11/16 inches)Overflow Weir 1 1 1 0 Max Depth
VertOrifice1 Q at 100yr depth = 0.00 2.36(diameter = 1-3/4 inches)Overflow Weir 2 0 0 0 500yr Depth
VertOrifice2 Q at 100yr depth = 0.00 2.54(diameter = 1-13/16 inches)Outlet Pipe 1 1 1 0 Freeboard
2.72(diameter = 1-7/8 inches)Outlet Pipe 2 0 0 0 Spillway
Count_User_Hydrographs 0 2.90(diameter = 1-15/16 inches)0 Spillway Length
CountA_3 (EURV & 100yr) = 1 3.09(diameter = 2 inches)FALSE Time Interval
CountA_4 (100yr Only) = 1 3.29(use rectangular openings)Button Visibility Boolean
COUNTA_5 (FSD Weir Only)= 0 0 WQCV Underdrain
COUNTA_6 (EURV Weir Only)= 1 1 WQCV Plate
0 EURV-WQCV Plate
Outlet1_Pulldown_Boolean 1 EURV-WQCV VertOriice
Outlet2_Pulldown_Boolean 1 Outlet 90% Qpeak
Outlet3_Pulldown_Boolean 0 Outlet Undetained
0 Weir Only 90% Qpeak
0 Five Year Ratio Plate
0 Five Year Ratio VertOrifice
EURV_draintime_user
Spillway Options
Offset
Overlapping
S-A-V-D Chart Axis Default X-axis Left Y-Axis Right Y-Axis
minimum bound 0.00 0 0
maximum bound 8.00 130,000 10
S-A-V-D Chart Axis Override X-axis Left Y-Axis Right Y-Axis
minimum bound
maximum bound
MHFD-Detention, Version 4.04 (February 2021)
DETENTION BASIN OUTLET STRUCTURE DESIGN
0
10
20
30
40
50
60
70
0.1 1 10FLOW [cfs]TIME [hr]
500YR IN
500YR OUT
100YR IN
100YR OUT
50YR IN
50YR OUT
25YR IN
25YR OUT
10YR IN
10YR OUT
5YR IN
5YR OUT
2YR IN
2YR OUT
EURV IN
EURV OUT
WQCV IN
WQCV OUT
0
1
2
3
4
5
6
7
8
0.1 1 10 100PONDING DEPTH [ft]DRAIN TIME [hr]
500YR
100YR
50YR
25YR
10YR
5YR
2YR
EURV
WQCV
0
1
2
3
4
5
6
7
8
9
10
0
20,000
40,000
60,000
80,000
100,000
120,000
0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 OUTFLOW [cfs]AREA [ft^2], VOLUME [ft^3]PONDING DEPTH [ft]
User Area [ft^2]
Interpolated Area [ft^2]
Summary Area [ft^2]
Volume [ft^3]
Summary Volume [ft^3]
Outflow [cfs]
Summary Outflow [cfs]
MHFD-Detention_v4 04 (3).xlsm, Outlet Structure 1/6/2022, 10:39 AM
Outflow Hydrograph Workbook Filename:
Inflow Hydrographs
The user can override the calculated inflow hydrographs from this workbook with inflow hydrographs developed in a separate program.
SOURCE CUHP CUHP CUHP CUHP CUHP CUHP CUHP CUHP CUHP
Time Interval TIME WQCV [cfs] EURV [cfs] 2 Year [cfs] 5 Year [cfs] 10 Year [cfs] 25 Year [cfs] 50 Year [cfs] 100 Year [cfs] 500 Year [cfs]
5.00 min 0:00:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0:05:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
0:10:00 0.00 0.00 0.00 0.00 0.00 0.00 0.26 0.25 1.39
0:15:00 0.00 0.00 0.31 1.07 1.62 1.53 2.27 2.46 4.67
0:20:00 0.00 0.00 2.47 3.80 4.87 3.86 5.08 5.97 11.66
0:25:00 0.00 0.00 5.53 8.64 12.18 8.80 12.52 15.13 28.49
0:30:00 0.00 0.00 6.67 10.41 14.12 21.15 28.21 33.93 57.53
0:35:00 0.00 0.00 6.06 9.38 12.57 23.15 30.36 38.37 63.84
0:40:00 0.00 0.00 5.33 8.04 10.76 21.77 28.40 35.67 59.09
0:45:00 0.00 0.00 4.40 6.76 9.16 18.90 24.64 31.91 52.73
0:50:00 0.00 0.00 3.65 5.73 7.58 16.63 21.62 27.81 45.89
0:55:00 0.00 0.00 3.15 4.88 6.53 13.62 17.76 23.52 38.91
1:00:00 0.00 0.00 2.80 4.29 5.81 11.58 15.15 20.65 34.23
1:05:00 0.00 0.00 2.49 3.79 5.18 10.08 13.22 18.56 30.78
1:10:00 0.00 0.00 2.07 3.31 4.57 8.34 10.98 14.92 24.88
1:15:00 0.00 0.00 1.69 2.76 4.03 6.82 9.02 11.83 19.85
1:20:00 0.00 0.00 1.42 2.30 3.40 5.26 6.96 8.66 14.68
1:25:00 0.00 0.00 1.27 2.04 2.86 4.12 5.47 6.34 10.96
1:30:00 0.00 0.00 1.19 1.90 2.52 3.30 4.39 4.92 8.67
1:35:00 0.00 0.00 1.15 1.81 2.29 2.77 3.69 4.05 7.26
1:40:00 0.00 0.00 1.13 1.61 2.12 2.42 3.22 3.45 6.27
1:45:00 0.00 0.00 1.11 1.47 2.00 2.19 2.91 3.05 5.62
1:50:00 0.00 0.00 1.09 1.36 1.92 2.04 2.70 2.76 5.15
1:55:00 0.00 0.00 0.95 1.28 1.81 1.93 2.55 2.56 4.83
2:00:00 0.00 0.00 0.83 1.18 1.63 1.86 2.45 2.46 4.66
2:05:00 0.00 0.00 0.61 0.87 1.18 1.35 1.78 1.79 3.39
2:10:00 0.00 0.00 0.44 0.62 0.84 0.96 1.27 1.28 2.43
2:15:00 0.00 0.00 0.31 0.44 0.59 0.68 0.90 0.92 1.73
2:20:00 0.00 0.00 0.22 0.30 0.41 0.48 0.63 0.64 1.21
2:25:00 0.00 0.00 0.15 0.20 0.28 0.33 0.43 0.44 0.82
2:30:00 0.00 0.00 0.10 0.14 0.19 0.22 0.29 0.30 0.57
2:35:00 0.00 0.00 0.06 0.09 0.12 0.15 0.19 0.19 0.37
2:40:00 0.00 0.00 0.03 0.05 0.07 0.08 0.11 0.11 0.21
2:45:00 0.00 0.00 0.01 0.02 0.03 0.04 0.05 0.05 0.09
2:50:00 0.00 0.00 0.00 0.01 0.01 0.01 0.01 0.01 0.03
2:55:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3:00:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3:05:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3:10:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3:15:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3:20:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3:25:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3:30:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3:35:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3:40:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3:45:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3:50:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
3:55:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4:00:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4:05:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4:10:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4:15:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4:20:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4:25:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4:30:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4:35:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4:40:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4:45:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4:50:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
4:55:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5:00:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5:05:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5:10:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5:15:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5:20:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5:25:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5:30:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5:35:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5:40:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5:45:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5:50:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
5:55:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
6:00:00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
DETENTION BASIN OUTLET STRUCTURE DESIGN
MHFD-Detention_v4 04 (3).xlsm, Outlet Structure 1/6/2022, 10:39 AM
Weir Report
Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc.Tuesday, Oct 26 2021
Detention Pond Spillway
Trapezoidal Weir
Crest = Sharp
Bottom Length (ft) = 30.00
Total Depth (ft) = 1.00
Side Slope (z:1) = 4.00
Calculations
Weir Coeff. Cw = 3.10
Compute by: Known Q
Known Q (cfs) = 88.57
Highlighted
Depth (ft) = 0.92
Q (cfs) = 88.57
Area (sqft) = 30.99
Velocity (ft/s) = 2.86
Top Width (ft) = 37.36
0 5 10 15 20 25 30 35 40 45 50
Depth (ft)Depth (ft)Detention Pond Spillway
-0.50 -0.50
0.00 0.00
0.50 0.50
1.00 1.00
1.50 1.50
2.00 2.00
Length (ft)Weir W.S.
APPENDIX E Fairway Lane Apartments – Fort Collins, CO
20065
North System (S1 East and West Combined)
Total Contributory Area: 124,910 sf
- East: 79,855 sf
- West: 45,055 sf
Total Contributory New and/or Modified Impervious Area: 91,874 sf
- East: 58,735 sf
- West: 33,139 sf
Total WQCV Required / Provided: 2,951 cu-ft / 3,007 cu-ft
- East: 1,887 cu-ft / 1,888 cu-ft
- West: 1,064 cu-ft / 1,119 cu-ft
Site Information
Total New and/or Modified Impervious Area: 286,910 sf
75% of Total New and/or Modified Impervious Area: 215,183 sf
Total New and/or Modified Impervious Treated: 217,720 sf
Total Percent of New and/or Modified Impervious Area Treated: 75.9%
South System (S2)
Total Contributory Area: 175,679 sf
Total Contributory New and/or Modified Impervious Area:
124,846 sf
WQCV Required / Provided: 4,042cu-ft / 4,264 cu-ft
108,467 sf
42,518 sf
Proposed South System
(S2) = 54 Chambers
Proposed North System
(S1- East) = 26 Chambers
Purple area contributory to
south (S2) Stormtech
system
Green area contributory to north
(S1-East) Stormtech system
Proposed North System
(S1- West) = 15 Chambers
Blue area contributory to north
(S1-West) Stormtech system
NORTHWEST SYSTEM
SOUTHERN SYSTEM
NORTHEAST SYSTEM
©2021 ADS, INC.
PROJECT INFORMATION
ADS SALES REP:
ENGINEERED
PRODUCT
MANAGER:
PROJECT NO:
FAIRWAY LANE APARTMENTS
FORT COLLINS, CO
MARK KAELBERER
720-256-8225
MARK.KAELBERER@ADS-PIPE.COM
S247917
Advanced Drainage Systems, Inc.
JEROME MAGSINO
303-349-7555
JEROME.MAGSINO@ADS-PIPE.COM
IMPORTANT - NOTES FOR THE BIDDING AND INSTALLATION OF THE SC-740 SYSTEM
1.STORMTECH SC-740 CHAMBERS SHALL NOT BE INSTALLED UNTIL THE MANUFACTURER'S REPRESENTATIVE HAS COMPLETED A
PRE-CONSTRUCTION MEETING WITH THE INSTALLERS.
