HomeMy WebLinkAboutZIEGLER-HARVEST PARK - FDP - FDP140022 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTFINAL DRAINAGE REPORT
Harvest Park - Ziegler Mixed Use Lot 2
Prepared for:
Architecture West, LLC
4710 South College Ave
Fort Collins, CO 80525
(970) 207-0424
Prepared by:
Interwest Consulting Group
1218 West Ash, Suite C
Windsor, Colorado 80550
(970) 674-3300
September 10, 2014
Job Number 1054-095-00
iii
TABLE OF CONTENTS
TABLE OF CONTENTS ............................................................................................................... iii
1. GENERAL LOCATION AND DESCRIPTION ...................................................................... 1
1.1 Location ............................................................................................................................ 1
1.2 Description of Property .................................................................................................... 1
2. DRAINAGE BASINS AND SUB-BASINS ............................................................................ 2
2.1 Major Basin Description .................................................................................................. 2
2.2 Sub-basin Description ...................................................................................................... 2
3. DRAINAGE DESIGN CRITERIA .......................................................................................... 3
3.1 Regulations ....................................................................................................................... 3
3.2 Directly Connected Impervious Area (DCIA) Discussion ............................................... 3
3.3 Development Criteria Reference and Constraints ............................................................ 4
3.4 Hydrologic Criteria ........................................................................................................... 4
3.5 Hydraulic Criteria ............................................................................................................. 5
3.6 Floodplain Regulations Compliance ................................................................................ 5
4. DRAINAGE FACILITY DESIGN ........................................................................................... 5
4.1 General Concept ............................................................................................................... 5
4.2 Specific Flow Routing ...................................................................................................... 6
5. CONCLUSIONS ...................................................................................................................... 9
5.1 Compliance with Standards .............................................................................................. 9
5.2 Drainage Concept ............................................................................................................. 9
6. REFERENCES ....................................................................................................................... 10
APPENDIX A-VICINITY MAP AND DRAINAGE PLAN ......................................................... A
APPENDIX B-HYDROLOGIC COMPUTATIONS ..................................................................... B
APPENDIX C-HYDRAULIC CALCULATIONS ......................................................................... C
APPENDIX D-WATER QUALITY POND SIZING .................................................................... D
APPENDIX E-FLOODPLAIN INFORMATION........................................................................... E
1
1. GENERAL LOCATION AND DESCRIPTION
1.1 Location
The Harvest Park / Ziegler Mixed Use development is located in southeast Fort Collins.
It is located in the Southwest Quarter of Section 5, Township 6 North, Range 68 West of
the Sixth Principal Meridian, in the City of Fort Collins, Larimer County, Colorado. See
the location map in Appendix A.
The project is located west of Zeigler Road and the property will be split down the middle
by the extension of County Fair Lane. The project is bounded on the north and west by
Harvest Park Subdivision, on the south by McClelland’s Channel, and on the east by
Ziegler Road.
1.2 Description of Property
The property consists of approximately 4.03 acres of land which will be separated into
two parcels by the County Fair Lane right-of-way. Both parcels are owned by the DP
Investment Group. The south parcel is considered the proposed development and is part
of the final compliance plans and the north parcel will be developed in the future. The
proposed development consists of approximately 2.71 acres and the future parcel to the
north consists of approximately 1.32 acres. The project will consist of four multifamily
building units and associated parking and drives. The land currently slopes to the south at
a range of approximately 1.5% to 2%. The land is currently occupied by one single
family home and several outbuildings. The majority of the ground cover is dryland
vegetation or gravel. There is offsite flow from the parcel to the north that presently
drains through the property. The offsite parcel consists of two single family homes,
several outbuildings and large gravel areas.
The McClelland’s Channel is located on the southerly portion of the site. McClelland’s
Channel was mapped by the City in November 2000 (revised in 2003) and there is a 100-
yr floodplain/floodway associated with the channel. The channel is not mapped by
FEMA. There are no proposed improvements within the City Floodplain/Floodway
boundary.
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2. DRAINAGE BASINS AND SUB-BASINS
2.1 Major Basin Description
The proposed development lies within the McClelland’s Creek Master Drainage Basin.
2.2 Sub-basin Description
The existing site drains to the south where it is intercepted by McClelland’s Channel.
The proposed development will increase the amount of flows that currently exists on site
due to an increase in impervious area. Because the time-to-peak of the onsite basins will
be much smaller than the time-to-peak of the overall McClelland Channel drainage basin
(see Section 3.3) and due to the sites’ close proximity to the river itself, the City of Fort
Collins Stormwater Department has determined that water quantity detention will not be
required. However, water quality treatment measures will be required for the developed
site.
Three off-site areas have been considered for this report. The first has been designated as
sub-basin OS-1 which includes the eastern half of the Ruff property which drains into
Ziegler Road. The Ruff property is located directly north of the proposed development.
Sub-basin OS-2 includes the Harvest Park Subdivision frontage along Ziegler Road up to
the existing high point in the road which is approximately 850’ north of the Lot 1
property line. OS-1 and OS-2 will sheet flow into the existing curb and gutter along the
west half of Ziegler Road and flow south until it is intercepted by the new street
intersection of County Fair Lane where the runoff will be collected in a Type R inlet and
routed through the site via storm pipe to the water quality pond.