2.STORMTECH SC-740 CHAMBERS SHALL BE INSTALLED IN ACCORDANCE WITH THE "STORMTECH SC-310/SC-740/DC-780 CONSTRUCTION GUIDE".
3.CHAMBERS ARE NOT TO BE BACKFILLED WITH A DOZER OR AN EXCAVATOR SITUATED OVER THE CHAMBERS.
STORMTECH RECOMMENDS 3 BACKFILL METHODS:
·STONESHOOTER LOCATED OFF THE CHAMBER BED.
·BACKFILL AS ROWS ARE BUILT USING AN EXCAVATOR ON THE FOUNDATION STONE OR SUBGRADE.
·BACKFILL FROM OUTSIDE THE EXCAVATION USING A LONG BOOM HOE OR EXCAVATOR.
4.THE FOUNDATION STONE SHALL BE LEVELED AND COMPACTED PRIOR TO PLACING CHAMBERS.
5.JOINTS BETWEEN CHAMBERS SHALL BE PROPERLY SEATED PRIOR TO PLACING STONE.
6.MAINTAIN MINIMUM - 6" (150 mm) SPACING BETWEEN THE CHAMBER ROWS.
7.EMBEDMENT STONE SURROUNDING CHAMBERS MUST BE A CLEAN, CRUSHED, ANGULAR STONE 3/4-2" (20-50 mm).
8.THE CONTRACTOR MUST REPORT ANY DISCREPANCIES WITH CHAMBER FOUNDATION MATERIALS BEARING CAPACITIES TO THE SITE DESIGN
ENGINEER.
9.ADS RECOMMENDS THE USE OF "FLEXSTORM CATCH IT" INSERTS DURING CONSTRUCTION FOR ALL INLETS TO PROTECT THE SUBSURFACE
STORMWATER MANAGEMENT SYSTEM FROM CONSTRUCTION SITE RUNOFF.
NOTES FOR CONSTRUCTION EQUIPMENT
1.STORMTECH SC-740 CHAMBERS SHALL BE INSTALLED IN ACCORDANCE WITH THE "STORMTECH SC-310/SC-740/DC-780 CONSTRUCTION GUIDE".
2.THE USE OF CONSTRUCTION EQUIPMENT OVER SC-740 CHAMBERS IS LIMITED:
·NO EQUIPMENT IS ALLOWED ON BARE CHAMBERS.
·NO RUBBER TIRED LOADERS, DUMP TRUCKS, OR EXCAVATORS ARE ALLOWED UNTIL PROPER FILL DEPTHS ARE REACHED IN ACCORDANCE
WITH THE "STORMTECH SC-310/SC-740/DC-780 CONSTRUCTION GUIDE".
·WEIGHT LIMITS FOR CONSTRUCTION EQUIPMENT CAN BE FOUND IN THE "STORMTECH SC-310/SC-740/DC-780 CONSTRUCTION GUIDE".
3.FULL 36" (900 mm) OF STABILIZED COVER MATERIALS OVER THE CHAMBERS IS REQUIRED FOR DUMP TRUCK TRAVEL OR DUMPING.
USE OF A DOZER TO PUSH EMBEDMENT STONE BETWEEN THE ROWS OF CHAMBERS MAY CAUSE DAMAGE TO THE CHAMBERS AND IS NOT AN
ACCEPTABLE BACKFILL METHOD. ANY CHAMBERS DAMAGED BY THE "DUMP AND PUSH" METHOD ARE NOT COVERED UNDER THE STORMTECH
STANDARD WARRANTY.
CONTACT STORMTECH AT 1-888-892-2694 WITH ANY QUESTIONS ON INSTALLATION REQUIREMENTS OR WEIGHT LIMITS FOR CONSTRUCTION EQUIPMENT.
SC-740 STORMTECH CHAMBER SPECIFICATIONS
1.CHAMBERS SHALL BE STORMTECH SC-740.
2.CHAMBERS SHALL BE ARCH-SHAPED AND SHALL BE MANUFACTURED FROM VIRGIN, IMPACT-MODIFIED POLYPROPYLENE
COPOLYMERS.
3.CHAMBERS SHALL MEET THE REQUIREMENTS OF ASTM F2418-16a, "STANDARD SPECIFICATION FOR POLYPROPYLENE (PP)
CORRUGATED WALL STORMWATER COLLECTION CHAMBERS".
4.CHAMBER ROWS SHALL PROVIDE CONTINUOUS, UNOBSTRUCTED INTERNAL SPACE WITH NO INTERNAL SUPPORTS THAT WOULD
IMPEDE FLOW OR LIMIT ACCESS FOR INSPECTION.
5.THE STRUCTURAL DESIGN OF THE CHAMBERS, THE STRUCTURAL BACKFILL, AND THE INSTALLATION REQUIREMENTS SHALL ENSURE
THAT THE LOAD FACTORS SPECIFIED IN THE AASHTO LRFD BRIDGE DESIGN SPECIFICATIONS, SECTION 12.12, ARE MET FOR: 1)
LONG-DURATION DEAD LOADS AND 2) SHORT-DURATION LIVE LOADS, BASED ON THE AASHTO DESIGN TRUCK WITH CONSIDERATION
FOR IMPACT AND MULTIPLE VEHICLE PRESENCES.
6.CHAMBERS SHALL BE DESIGNED, TESTED AND ALLOWABLE LOAD CONFIGURATIONS DETERMINED IN ACCORDANCE WITH ASTM F2787,
"STANDARD PRACTICE FOR STRUCTURAL DESIGN OF THERMOPLASTIC CORRUGATED WALL STORMWATER COLLECTION CHAMBERS".
LOAD CONFIGURATIONS SHALL INCLUDE: 1) INSTANTANEOUS (<1 MIN) AASHTO DESIGN TRUCK LIVE LOAD ON MINIMUM COVER 2)
MAXIMUM PERMANENT (75-YR) COVER LOAD AND 3) ALLOWABLE COVER WITH PARKED (1-WEEK) AASHTO DESIGN TRUCK.
7.REQUIREMENTS FOR HANDLING AND INSTALLATION:
·TO MAINTAIN THE WIDTH OF CHAMBERS DURING SHIPPING AND HANDLING, CHAMBERS SHALL HAVE INTEGRAL, INTERLOCKING
STACKING LUGS.
·TO ENSURE A SECURE JOINT DURING INSTALLATION AND BACKFILL, THE HEIGHT OF THE CHAMBER JOINT SHALL NOT BE LESS
THAN 2”.
·TO ENSURE THE INTEGRITY OF THE ARCH SHAPE DURING INSTALLATION, a) THE ARCH STIFFNESS CONSTANT SHALL BE
GREATER THAN OR EQUAL TO 550 LBS/IN/IN. THE ASC IS DEFINED IN SECTION 6.2.8 OF ASTM F2418. AND b) TO RESIST CHAMBER
DEFORMATION DURING INSTALLATION AT ELEVATED TEMPERATURES (ABOVE 73° F / 23° C), CHAMBERS SHALL BE PRODUCED
FROM REFLECTIVE GOLD OR YELLOW COLORS.
8.ONLY CHAMBERS THAT ARE APPROVED BY THE SITE DESIGN ENGINEER WILL BE ALLOWED. UPON REQUEST BY THE SITE DESIGN
ENGINEER OR OWNER, THE CHAMBER MANUFACTURER SHALL SUBMIT A STRUCTURAL EVALUATION FOR APPROVAL BEFORE
DELIVERING CHAMBERS TO THE PROJECT SITE AS FOLLOWS:
·THE STRUCTURAL EVALUATION SHALL BE SEALED BY A REGISTERED PROFESSIONAL ENGINEER.
·THE STRUCTURAL EVALUATION SHALL DEMONSTRATE THAT THE SAFETY FACTORS ARE GREATER THAN OR EQUAL TO 1.95 FOR
DEAD LOAD AND 1.75 FOR LIVE LOAD, THE MINIMUM REQUIRED BY ASTM F2787 AND BY SECTIONS 3 AND 12.12 OF THE AASHTO
LRFD BRIDGE DESIGN SPECIFICATIONS FOR THERMOPLASTIC PIPE.
·THE TEST DERIVED CREEP MODULUS AS SPECIFIED IN ASTM F2418 SHALL BE USED FOR PERMANENT DEAD LOAD DESIGN
EXCEPT THAT IT SHALL BE THE 75-YEAR MODULUS USED FOR DESIGN.
9.CHAMBERS AND END CAPS SHALL BE PRODUCED AT AN ISO 9001 CERTIFIED MANUFACTURING FACILITY.
FOR STORMTECH
INSTRUCTIONS,
DOWNLOAD THE
INSTALLATION APP
SiteASSIST
SHEET
OFDATE:PROJECT #:DRAWN:CHECKED:THIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.4640 TRUEMAN BLVDHILLIARD, OH 430262 807/21/21S247917GGCJPR FAIRWAY LANE APARTMENTSFORT COLLINS, CODATEDRWNCHKDDESCRIPTION 12/10/21GDLGGCREVISED PER ENGINEER12-14-21MJKCTSREVISE PER COMMENTS01-12-22TSG- - -REVISED PER ENGINEER'S MARK UP0010'20'StormTechChamber System888-892-2694 | WWW.STORMTECH.COM®NOTES
·MANIFOLD SIZE TO BE DETERMINED BY SITE DESIGN ENGINEER. SEE TECHNICAL NOTE 6.32 FOR MANIFOLD SIZING GUIDANCE.
·DUE TO THE ADAPTATION OF THIS CHAMBER SYSTEM TO SPECIFIC SITE AND DESIGN CONSTRAINTS, IT MAY BE NECESSARY TO CUT AND COUPLE ADDITIONAL PIPE TO
STANDARD MANIFOLD COMPONENTS IN THE FIELD.
·THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET.
·THIS CHAMBER SYSTEM WAS DESIGNED WITHOUT SITE-SPECIFIC INFORMATION ON SOIL CONDITIONS OR BEARING CAPACITY. THE SITE DESIGN ENGINEER IS
RESPONSIBLE FOR DETERMINING THE SUITABILITY OF THE SOIL AND PROVIDING THE BEARING CAPACITY OF THE INSITU SOILS. THE BASE STONE DEPTH MAY BE
INCREASED OR DECREASED ONCE THIS INFORMATION IS PROVIDED.
·THE SITE DESIGN ENGINEER MUST REVIEW THE PROXIMITY OF THE CHAMBERS TO THE BUILDING/STRUCTURE. NO FOUNDATION LOADS SHALL BE TRANSMITTED TO THE
CHAMBERS. THE SITE DESIGN ENGINEER MUST CONSIDER EFFECTS OF POSSIBLE SATURATED SOILS ON BEARING CAPACITY OF SOILS AND SEEPAGE INTO BASEMENTS.
·ADS DOES NOT DESIGN OR PROVIDE MEMBRANE LINER SYSTEMS FOR CISTERNS. TO MINIMIZE THE LEAKAGE POTENTIAL OF LINER SYSTEMS, THE MEMBRANE LINER
SYSTEM SHOULD BE DESIGNED BY A KNOWLEDGEABLE GEOTEXTILE PROFESSIONAL AND INSTALLED BY A QUALIFIED CONTRACTOR.
·NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE
ACHIEVED ON SITE.
24" X 24" ADS N-12 BOTTOM MANIFOLD
INVERT 0.1" ABOVE CHAMBER BASE
(SEE NOTES)
6" ADS N-12 DUAL WALL PERFORATED HDPE UNDERDRAIN
(SIZE TBD BY ENGINEER / SOLID OUTSIDE PERIMETER STONE)
INSPECTION PORT
(TYP 3 PLACES)
STRUCTURE PER PLAN
SHOWN AS 30" NYLOPLAST BASIN
(24" SUMP MIN)
ISOLATOR ROW PLUS
(SEE DETAIL / TYP 3 PLACES)
24" PREFABRICATED END CAP, PART# SC740EPE24B
TYP OF ALL SC-740 24" CONNECTIONS
CONCEPTUAL LAYOUT - NORTHWEST SYSTEM
15 STORMTECH SC-740 CHAMBERS
6 STORMTECH SC-740 END CAPS
6 STONE ABOVE (in)
6 STONE BELOW (in)
40 % STONE VOID
1,522 INSTALLED SYSTEM VOLUME (CF) (PERIMETER STONE INCLUDED)
792 SYSTEM AREA (ft²)
130 SYSTEM PERIMETER (ft)
CONCEPTUAL ELEVATIONS - NORTHWEST SYSTEM
5013.39 MAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED)
5007.39 MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC)
5006.89 MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC)
5006.89 MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT)
5006.89 MINIMUM ALLOWABLE GRADE (TOP OF RIGID PAVEMENT)
5005.89 TOP OF STONE
5005.39 TOP OF SC-740 CHAMBER
5002.90 24" ISOLATOR ROW PLUS MANIFOLD / CONNECTION INVERT
5002.89 BOTTOM OF SC-740 CHAMBER
5002.39 UNDERDRAIN INVERT
5002.39 BOTTOM OF STONE
24" PREFABRICATED END CAP, PART# SC740EPE24BR
TYP OF ALL SC-740 24" ISOLATOR ROW PLUS CONNECTIONS
THERMOPLASTIC LINER
(SEE TECHNICAL NOTE 6.50 / PROVIDED BY OTHERS / DESIGN BY OTHERS)
OUTLET STRUCTURE PER PLAN
SHOWN AS 30" NYLOPLAST BASIN
(DESIGN BY ENGINEER)
24" X 24" ADS N-12 BOTTOM MANIFOLD
INVERT 0.1" ABOVE CHAMBER BASE
(SEE NOTES)
PROPOSED 30" NYLOPLAST BASIN
(FOR ISOLATOR ROW ACCESS/24" MIN SUMP)
24" X 24" ADS N-12 BOTTOM MANIFOLD
INVERT 0.1" ABOVE CHAMBER BASE
(SEE NOTES)
24" ADS N-12 BOTTOM CONNECTION
INVERT 0.1" ABOVE CHAMBER BASE
(SEE NOTES)
24" ADS N-12 BOTTOM CONNECTION
INVERT 0.1" ABOVE CHAMBER BASE
(SEE NOTES)16.35'13.75'48.43'
37.19'
Project:
Chamber Model - SC-740
Units -Imperial
Number of chambers - 15
Voids in the stone (porosity) - 40 %
Base of Stone Elevation - 5002.39 ft
Amount of Stone Above Chambers - 6 in
Amount of Stone Below Chambers - 6 in
6
Area of system -792 sf Min. Area -
Height of
System
Incremental Single
Chamber
Incremental Total
Chamber
Incremental
Stone
Incremental Ch
& St
Cumulative
Chamber Elevation 1
(inches) (cubic feet) (cubic feet) (cubic feet) (cubic feet)(cubic feet) (feet)
42 0.00 0.00 26.40 26.40 1522.36 5005.89
41 0.00 0.00 26.40 26.40 1495.96 5005.81
40 0.00 0.00 26.40 26.40 1469.56 5005.72 0cf above elevation
39 0.00 0.00 26.40 26.40 1443.16 5005.64 0cf below elevation
38 0.00 0.00 26.40 26.40 1416.76 5005.56 1522.36cf above elevation 674.8
37 0.00 0.00 26.40 26.40 1390.36 5005.47 0cf below elevation 674.8
36 0.05 0.82 26.07 26.89 1363.96 5005.39 1522.36cf between elevations 674.8 and
35 0.16 2.44 25.42 27.87 1337.06 5005.31
34 0.28 4.23 24.71 28.94 1309.20 5005.22
33 0.60 9.06 22.78 31.84 1280.26 5005.14 WQ Volume: cf
32 0.80 12.03 21.59 33.62 1248.42 5005.06 0cf below elevation
31 0.95 14.26 20.70 34.96 1214.81 5004.97
30 1.07 16.12 19.95 36.07 1179.85 5004.89
29 1.18 17.71 19.32 37.02 1143.78 5004.81 WQv achieved at elevation:
28 1.27 18.98 18.81 37.79 1106.76 5004.72
27 1.36 20.33 18.27 38.60 1068.97 5004.64
26 1.45 21.81 17.68 39.49 1030.37 5004.56
25 1.52 22.87 17.25 40.12 990.88 5004.47
24 1.58 23.73 16.91 40.64 950.76 5004.39
23 1.64 24.63 16.55 41.18 910.12 5004.31
22 1.70 25.49 16.20 41.70 868.94 5004.22
21 1.75 26.29 15.88 42.18 827.24 5004.14
20 1.80 27.04 15.58 42.63 785.07 5004.06
19 1.85 27.82 15.27 43.09 742.44 5003.97
18 1.89 28.40 15.04 43.44 699.35 5003.89
17 1.93 29.01 14.80 43.81 655.91 5003.81
16 1.97 29.62 14.55 44.17 612.10 5003.72
15 2.01 30.15 14.34 44.49 567.93 5003.64
14 2.04 30.67 14.13 44.80 523.44 5003.56
13 2.07 31.12 13.95 45.07 478.63 5003.47
12 2.10 31.57 13.77 45.34 433.56 5003.39
11 2.13 31.98 13.61 45.59 388.22 5003.31
10 2.15 32.31 13.48 45.78 342.63 5003.22
9 2.18 32.66 13.34 45.99 296.84 5003.14
8 2.20 32.98 13.21 46.19 250.85 5003.06
7 2.21 33.11 13.16 46.27 204.67 5002.97
6 0.00 0.00 26.40 26.40 158.40 5002.89
5 0.00 0.00 26.40 26.40 132.00 5002.81
4 0.00 0.00 26.40 26.40 105.60 5002.72
3 0.00 0.00 26.40 26.40 79.20 5002.64
2 0.00 0.00 26.40 26.40 52.80 5002.56
1 0.00 0.00 26.40 26.40 26.40 5002.47
StormTech SC-740 Cumulative Storage Volumes
REV3 - FAIRWAY - N.WEST - S247917
507 sf min. area
Include Perimeter Stone in Calculations
Click Here for Metric
Max WQ Elev = 5004.75
(Equal to Inv Out South in
Storm Structure B3)
Provides 1,119 cf of WQCV
36" is top of
chambers
Fairway Lane Apartments S1 Stormtech System (West)
Water Quality Capture Volume (WQCV) Calculations
Total Area of New and/or Modified Impervious Area Contributory to Stormtech = 33,139 sq-ft
a=0.8 12-Hour Drain Time
I=90%
WQCV=0.321 Watershed-Inches
A=0.761 Acres
V=0.024 Acre-Feet
Therefore;1,064 cubic-feet of WQCV is required to be treated
=12 x 1.2
= (0.91 −1.19 +0.78
Fairway Lane ApartmentsFort Collins, COVault IDIn-Flow, WQ(cfs)Chamber TypeMimimum No. ofChambersdMinimum ReleaseRatee (cfs)Required Chamber Volume by FAA Method (cf)Mimimum No. ofChambersfProvided Number of ChambersProvided Release Ratee (cfs)Provided Chamber Volumeg(cf)Total Installed Chamber Volumeh(cf)S1 (West) 0.98 SC-74015 0.35 264 4 15 0.35 689 1124Note: "Chamber Volume" refers to the open volume within the vaults. "Installed Chamber Volume" refers to the total volume provided, including the surrounding aggregates.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.In-Flow WQd. Number of chambers required to provide full WQCV within total installed system, including aggregate.C0.9e. Release rate per chamber times number of chambers.i1.43in/hrf. Number of chambers required to provide required FAA storage volume stored within the chamber only (no aggregate storage).A0.76acresg. Volume provided in chambers only (no aggregate storage). This number must meet or exceed the required FAA storage volume.h. System volume includes total number of chambers, plus surrounding aggregate. This number must meet or exceed the required WQCV.SC-160 SC-310MC-350025.0 34.07784.4 85.48612.0 16.04514.7 20.243.26.9 14.7109.915.0 29.31750.35 gpm/sf7.48052 gal0.133681 cf0.002228 cfs*Flow rate based on 1/2 of Nov 07 QMAX in Figure 17 of UNH Testing ReportSC-160 SC-310MC-35000.011426 0.0157240.03368710640.024 45.90 74.90Chamber Configuration SummaryTotal Required WQ Volume (cf)Individual Chamber Release Ratea(cfs)Individual ChamberVolumeb (cf)Individual Installed Chamber Volumec (cf)30.2Chamber Volume (cf)StormTech Chamber DataChamber DimensionsSC-74045.9Chamber/Aggregate Volume (cf)74.9Chamber Flow Rate Conversion (gpm/sf to cfs)Flow Rate*1 cf =1 gallon =1 GPM =Width (in)51.0Length (in)85.4Height (in)30.0Floor Area (sf)Chamber Flow RateSC-740Flow Rate/chamber (cfs)0.023586Inverts at storm structure B3 set to accommodatethis flow in 8" pipe to chambers
S1 Stormtech System (West)
Chamber Product SC-740
Design Storm WQ Required Detention Volume
Developed "C" 0.9 Quantity Detention 264 (ft3)
Area 0.76 acres
Max Release Rate 0.35 cfs
Time Time
Ft.Collins WQ
Intensity
Q100 Inflow (Runoff) Volume Outflow (Release) Volume
Storage Detention
Volume
(mins) (secs) (in/hr) (cfs)(ft3) (ft
3) (ft
3)
5 300 1.43 1.0 293 105 188
10 600 1.11 0.8 456 210 246
15 900 0.94 0.6 579 315 264
20 1200 0.81 0.6 665 420 245
25 1500 0.72 0.5 739 525 214
30 1800 0.65 0.4 800 630 170
35 2100 0.59 0.4 847 735 112
40 2400 0.54 0.4 886 840 46
45 2700 0.50 0.3 923 945 -22
50 3000 0.46 0.3 944 1050 -106
55 3300 0.44 0.3 993 1155 -162
60 3600 0.41 0.3 1010 1260 -250
65 3900 0.39 0.3 1040 1365 -325
70 4200 0.37 0.3 1063 1470 -407
75 4500 0.35 0.2 1077 1575 -498
80 4800 0.33 0.2 1083 1680 -597
85 5100 0.32 0.2 1116 1785 -669
90 5400 0.31 0.2 1145 1890 -745
95 5700 0.29 0.2 1131 1995 -864
100 6000 0.28 0.2 1149 2100 -951
105 6300 0.27 0.2 1163 2205 -1042
110 6600 0.26 0.2 1174 2310 -1136
115 6900 0.3 0.2 1416 2415 -999
120 7200 0.25 0.2 1231 2520 -1289
SHEET
OFDATE:PROJECT #:DRAWN:CHECKED:THIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.4640 TRUEMAN BLVDHILLIARD, OH 430263 807/21/21S247917GGCJPR FAIRWAY LANE APARTMENTSFORT COLLINS, CODATEDRWNCHKDDESCRIPTION 12/10/21GDLGGCREVISED PER ENGINEER12-14-21MJKCTSREVISE PER COMMENTS01-12-22TSG- - -REVISED PER ENGINEER'S MARK UP0010'20'StormTechChamber System888-892-2694 | WWW.STORMTECH.COM®6" ADS N-12 DUAL WALL PERFORATED HDPE UNDERDRAIN
(SIZE TBD BY ENGINEER / SOLID OUTSIDE PERIMETER STONE)
INSPECTION PORT
(TYP 3 PLACES)
PROPOSED 30" NYLOPLAST BASIN
(24" SUMP MIN)
ISOLATOR ROW PLUS
(SEE DETAIL / TYP 3 PLACES)
24" PREFABRICATED END CAP, PART# SC740EPE24B
TYP OF ALL SC-740 24" CONNECTIONS
CONCEPTUAL LAYOUT - NORTHEAST SYSTEM
26 STORMTECH SC-740 CHAMBERS
6 STORMTECH SC-740 END CAPS
6 STONE ABOVE (in)
6 STONE BELOW (in)
40 % STONE VOID
2,344 INSTALLED SYSTEM VOLUME (CF) (PERIMETER STONE INCLUDED)
1,162 SYSTEM AREA (ft²)
185 SYSTEM PERIMETER (ft)
CONCEPTUAL ELEVATIONS - NORTHEAST SYSTEM
5011.72 MAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED)
5005.72 MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC)
5005.22 MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC)
5005.22 MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT)
5005.22 MINIMUM ALLOWABLE GRADE (TOP OF RIGID PAVEMENT)
5004.22 TOP OF STONE
5003.72 TOP OF SC-740 CHAMBER
5001.23 24" ISOLATOR ROW PLUS MANIFOLD / CONNECTION INVERT
5001.22 BOTTOM OF SC-740 CHAMBER
5000.72 UNDERDRAIN INVERT
5000.72 BOTTOM OF STONE
24" PREFABRICATED END CAP, PART# SC740EPE24BR
TYP OF ALL SC-740 24" ISOLATOR ROW PLUS CONNECTIONS
THERMOPLASTIC LINER
(SEE TECHNICAL NOTE 6.50 / PROVIDED BY OTHERS / DESIGN BY OTHERS)
OUTLET STRUCTURE PER PLAN
SHOWN AS 30" NYLOPLAST BASIN
(DESIGN BY ENGINEER)
24" X 24" ADS N-12 BOTTOM MANIFOLD
INVERT 0.1" ABOVE CHAMBER BASE
(SEE NOTES)
PROPOSED 30" NYLOPLAST BASIN
(FOR ISOLATOR ROW ACCESS /24" MIN SUMP)
24" X 24" ADS N-12 BOTTOM MANIFOLD
INVERT 0.1" ABOVE CHAMBER BASE
(SEE NOTES)
24" ADS N-12 BOTTOM CONNECTION
INVERT 0.1" ABOVE CHAMBER BASE
(SEE NOTES)15.75'13.75'24" ADS N-12 BOTTOM CONNECTION
INVERT 0.1" ABOVE CHAMBER BASE
(SEE NOTES)11.59'4.16'10.92'65.72'
76.64'
NOTES
·MANIFOLD SIZE TO BE DETERMINED BY SITE DESIGN ENGINEER. SEE TECHNICAL NOTE 6.32 FOR MANIFOLD SIZING GUIDANCE.
·DUE TO THE ADAPTATION OF THIS CHAMBER SYSTEM TO SPECIFIC SITE AND DESIGN CONSTRAINTS, IT MAY BE NECESSARY TO CUT AND COUPLE ADDITIONAL PIPE TO
STANDARD MANIFOLD COMPONENTS IN THE FIELD.
·THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET.
·THIS CHAMBER SYSTEM WAS DESIGNED WITHOUT SITE-SPECIFIC INFORMATION ON SOIL CONDITIONS OR BEARING CAPACITY. THE SITE DESIGN ENGINEER IS
RESPONSIBLE FOR DETERMINING THE SUITABILITY OF THE SOIL AND PROVIDING THE BEARING CAPACITY OF THE INSITU SOILS. THE BASE STONE DEPTH MAY BE
INCREASED OR DECREASED ONCE THIS INFORMATION IS PROVIDED.
·THE SITE DESIGN ENGINEER MUST REVIEW THE PROXIMITY OF THE CHAMBERS TO THE BUILDING/STRUCTURE. NO FOUNDATION LOADS SHALL BE TRANSMITTED TO THE
CHAMBERS. THE SITE DESIGN ENGINEER MUST CONSIDER EFFECTS OF POSSIBLE SATURATED SOILS ON BEARING CAPACITY OF SOILS AND SEEPAGE INTO BASEMENTS.
·ADS DOES NOT DESIGN OR PROVIDE MEMBRANE LINER SYSTEMS FOR CISTERNS. TO MINIMIZE THE LEAKAGE POTENTIAL OF LINER SYSTEMS, THE MEMBRANE LINER
SYSTEM SHOULD BE DESIGNED BY A KNOWLEDGEABLE GEOTEXTILE PROFESSIONAL AND INSTALLED BY A QUALIFIED CONTRACTOR.
·NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE
ACHIEVED ON SITE.
58.54'
65.66'
Project:
Chamber Model - SC-740
Units -Imperial
Number of chambers - 26
Voids in the stone (porosity) - 40 %
Base of Stone Elevation - 5000.72 ft
Amount of Stone Above Chambers - 6 in
Amount of Stone Below Chambers - 6 in
6
Area of system -1162 sf Min. Area -
Height of
System
Incremental Single
Chamber
Incremental Total
Chamber
Incremental
Stone
Incremental Ch
& St
Cumulative
Chamber Elevation 1
(inches) (cubic feet) (cubic feet) (cubic feet) (cubic feet)(cubic feet) (feet)
42 0.00 0.00 38.73 38.73 2343.63 5004.22
41 0.00 0.00 38.73 38.73 2304.90 5004.14
40 0.00 0.00 38.73 38.73 2266.17 5004.05 0cf above elevation
39 0.00 0.00 38.73 38.73 2227.43 5003.97 0cf below elevation
38 0.00 0.00 38.73 38.73 2188.70 5003.89 2343.63cf above elevation 674.8
37 0.00 0.00 38.73 38.73 2149.97 5003.80 0cf below elevation 674.8
36 0.05 1.43 38.16 39.59 2111.23 5003.72 2343.63cf between elevations 674.8 and
35 0.16 4.24 37.04 41.27 2071.64 5003.64
34 0.28 7.33 35.80 43.13 2030.37 5003.55
33 0.60 15.70 32.45 48.16 1987.24 5003.47 WQ Volume: cf
32 0.80 20.84 30.40 51.24 1939.08 5003.39 0cf below elevation
31 0.95 24.72 28.85 53.56 1887.84 5003.30
30 1.07 27.94 27.56 55.50 1834.28 5003.22
29 1.18 30.69 26.46 57.15 1778.78 5003.14 WQv achieved at elevation:
28 1.27 32.91 25.57 58.48 1721.63 5003.05
27 1.36 35.23 24.64 59.87 1663.15 5002.97
26 1.45 37.81 23.61 61.42 1603.28 5002.89
25 1.52 39.64 22.88 62.52 1541.87 5002.80
24 1.58 41.14 22.28 63.42 1479.35 5002.72
23 1.64 42.70 21.65 64.35 1415.93 5002.64
22 1.70 44.19 21.06 65.25 1351.58 5002.55
21 1.75 45.58 20.50 66.08 1286.33 5002.47
20 1.80 46.87 19.98 66.86 1220.25 5002.39
19 1.85 48.23 19.44 67.67 1153.39 5002.30
18 1.89 49.22 19.05 68.27 1085.72 5002.22
17 1.93 50.28 18.62 68.90 1017.46 5002.14
16 1.97 51.35 18.19 69.54 948.55 5002.05
15 2.01 52.26 17.83 70.09 879.01 5001.97
14 2.04 53.17 17.47 70.64 808.92 5001.89
13 2.07 53.95 17.15 71.10 738.29 5001.80
12 2.10 54.73 16.84 71.57 667.18 5001.72
11 2.13 55.43 16.56 71.99 595.61 5001.64
10 2.15 56.00 16.33 72.33 523.62 5001.55
9 2.18 56.60 16.09 72.70 451.29 5001.47
8 2.20 57.16 15.87 73.03 378.60 5001.39
7 2.21 57.39 15.78 73.17 305.57 5001.30
6 0.00 0.00 38.73 38.73 232.40 5001.22
5 0.00 0.00 38.73 38.73 193.67 5001.14
4 0.00 0.00 38.73 38.73 154.93 5001.05
3 0.00 0.00 38.73 38.73 116.20 5000.97
2 0.00 0.00 38.73 38.73 77.47 5000.89
1 0.00 0.00 38.73 38.73 38.73 5000.80
StormTech SC-740 Cumulative Storage Volumes
REV3 - FAIRWAY - N.EAST - S247917
879 sf min. area
Include Perimeter Stone in Calculations
Click Here for Metric
Max WQ Elev = 5003.00
(Equal to Inv Out South in
Storm Structure C4)
Provides 1,888 cf of WQCV
36" is top of
chambers
Fairway Lane Apartments S1 Stormtech System (East)
Water Quality Capture Volume (WQCV) Calculations
Total Area of New and/or Modified Impervious Area Contributory to Stormtech = 58,735 sq-ft
a=0.8 12-Hour Drain Time
I=90%
WQCV=0.321 Watershed-Inches
A=1.348 Acres
V=0.043 Acre-Feet
Therefore;1,887 cubic-feet of WQCV is required to be treated
=12 x 1.2
= (0.91 −1.19 +0.78
Fairway Lane ApartmentsFort Collins, COVault IDIn-Flow, WQ(cfs)Chamber TypeMimimum No. ofChambersdMinimum ReleaseRatee (cfs)Required Chamber Volume by FAA Method (cf)Mimimum No. ofChambersfProvided Number of ChambersProvided Release Ratee (cfs)Provided Chamber Volumeg(cf)Total Installed Chamber Volumeh(cf)S1 (East) 1.74 SC-74026 0.61 479 7 26 0.61 1193 1947Note: "Chamber Volume" refers to the open volume within the vaults. "Installed Chamber Volume" refers to the total volume provided, including the surrounding aggregates.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.In-Flow WQd. Number of chambers required to provide full WQCV within total installed system, including aggregate.C0.9e. Release rate per chamber times number of chambers.i1.43in/hrf. Number of chambers required to provide required FAA storage volume stored within the chamber only (no aggregate storage).A1.35acresg. Volume provided in chambers only (no aggregate storage). This number must meet or exceed the required FAA storage volume.h. System volume includes total number of chambers, plus surrounding aggregate. This number must meet or exceed the required WQCV.SC-160 SC-310MC-350025.0 34.07784.4 85.48612.0 16.04514.7 20.243.26.9 14.7109.915.0 29.31750.35 gpm/sf7.48052 gal0.133681 cf0.002228 cfs*Flow rate based on 1/2 of Nov 07 QMAX in Figure 17 of UNH Testing ReportSC-160 SC-310MC-35000.011426 0.0157240.03368718870.024 45.90 74.90Chamber Configuration SummaryTotal Required WQ Volume (cf)Individual Chamber Release Ratea(cfs)Individual ChamberVolumeb (cf)Individual Installed Chamber Volumec (cf)30.2Chamber Volume (cf)StormTech Chamber DataChamber DimensionsSC-74045.9Chamber/Aggregate Volume (cf)74.9Chamber Flow Rate Conversion (gpm/sf to cfs)Flow Rate*1 cf =1 gallon =1 GPM =Width (in)51.0Length (in)85.4Height (in)30.0Floor Area (sf)Chamber Flow RateSC-740Flow Rate/chamber (cfs)0.023586Inverts at storm structure C4 set to accommodatethis flow in 8" pipe to chambers
S1 Stormtech System (East)
Chamber Product SC-740
Design Storm WQ Required Detention Volume
Developed "C" 0.9 Quantity Detention 479 (ft3)
Area 1.35 acres
Max Release Rate 0.61 cfs
Time Time
Ft.Collins WQ
Intensity
Q100 Inflow (Runoff) Volume Outflow (Release) Volume
Storage Detention
Volume
(mins) (secs) (in/hr) (cfs)(ft3) (ft
3) (ft
3)
5 300 1.43 1.7 521 183 338
10 600 1.11 1.3 809 366 443
15 900 0.94 1.1 1028 549 479
20 1200 0.81 1.0 1181 732 449
25 1500 0.72 0.9 1312 915 397
30 1800 0.65 0.8 1422 1098 324
35 2100 0.59 0.7 1505 1281 224
40 2400 0.54 0.7 1575 1464 111
45 2700 0.50 0.6 1640 1647 -7
50 3000 0.46 0.6 1677 1830 -153
55 3300 0.44 0.5 1764 2013 -249
60 3600 0.41 0.5 1793 2196 -403
65 3900 0.39 0.5 1848 2379 -531
70 4200 0.37 0.4 1888 2562 -674
75 4500 0.35 0.4 1914 2745 -831
80 4800 0.33 0.4 1925 2928 -1003
85 5100 0.32 0.4 1983 3111 -1128
90 5400 0.31 0.4 2034 3294 -1260
95 5700 0.29 0.4 2008 3477 -1469
100 6000 0.28 0.3 2041 3660 -1619
105 6300 0.27 0.3 2067 3843 -1776
110 6600 0.26 0.3 2085 4026 -1941
115 6900 0.3 0.4 2515 4209 -1694
120 7200 0.25 0.3 2187 4392 -2205
SHEET
OFDATE:PROJECT #:DRAWN:CHECKED:THIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.4640 TRUEMAN BLVDHILLIARD, OH 430264 807/21/21S247917GGCJPR FAIRWAY LANE APARTMENTSFORT COLLINS, CODATEDRWNCHKDDESCRIPTION 12/10/21GDLGGCREVISED PER ENGINEER12-14-21MJKCTSREVISE PER COMMENTS01-12-22TSG- - -REVISED PER ENGINEER'S MARK UP0015'30'StormTechChamber System888-892-2694 | WWW.STORMTECH.COM®6" ADS N-12 DUAL WALL PERFORATED HDPE UNDERDRAIN
(SIZE TBD BY ENGINEER / SOLID OUTSIDE PERIMETER STONE)
INSPECTION PORT (TYP 3 PLACES)
PROPOSED 30" NYLOPLAST BASIN
(24" SUMP MIN)
PROPOSED OUTLET STRUCTURE
SHOWN AS 30" NYLOPLAST BASIN
(DESIGN BY ENGINEER)
ISOLATOR ROW PLUS
(SEE DETAIL / TYP 3 PLACES)
24" PREFABRICATED END CAP, PART# SC740EPE24B
TYP OF ALL SC-740 24" CONNECTIONS
CONCEPTUAL LAYOUT - SOUTHERN SYSTEM
54 STORMTECH SC-740 CHAMBERS
6 STORMTECH SC-740 END CAPS
6 STONE ABOVE (in)
6 STONE BELOW (in)
40 % STONE VOID
4,727 INSTALLED SYSTEM VOLUME (CF) (PERIMETER STONE INCLUDED)
2,313 SYSTEM AREA (ft²)
316 SYSTEM PERIMETER (ft)
CONCEPTUAL ELEVATIONS - SOUTHERN SYSTEM
5007.88 MAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED)
5001.88 MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC)
5001.38 MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC)
5001.38 MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT)
5001.38 MINIMUM ALLOWABLE GRADE (TOP OF RIGID PAVEMENT)
5000.38 TOP OF STONE
4999.88 TOP OF SC-740 CHAMBER
4997.39 24" ISOLATOR ROW PLUS MANIFOLD / CONNECTION INVERT
4997.38 BOTTOM OF SC-740 CHAMBER
4996.88 UNDERDRAIN INVERT
4996.88 BOTTOM OF STONE
24" PREFABRICATED END CAP, PART# SC740EPE24BR
TYP OF ALL SC-740 24" ISOLATOR ROW PLUS CONNECTIONS
THERMOPLASTIC LINER
(SEE TECHNICAL NOTE 6.50 / PROVIDED BY OTHERS / DESIGN BY OTHERS)
NOTES
·MANIFOLD SIZE TO BE DETERMINED BY SITE DESIGN ENGINEER. SEE TECHNICAL NOTE 6.32 FOR MANIFOLD SIZING GUIDANCE.
·DUE TO THE ADAPTATION OF THIS CHAMBER SYSTEM TO SPECIFIC SITE AND DESIGN CONSTRAINTS, IT MAY BE NECESSARY TO CUT AND COUPLE ADDITIONAL PIPE TO
STANDARD MANIFOLD COMPONENTS IN THE FIELD.
·THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET.
·THIS CHAMBER SYSTEM WAS DESIGNED WITHOUT SITE-SPECIFIC INFORMATION ON SOIL CONDITIONS OR BEARING CAPACITY. THE SITE DESIGN ENGINEER IS
RESPONSIBLE FOR DETERMINING THE SUITABILITY OF THE SOIL AND PROVIDING THE BEARING CAPACITY OF THE INSITU SOILS. THE BASE STONE DEPTH MAY BE
INCREASED OR DECREASED ONCE THIS INFORMATION IS PROVIDED.
·THE SITE DESIGN ENGINEER MUST REVIEW THE PROXIMITY OF THE CHAMBERS TO THE BUILDING/STRUCTURE. NO FOUNDATION LOADS SHALL BE TRANSMITTED TO THE
CHAMBERS. THE SITE DESIGN ENGINEER MUST CONSIDER EFFECTS OF POSSIBLE SATURATED SOILS ON BEARING CAPACITY OF SOILS AND SEEPAGE INTO BASEMENTS.
·ADS DOES NOT DESIGN OR PROVIDE MEMBRANE LINER SYSTEMS FOR CISTERNS. TO MINIMIZE THE LEAKAGE POTENTIAL OF LINER SYSTEMS, THE MEMBRANE LINER
SYSTEM SHOULD BE DESIGNED BY A KNOWLEDGEABLE GEOTEXTILE PROFESSIONAL AND INSTALLED BY A QUALIFIED CONTRACTOR.
·NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE
ACHIEVED ON SITE.
141.46'
129.71'
PROPOSED 30" NYLOPLAST BASIN
(FOR ISOLATOR ROW ACCESS
/24" MIN SUMP)16.35'13.75'24" X 24" ADS N-12 BOTTOM MANIFOLD
INVERT 0.1" ABOVE CHAMBER BASE
(SEE NOTES / TYP 2 PLACES)
24" ADS N-12 BOTTOM CONNECTION
INVERT 0.1" ABOVE CHAMBER BASE
(SEE NOTES/TYP 4 PLACES)
PROPOSED 30" NYLOPLAST BASIN
(24" SUMP MIN)
Project:
Chamber Model - SC-740
Units -Imperial
Number of chambers - 54
Voids in the stone (porosity) - 40 %
Base of Stone Elevation - 4996.88 ft
Amount of Stone Above Chambers - 6 in
Amount of Stone Below Chambers - 6 in
6
Area of system -2313 sf Min. Area -
Height of
System
Incremental Single
Chamber
Incremental Total
Chamber
Incremental
Stone
Incremental Ch
& St
Cumulative
Chamber Elevation 1
(inches) (cubic feet) (cubic feet) (cubic feet) (cubic feet)(cubic feet) (feet)
42 0.00 0.00 77.10 77.10 4727.01 5000.38
41 0.00 0.00 77.10 77.10 4649.91 5000.30
40 0.00 0.00 77.10 77.10 4572.81 5000.21 0cf above elevation
39 0.00 0.00 77.10 77.10 4495.71 5000.13 0cf below elevation
38 0.00 0.00 77.10 77.10 4418.61 5000.05 4727.01cf above elevation 674.8
37 0.00 0.00 77.10 77.10 4341.51 4999.96 0cf below elevation 674.8
36 0.05 2.97 75.91 78.88 4264.41 4999.88 4727.01cf between elevations 674.8 and
35 0.16 8.80 73.58 82.38 4185.53 4999.80
34 0.28 15.22 71.01 86.23 4103.15 4999.71
33 0.60 32.61 64.05 96.67 4016.91 4999.63 WQ Volume: cf
32 0.80 43.29 59.78 103.08 3920.24 4999.55 0cf below elevation
31 0.95 51.34 56.57 107.90 3817.17 4999.46
30 1.07 58.02 53.89 111.91 3709.27 4999.38
29 1.18 63.75 51.60 115.35 3597.35 4999.30 WQv achieved at elevation:
28 1.27 68.35 49.76 118.11 3482.00 4999.21
27 1.36 73.17 47.83 121.00 3363.90 4999.13
26 1.45 78.52 45.69 124.21 3242.89 4999.05
25 1.52 82.34 44.17 126.50 3118.68 4998.96
24 1.58 85.45 42.92 128.37 2992.18 4998.88
23 1.64 88.68 41.63 130.31 2863.81 4998.80
22 1.70 91.77 40.39 132.16 2733.50 4998.71
21 1.75 94.66 39.24 133.89 2601.34 4998.63
20 1.80 97.35 38.16 135.51 2467.44 4998.55
19 1.85 100.17 37.03 137.20 2331.93 4998.46
18 1.89 102.23 36.21 138.44 2194.73 4998.38
17 1.93 104.44 35.33 139.76 2056.29 4998.30
16 1.97 106.65 34.44 141.09 1916.53 4998.21
15 2.01 108.54 33.69 142.22 1775.44 4998.13
14 2.04 110.43 32.93 143.36 1633.22 4998.05
13 2.07 112.05 32.28 144.33 1489.86 4997.96
12 2.10 113.67 31.63 145.30 1345.54 4997.88
11 2.13 115.12 31.05 146.17 1200.24 4997.80
10 2.15 116.31 30.58 146.88 1054.07 4997.71
9 2.18 117.56 30.08 147.64 907.18 4997.63
8 2.20 118.71 29.62 148.33 759.54 4997.55
7 2.21 119.20 29.42 148.62 611.22 4997.46
6 0.00 0.00 77.10 77.10 462.60 4997.38
5 0.00 0.00 77.10 77.10 385.50 4997.30
4 0.00 0.00 77.10 77.10 308.40 4997.21
3 0.00 0.00 77.10 77.10 231.30 4997.13
2 0.00 0.00 77.10 77.10 154.20 4997.05
1 0.00 0.00 77.10 77.10 77.10 4996.96
StormTech SC-740 Cumulative Storage Volumes
REV3 - FAIRWAY - SOUTHERN - S247917
1825 sf min. area
Include Perimeter Stone in Calculations
Click Here for Metric
Max WQ Elev = 4999.86
(Equal to Inv Out East in
Storm Structure A6)
Provides 4,264 cf of WQCV
36" is top of
chambers
Fairway Lane Apartments S2 Stormtech System (South)
Water Quality Capture Volume (WQCV) Calculations
Total Area of New and/or Modified Impervious Area Contributory to Stormtech = 125,846 sq-ft
a=0.8 12-Hour Drain Time
I=90%
WQCV=0.321 Watershed-Inches
A=2.889 Acres
V=0.093 Acre-Feet
Therefore;4,042 cubic-feet of WQCV is required to be treated
=12 x 1.2
= (0.91 −1.19 +0.78
Fairway Lane ApartmentsFort Collins, COVault IDIn-Flow, WQ(cfs)Chamber TypeMimimum No. ofChambersdMinimum ReleaseRatee (cfs)Required Chamber Volume by FAA Method (cf)Mimimum No. ofChambersfProvided Number of ChambersProvided Release Ratee (cfs)Provided Chamber Volumeg(cf)Total Installed Chamber Volumeh(cf)S2 3.72 SC-74054 1.27 1057 24 54 1.27 2479 4045Note: "Chamber Volume" refers to the open volume within the vaults. "Installed Chamber Volume" refers to the total volume provided, including the surrounding aggregates.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.In-Flow WQd. Number of chambers required to provide full WQCV within total installed system, including aggregate.C0.9e. Release rate per chamber times number of chambers.i1.43in/hrf. Number of chambers required to provide required FAA storage volume stored within the chamber only (no aggregate storage).A2.89acresg. Volume provided in chambers only (no aggregate storage). This number must meet or exceed the required FAA storage volume.h. System volume includes total number of chambers, plus surrounding aggregate. This number must meet or exceed the required WQCV.SC-160 SC-310MC-350025.0 34.07784.4 85.48612.0 16.04514.7 20.243.26.9 14.7109.915.0 29.31750.35 gpm/sf7.48052 gal0.133681 cf0.002228 cfs*Flow rate based on 1/2 of Nov 07 QMAX in Figure 17 of UNH Testing ReportSC-160 SC-310MC-35000.011426 0.0157240.033687Chamber Flow RateSC-740Flow Rate/chamber (cfs)0.023586Chamber/Aggregate Volume (cf)74.9Chamber Flow Rate Conversion (gpm/sf to cfs)Flow Rate*1 cf =1 gallon =1 GPM =Width (in)51.0Length (in)85.4Height (in)30.0Floor Area (sf)30.2Chamber Volume (cf)StormTech Chamber DataChamber DimensionsSC-74045.940420.024 45.90 74.90Chamber Configuration SummaryTotal Required WQ Volume (cf)Individual Chamber Release Ratea(cfs)Individual ChamberVolumeb (cf)Individual Installed Chamber Volumec (cf)Inverts at storm structure A6 set to accommodatethis flow in 10" pipe to chambers
S2 Stormtech System (South)
Chamber Product SC-740
Design Storm WQ Required Detention Volume
Developed "C" 0.9 Quantity Detention 1057 (ft3)
Area 2.89 acres
Max Release Rate 1.27 cfs
Time Time
Ft.Collins
WQ
Intensity
Q100
Inflow (Runoff) Volume Outflow (Release) Volume Storage Detention
Volume
(mins) (secs) (in/hr) (cfs)(ft3) (ft
3) (ft
3)
5 300 1.43 3.7 1116 381 735
10 600 1.11 2.9 1732 762 970
15 900 0.94 2.4 2200 1143 1057
20 1200 0.81 2.1 2528 1524 1004
25 1500 0.72 1.9 2809 1905 904
30 1800 0.65 1.7 3043 2286 757
35 2100 0.59 1.5 3223 2667 556
40 2400 0.54 1.4 3371 3048 323
45 2700 0.50 1.3 3511 3429 82
50 3000 0.46 1.2 3589 3810 -221
55 3300 0.44 1.1 3777 4191 -414
60 3600 0.41 1.1 3839 4572 -733
65 3900 0.39 1.0 3956 4953 -997
70 4200 0.37 1.0 4042 5334 -1292
75 4500 0.35 0.9 4097 5715 -1618
80 4800 0.33 0.9 4120 6096 -1976
85 5100 0.32 0.8 4245 6477 -2232
90 5400 0.31 0.8 4354 6858 -2504
95 5700 0.29 0.8 4299 7239 -2940
100 6000 0.28 0.7 4370 7620 -3250
105 6300 0.27 0.7 4424 8001 -3577
110 6600 0.26 0.7 4463 8382 -3919
115 6900 0.3 0.8 5384 8763 -3379
120 7200 0.25 0.7 4682 9144 -4462
SHEET
OFDATE:PROJECT #:DRAWN:CHECKED:THIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.4640 TRUEMAN BLVDHILLIARD, OH 430265 807/21/21S247917GGCJPR FAIRWAY LANE APARTMENTSFORT COLLINS, CODATEDRWNCHKDDESCRIPTION 12/10/21GDLGGCREVISED PER ENGINEER12-14-21MJKCTSREVISE PER COMMENTS01-12-22TSG- - -REVISED PER ENGINEER'S MARK UPStormTechChamber System888-892-2694 | WWW.STORMTECH.COM®ACCEPTABLE FILL MATERIALS: STORMTECH SC-740 CHAMBER SYSTEMS
PLEASE NOTE:
1.THE LISTED AASHTO DESIGNATIONS ARE FOR GRADATIONS ONLY. THE STONE MUST ALSO BE CLEAN, CRUSHED, ANGULAR. FOR EXAMPLE, A SPECIFICATION FOR #4 STONE WOULD STATE: "CLEAN, CRUSHED, ANGULAR NO. 4 (AASHTO M43) STONE".
2.STORMTECH COMPACTION REQUIREMENTS ARE MET FOR 'A' LOCATION MATERIALS WHEN PLACED AND COMPACTED IN 6" (150 mm) (MAX) LIFTS USING TWO FULL COVERAGES WITH A VIBRATORY COMPACTOR.
3.WHERE INFILTRATION SURFACES MAY BE COMPROMISED BY COMPACTION, FOR STANDARD DESIGN LOAD CONDITIONS, A FLAT SURFACE MAY BE ACHIEVED BY RAKING OR DRAGGING WITHOUT COMPACTION EQUIPMENT. FOR SPECIAL LOAD DESIGNS, CONTACT STORMTECH FOR
COMPACTION REQUIREMENTS.
4.ONCE LAYER 'C' IS PLACED, ANY SOIL/MATERIAL CAN BE PLACED IN LAYER 'D' UP TO THE FINISHED GRADE. MOST PAVEMENT SUBBASE SOILS CAN BE USED TO REPLACE THE MATERIAL REQUIREMENTS OF LAYER 'C' OR 'D' AT THE SITE DESIGN ENGINEER'S DISCRETION.
NOTES:
1.CHAMBERS SHALL MEET THE REQUIREMENTS OF ASTM F2418-16a, "STANDARD SPECIFICATION FOR POLYPROPYLENE (PP) CORRUGATED WALL STORMWATER COLLECTION CHAMBERS".
2.SC-740 CHAMBERS SHALL BE DESIGNED IN ACCORDANCE WITH ASTM F2787 "STANDARD PRACTICE FOR STRUCTURAL DESIGN OF THERMOPLASTIC CORRUGATED WALL STORMWATER COLLECTION CHAMBERS".
3.THE SITE DESIGN ENGINEER IS RESPONSIBLE FOR ASSESSING THE BEARING RESISTANCE (ALLOWABLE BEARING CAPACITY) OF THE SUBGRADE SOILS AND THE DEPTH OF FOUNDATION STONE WITH
CONSIDERATION FOR THE RANGE OF EXPECTED SOIL MOISTURE CONDITIONS.
4.PERIMETER STONE MUST BE EXTENDED HORIZONTALLY TO THE EXCAVATION WALL FOR BOTH VERTICAL AND SLOPED EXCAVATION WALLS.
5.REQUIREMENTS FOR HANDLING AND INSTALLATION:
·TO MAINTAIN THE WIDTH OF CHAMBERS DURING SHIPPING AND HANDLING, CHAMBERS SHALL HAVE INTEGRAL, INTERLOCKING STACKING LUGS.
·TO ENSURE A SECURE JOINT DURING INSTALLATION AND BACKFILL, THE HEIGHT OF THE CHAMBER JOINT SHALL NOT BE LESS THAN 2”.
·TO ENSURE THE INTEGRITY OF THE ARCH SHAPE DURING INSTALLATION, a) THE ARCH STIFFNESS CONSTANT AS DEFINED IN SECTION 6.2.8 OF ASTM F2418 SHALL BE GREATER THAN OR EQUAL TO 550
LBS/IN/IN. AND b) TO RESIST CHAMBER DEFORMATION DURING INSTALLATION AT ELEVATED TEMPERATURES (ABOVE 73° F / 23° C), CHAMBERS SHALL BE PRODUCED FROM REFLECTIVE GOLD OR YELLOW
COLORS.
MATERIAL LOCATION DESCRIPTION AASHTO MATERIAL
CLASSIFICATIONS COMPACTION / DENSITY REQUIREMENT
D
FINAL FILL: FILL MATERIAL FOR LAYER 'D' STARTS FROM THE
TOP OF THE 'C' LAYER TO THE BOTTOM OF FLEXIBLE
PAVEMENT OR UNPAVED FINISHED GRADE ABOVE. NOTE THAT
PAVEMENT SUBBASE MAY BE PART OF THE 'D' LAYER.
ANY SOIL/ROCK MATERIALS, NATIVE SOILS, OR PER ENGINEER'S PLANS.
CHECK PLANS FOR PAVEMENT SUBGRADE REQUIREMENTS.N/A
PREPARE PER SITE DESIGN ENGINEER'S PLANS. PAVED
INSTALLATIONS MAY HAVE STRINGENT MATERIAL AND
PREPARATION REQUIREMENTS.
C
INITIAL FILL: FILL MATERIAL FOR LAYER 'C' STARTS FROM THE
TOP OF THE EMBEDMENT STONE ('B' LAYER) TO 18" (450 mm)
ABOVE THE TOP OF THE CHAMBER. NOTE THAT PAVEMENT
SUBBASE MAY BE A PART OF THE 'C' LAYER.
GRANULAR WELL-GRADED SOIL/AGGREGATE MIXTURES, <35% FINES OR
PROCESSED AGGREGATE.
MOST PAVEMENT SUBBASE MATERIALS CAN BE USED IN LIEU OF THIS
LAYER.
AASHTO M145¹
A-1, A-2-4, A-3
OR
AASHTO M43¹
3, 357, 4, 467, 5, 56, 57, 6, 67, 68, 7, 78, 8, 89, 9, 10
BEGIN COMPACTIONS AFTER 12" (300 mm) OF MATERIAL OVER
THE CHAMBERS IS REACHED. COMPACT ADDITIONAL LAYERS IN
6" (150 mm) MAX LIFTS TO A MIN. 95% PROCTOR DENSITY FOR
WELL GRADED MATERIAL AND 95% RELATIVE DENSITY FOR
PROCESSED AGGREGATE MATERIALS. ROLLER GROSS
VEHICLE WEIGHT NOT TO EXCEED 12,000 lbs (53 kN). DYNAMIC
FORCE NOT TO EXCEED 20,000 lbs (89 kN).
B
EMBEDMENT STONE: FILL SURROUNDING THE CHAMBERS
FROM THE FOUNDATION STONE ('A' LAYER) TO THE 'C' LAYER
ABOVE.
CLEAN, CRUSHED, ANGULAR STONE AASHTO M43¹
3, 357, 4, 467, 5, 56, 57 NO COMPACTION REQUIRED.
A FOUNDATION STONE: FILL BELOW CHAMBERS FROM THE
SUBGRADE UP TO THE FOOT (BOTTOM) OF THE CHAMBER.CLEAN, CRUSHED, ANGULAR STONE AASHTO M43¹
3, 357, 4, 467, 5, 56, 57 PLATE COMPACT OR ROLL TO ACHIEVE A FLAT SURFACE.2,3
18"
(450 mm) MIN*
8'
(2.4 m)
MAX
6" (150 mm) MIN
D
C
B
A
12" (300 mm) MIN 12" (300 mm) MIN51" (1295 mm)6"
(150 mm) MIN
1 LAYER OF ADS GEOSYNTHETICS NON-WOVEN GEOTEXTILE ON BOTH SIDES OF
THERMOPLASTIC LINER ALL AROUND CLEAN, CRUSHED, ANGULAR STONE IN A & B LAYERS.
SEE ADS TECHNICAL NOTE 6.50 FOR NON-WOVEN WEIGHT RECOMMENDATIONS.
30"
(762 mm)
DEPTH OF STONE TO BE DETERMINED
BY SITE DESIGN ENGINEER 6" (150 mm) MIN
*TO BOTTOM OF FLEXIBLE PAVEMENT. FOR UNPAVED
INSTALLATIONS WHERE RUTTING FROM VEHICLES MAY OCCUR,
INCREASE COVER TO 24" (600 mm).
PERIMETER STONE
(SEE NOTE 4)
SC-740 END CAP
SUBGRADE SOILS
(SEE NOTE 3)
PAVEMENT LAYER (DESIGNED
BY SITE DESIGN ENGINEER)
1 LAYER OF ADS GEOSYNTHETICS NON-WOVEN GEOTEXTILE BEWTEEN COVER STONE AND C LAYER.
EXCAVATION WALL
(CAN BE SLOPED OR VERTICAL)
THERMOPLASTIC LINER DETAIL
NON-WOVEN
GEOTEXTILE
EARTH
THERMOPLASTIC
LINER
OVERLAP ON TOP
SEVERAL INCHES
TO ANCHOR (PER
MANUFACTURER'S
RECOMMENDATIONS)
ANGULAR
STONE
NON-WOVEN
GEOTEXTILE
**THIS CROSS SECTION DETAIL REPRESENTS
MINIMUM REQUIREMENTS FOR INSTALLATION.
PLEASE SEE THE LAYOUT SHEET(S) FOR
PROJECT SPECIFIC REQUIREMENTS.
SHEET
OFDATE:PROJECT #:DRAWN:CHECKED:THIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.4640 TRUEMAN BLVDHILLIARD, OH 430266 807/21/21S247917GGCJPR FAIRWAY LANE APARTMENTSFORT COLLINS, CODATEDRWNCHKDDESCRIPTION 12/10/21GDLGGCREVISED PER ENGINEER12-14-21MJKCTSREVISE PER COMMENTS01-12-22TSG- - -REVISED PER ENGINEER'S MARK UPStormTechChamber System888-892-2694 | WWW.STORMTECH.COM®INSPECTION & MAINTENANCE
STEP 1)INSPECT ISOLATOR ROW PLUS FOR SEDIMENT
A.INSPECTION PORTS (IF PRESENT)
A.1.REMOVE/OPEN LID ON NYLOPLAST INLINE DRAIN
A.2.REMOVE AND CLEAN FLEXSTORM FILTER IF INSTALLED
A.3.USING A FLASHLIGHT AND STADIA ROD, MEASURE DEPTH OF SEDIMENT AND RECORD ON MAINTENANCE LOG
A.4.LOWER A CAMERA INTO ISOLATOR ROW PLUS FOR VISUAL INSPECTION OF SEDIMENT LEVELS (OPTIONAL)
A.5.IF SEDIMENT IS AT, OR ABOVE, 3" (80 mm) PROCEED TO STEP 2. IF NOT, PROCEED TO STEP 3.
B.ALL ISOLATOR PLUS ROWS
B.1.REMOVE COVER FROM STRUCTURE AT UPSTREAM END OF ISOLATOR ROW PLUS
B.2.USING A FLASHLIGHT, INSPECT DOWN THE ISOLATOR ROW PLUS THROUGH OUTLET PIPE
i)MIRRORS ON POLES OR CAMERAS MAY BE USED TO AVOID A CONFINED SPACE ENTRY
ii)FOLLOW OSHA REGULATIONS FOR CONFINED SPACE ENTRY IF ENTERING MANHOLE
B.3.IF SEDIMENT IS AT, OR ABOVE, 3" (80 mm) PROCEED TO STEP 2. IF NOT, PROCEED TO STEP 3.
STEP 2)CLEAN OUT ISOLATOR ROW PLUS USING THE JETVAC PROCESS
A.A FIXED CULVERT CLEANING NOZZLE WITH REAR FACING SPREAD OF 45" (1.1 m) OR MORE IS PREFERRED
B.APPLY MULTIPLE PASSES OF JETVAC UNTIL BACKFLUSH WATER IS CLEAN
C.VACUUM STRUCTURE SUMP AS REQUIRED
STEP 3)REPLACE ALL COVERS, GRATES, FILTERS, AND LIDS; RECORD OBSERVATIONS AND ACTIONS.
STEP 4)INSPECT AND CLEAN BASINS AND MANHOLES UPSTREAM OF THE STORMTECH SYSTEM.
NOTES
1.INSPECT EVERY 6 MONTHS DURING THE FIRST YEAR OF OPERATION. ADJUST THE INSPECTION INTERVAL BASED ON PREVIOUS
OBSERVATIONS OF SEDIMENT ACCUMULATION AND HIGH WATER ELEVATIONS.
2.CONDUCT JETTING AND VACTORING ANNUALLY OR WHEN INSPECTION SHOWS THAT MAINTENANCE IS NECESSARY.
SC-740 ISOLATOR ROW PLUS DETAIL
NTS
SC-740 END CAP
OPTIONAL INSPECTION PORT
SC-740 CHAMBER
COVER ENTIRE ISOLATOR ROW PLUS WITH ADS
GEOSYNTHETICS 601T NON-WOVEN GEOTEXTILE
8' (2.4 m) MIN WIDE
STORMTECH HIGHLY RECOMMENDS
FLEXSTORM INSERTS IN ANY UPSTREAM
STRUCTURES WITH OPEN GRATES
ONE LAYER OF ADSPLUS125 WOVEN GEOTEXTILE BETWEEN
FOUNDATION STONE AND CHAMBERS
5' (1.5 m) MIN WIDE CONTINUOUS FABRIC WITHOUT SEAMS
ELEVATED BYPASS MANIFOLD
24" (600 mm) HDPE ACCESS PIPE REQUIRED
USE FACTORY PRE-FABRICATED END CAP
WITH FLAMP PART #: SC740EPE24BR
NYLOPLAST
SUMP DEPTH TBD BY
SITE DESIGN ENGINEER
(24" [600 mm] MIN RECOMMENDED)
NOTE:
INSPECTION PORTS MAY BE CONNECTED THROUGH ANY CHAMBER CORRUGATION CREST.
STORMTECH CHAMBER
CONCRETE COLLAR
PAVEMENT
12" (300 mm) MIN WIDTH
CONCRETE SLAB
6" (150 mm) MIN THICKNESS
4" PVC INSPECTION PORT DETAIL
(SC SERIES CHAMBER)
NTS
8" NYLOPLAST INSPECTION PORT
BODY (PART# 2708AG4IPKIT) OR
TRAFFIC RATED BOX W/SOLID
LOCKING COVER
CONCRETE COLLAR NOT REQUIRED
FOR UNPAVED APPLICATIONS
4" (100 mm)
SDR 35 PIPE
4" (100 mm) INSERTA TEE
TO BE CENTERED ON
CORRUGATION CREST
INSPECTION PORT (SEE CHAMBER
SYSTEM LAYOUTS FOR LOCATIONS)
SHEET
OFDATE:PROJECT #:DRAWN:CHECKED:THIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.4640 TRUEMAN BLVDHILLIARD, OH 430267 807/21/21S247917GGCJPR FAIRWAY LANE APARTMENTSFORT COLLINS, CODATEDRWNCHKDDESCRIPTION 12/10/21GDLGGCREVISED PER ENGINEER12-14-21MJKCTSREVISE PER COMMENTS01-12-22TSG- - -REVISED PER ENGINEER'S MARK UPStormTechChamber System888-892-2694 | WWW.STORMTECH.COM®PART #STUB A B C
SC740EPE06T / SC740EPE06TPC 6" (150 mm)10.9" (277 mm)18.5" (470 mm)---
SC740EPE06B / SC740EPE06BPC ---0.5" (13 mm)
SC740EPE08T /SC740EPE08TPC 8" (200 mm)12.2" (310 mm)16.5" (419 mm)---
SC740EPE08B / SC740EPE08BPC ---0.6" (15 mm)
SC740EPE10T / SC740EPE10TPC 10" (250 mm)13.4" (340 mm)14.5" (368 mm)---
SC740EPE10B / SC740EPE10BPC ---0.7" (18 mm)
SC740EPE12T / SC740EPE12TPC 12" (300 mm)14.7" (373 mm)12.5" (318 mm)---
SC740EPE12B / SC740EPE12BPC ---1.2" (30 mm)
SC740EPE15T / SC740EPE15TPC 15" (375 mm)18.4" (467 mm)9.0" (229 mm)---
SC740EPE15B / SC740EPE15BPC ---1.3" (33 mm)
SC740EPE18T / SC740EPE18TPC 18" (450 mm)19.7" (500 mm)5.0" (127 mm)---
SC740EPE18B / SC740EPE18BPC ---1.6" (41 mm)
SC740EPE24B*24" (600 mm)18.5" (470 mm)---0.1" (3 mm)
SC740EPE24BR*24" (600 mm)18.5" (470 mm)---0.1" (3 mm)
ALL STUBS, EXCEPT FOR THE SC740EPE24B/SC740EPE24BR ARE PLACED AT BOTTOM OF END CAP SUCH THAT THE OUTSIDE
DIAMETER OF THE STUB IS FLUSH WITH THE BOTTOM OF THE END CAP. FOR ADDITIONAL INFORMATION CONTACT
STORMTECH AT 1-888-892-2694.
* FOR THE SC740EPE24B/SC740EPE24BR THE 24" (600 mm) STUB LIES BELOW THE BOTTOM OF THE END CAP APPROXIMATELY
1.75" (44 mm). BACKFILL MATERIAL SHOULD BE REMOVED FROM BELOW THE N-12 STUB SO THAT THE FITTING SITS LEVEL.
NOTE: ALL DIMENSIONS ARE NOMINAL
NOMINAL CHAMBER SPECIFICATIONS
SIZE (W X H X INSTALLED LENGTH)51.0" X 30.0" X 85.4" (1295 mm X 762 mm X 2169 mm)
CHAMBER STORAGE 45.9 CUBIC FEET (1.30 m³)
MINIMUM INSTALLED STORAGE*74.9 CUBIC FEET (2.12 m³)
WEIGHT 75.0 lbs.(33.6 kg)
*ASSUMES 6" (152 mm) STONE ABOVE, BELOW, AND BETWEEN CHAMBERS
PRE-FAB STUB AT BOTTOM OF END CAP WITH FLAMP END WITH "BR"
PRE-FAB STUBS AT BOTTOM OF END CAP FOR PART NUMBERS ENDING WITH "B"
PRE-FAB STUBS AT TOP OF END CAP FOR PART NUMBERS ENDING WITH "T"
PRE-CORED END CAPS END WITH "PC"
SC-740 TECHNICAL SPECIFICATION
NTS
90.7" (2304 mm) ACTUAL LENGTH 85.4" (2169 mm) INSTALLED LENGTH
BUILD ROW IN THIS DIRECTION
A A
C
B
51.0"
(1295 mm)
30.0"
(762 mm)
45.9" (1166 mm)12.2"
(310 mm)
29.3"
(744 mm)
OVERLAP NEXT CHAMBER HERE
(OVER SMALL CORRUGATION)
START END
UNDERDRAIN DETAIL
NTS
A
A
B B
SECTION A-A
SECTION B-B
NUMBER AND SIZE OF UNDERDRAINS PER SITE DESIGN ENGINEER
4" (100 mm) TYP FOR SC-310 & SC-160LP SYSTEMS
6" (150 mm) TYP FOR SC-740, DC-780, MC-3500 & MC-4500 SYSTEMS
OUTLET MANIFOLD
STORMTECH
END CAP
STORMTECH
CHAMBERS
STORMTECH
CHAMBER
STORMTECH
END CAP
DUAL WALL
PERFORATED
HDPE
UNDERDRAIN
ADS GEOSYNTHETICS 601T
NON-WOVEN GEOTEXTILE
ADS GEOSYNTHETICS 601T
NON-WOVEN GEOTEXTILE
FOUNDATION STONE
BENEATH CHAMBERS
FOUNDATION STONE
BENEATH CHAMBERS
SHEET
OFDATE:PROJECT #:DRAWN:CHECKED:THIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS.4640 TRUEMAN BLVDHILLIARD, OH 430268 807/21/21S247917GGCJPR FAIRWAY LANE APARTMENTSFORT COLLINS, CODATEDRWNCHKDDESCRIPTION 12/10/21GDLGGCREVISED PER ENGINEER12-14-21MJKCTSREVISE PER COMMENTS01-12-22TSG- - -REVISED PER ENGINEER'S MARK UPTRAFFIC LOADS: CONCRETE DIMENSIONS
ARE FOR GUIDELINE PUPOSES ONLY.
ACTUAL CONCRETE SLAB MUST BE
DESIGNED GIVING CONSIDERATION FOR
LOCAL SOIL CONDITIONS, TRAFFIC
LOADING & OTHER APPLICABLE DESIGN
FACTORS
ADAPTER ANGLES VARIABLE 0°- 360°
ACCORDING TO PLANS
A
18" (457 mm)
MIN WIDTH
AASHTO H-20 CONCRETE SLAB
8" (203 mm) MIN THICKNESS
VARIABLE SUMP DEPTH
ACCORDING TO PLANS
[6" (152 mm) MIN ON 8-24" (200-600 mm),
10" (254 mm) MIN ON 30" (750 mm)]
4" (102 mm) MIN ON 8-24" (200-600 mm)
6" (152 mm) MIN ON 30" (750 mm)
12" (610 mm) MIN
(FOR AASHTO H-20)
INVERT ACCORDING TO
PLANS/TAKE OFF
BACKFILL MATERIAL BELOW AND TO SIDES
OF STRUCTURE SHALL BE ASTM D2321
CLASS I OR II CRUSHED STONE OR GRAVEL
AND BE PLACED UNIFORMLY IN 12" (305 mm)
LIFTS AND COMPACTED TO MIN OF 90%
INTEGRATED DUCTILE IRON
FRAME & GRATE/SOLID TO
MATCH BASIN O.D.
NYLOPLAST DRAIN BASIN
NTS
NOTES
1.8-30" (200-750 mm) GRATES/SOLID COVERS SHALL BE DUCTILE IRON PER ASTM A536
GRADE 70-50-05
2.12-30" (300-750 mm) FRAMES SHALL BE DUCTILE IRON PER ASTM A536 GRADE 70-50-05
3.DRAIN BASIN TO BE CUSTOM MANUFACTURED ACCORDING TO PLAN DETAILS
4.DRAINAGE CONNECTION STUB JOINT TIGHTNESS SHALL CONFORM TO ASTM D3212
FOR CORRUGATED HDPE (ADS & HANCOR DUAL WALL) & SDR 35 PVC
5.FOR COMPLETE DESIGN AND PRODUCT INFORMATION: WWW.NYLOPLAST-US.COM
6.TO ORDER CALL: 800-821-6710
A PART #GRATE/SOLID COVER OPTIONS
8"
(200 mm)2808AG PEDESTRIAN LIGHT
DUTY
STANDARD LIGHT
DUTY SOLID LIGHT DUTY
10"
(250 mm)2810AG PEDESTRIAN LIGHT
DUTY
STANDARD LIGHT
DUTY SOLID LIGHT DUTY
12"
(300 mm)2812AG PEDESTRIAN
AASHTO H-10
STANDARD AASHTO
H-20
SOLID
AASHTO H-20
15"
(375 mm)2815AG PEDESTRIAN
AASHTO H-10
STANDARD AASHTO
H-20
SOLID
AASHTO H-20
18"
(450 mm)2818AG PEDESTRIAN
AASHTO H-10
STANDARD AASHTO
H-20
SOLID
AASHTO H-20
24"
(600 mm)2824AG PEDESTRIAN
AASHTO H-10
STANDARD AASHTO
H-20
SOLID
AASHTO H-20
30"
(750 mm)2830AG PEDESTRIAN
AASHTO H-20
STANDARD AASHTO
H-20
SOLID
AASHTO H-20
VARIOUS TYPES OF INLET AND
OUTLET ADAPTERS AVAILABLE:
4-30" (100-750 mm) FOR
CORRUGATED HDPE
WATERTIGHT JOINT
(CORRUGATED HDPE SHOWN)Nyloplast770-932-2443 | WWW.NYLOPLAST-US.COM®
APPENDIX F Fairway Lane Apartments – Fort Collins, CO
20065