Sub-basin OS-3 includes the Zeigler frontage just south of the proposed development that
drains to the north via curb and gutter where it is collected in a low point with a Type R
inlet. This runoff is conveyed via existing storm pipe directly to McClelland’s Channel
3
3. DRAINAGE DESIGN CRITERIA
3.1 Regulations
This report was prepared to meet or exceed the “City of Fort Collins Storm Drainage
Design Criteria Manual” specifications. Where applicable, the criteria established in the
“Urban Storm Drainage Criteria Manual” (UDFCD), developed by the Denver Regional
Council of Governments, has been used.
3.2 Directly Connected Impervious Area (DCIA) Discussion
Urban Drainage and Flood Control District (UDFCD) recommends a Four Step Process
for receiving water protection that focuses on reducing runoff volumes, treating the water
quality capture volume (WQCV), stabilizing drainageways and implementing long-term
source controls. The Four Step Process applies to the management of smaller, frequently
occurring events.
Step 1: Employ Runoff Reduction Practices
To reduce runoff peaks, volumes, and pollutant loads from urbanizing areas, implement
Low Impact Development (LID) strategies, including Minimizing Directly Connected
Impervious Areas (MDCIA). See the LID Area Exhibit in Appendix D.
Where space allows, runoff from this site will be routed through vegetated areas and into
a grass swale in order to slow runoff and promote infiltration during minor storm events.
Step 2: Implement BMPs that Provide a Water Quality Capture Volume with Slow
Release
Once runoff has been minimized, the remaining runoff shall be treated through capture
and slow release of the WQCV. The water quality pond located south of the site just
upstream from McClelland’s Channel will accomplish this requirement.
Step 3: Stabilize Drainageways
Natural Drainageways are subject to bed and bank erosion due to increases in frequency,
duration, rate and volume of runoff during and following development. The only
proposed improvement within a natural drainageway (McClelland’s Channel) is the water
quality pond spillway. This spillway will be stabilized with buried riprap. The outlet of
4
the water quality pond will be connected to an existing 24” pipe outfall that discharges
into the channel which is currently stabilized with riprap and vegetation.
Step 4: Implement Site Specific and Other Source Control BMPs
Proactively controlling pollutants at their source by preventing pollution rather than
removing contaminants once they have entered the stormwater system or receiving waters
is important when protecting storm systems and receiving waters. This can be
accomplished through site specific needs such as construction site runoff control, post-
construction runoff control and pollution prevention / good housekeeping. It will be the
responsibility of the contractor to develop a procedural best management practice for the
site.
3.3 Development Criteria Reference and Constraints
The runoff from this site has been routed to conform to the requirements of the City
Stormwater Department. Water quality facilities are required for the new construction
proposed on the site. Water quality will be met through the use of a grass swale and a
water quality pond. The City of Fort Collins has agreed that detention is not required for
this development because the peak flow coming off of the proposed site occurs well
before the peak flow in McClelland’s Channel. Specifically, the peak flow during the
100-yr storm event from the proposed site occurs at 35 minutes. According to the Master
Plan the peak flow just upstream of the proposed site in McClelland’s Channel occurs at
1 hour 11 minutes. Please refer to the proposed hydrograph in Appendix B.
3.4 Hydrologic Criteria
Runoff computations were prepared for the 2-year and 10-year minor and 100-year major
storm frequency utilizing the rational method. Colorado Urban Hydrograph Procedure
was used to generate the 100-year hydrograph for the site.
All hydrologic calculations associated with the basins are included in Appendix B of this
report. Standard Form 8 (SF-8) provides time of concentration calculations for all sub-
basins. Standard Form 9 (SF-9) provides a summary of the design flows for all Sub-
basins and Design Points associated with this site.
5
Water quality volume was calculated using the method recommended in the “Urban
Storm Drainage Criteria Manual”. All calculations are located in Appendix D.
3.5 Hydraulic Criteria
All final hydraulic calculations were prepared in accordance with the City of Fort Collins
Drainage Criteria and are included in Appendix C of this report.
The storm system has been designed to convey the 10-yr flow wherever there is overland
relief for the 100-year storm event. The 100-year flows will be conveyed overland
though the street, drive aisle and grass swale in such a way as to prevent flooding of
structures.
3.6 Floodplain Regulations Compliance
A completed “City of Fort Collins Floodplain Review Checklist for 100% Submittals”
has been included in Appendix E.
All floodway/floodplain information is in compliance with Chapter 10 of the City of Fort
Collins Municipal Code.
Although the McClelland’s Channel floodplain & floodway are within the limits of the
proposed development, no improvements are proposed within floodplain & floodway.
4. DRAINAGE FACILITY DESIGN
4.1 General Concept
The majority of the proposed development will be collected and conveyed to the
proposed water quality pond on the southern most portion of the site where it will be
treated before being released into McClelland’s Channel. The pond outfall will be
connected to an existing 24-inch storm pipe that discharges into McClelland’s Channel.
6
4.2 Specific Flow Routing
A summary of the drainage patterns within each basin is provided in the following
paragraphs.
Basin OS1 includes the area north of the proposed site that drains through the northern
parcel that will be part of a future development. This runoff will be cut off by the
extension of County Fair Lane and will be collected in the proposed catch basins and
conveyed to the proposed water quality pond. This basin also includes the frontage of the
existing portion of Ziegler Road. Runoff will follow existing flow patterns south along
Ziegler road where it will be intercepted by the proposed inlets in County Fair Lane.
Basin OS2 is a sub-basin from the Harvest Park Subdivision north of the site that drains
to the east where it is intercepted by the Ziegler Road curb and gutter and conveyed south
along Ziegler. This runoff will be intercepted by the proposed inlets at the low point in
County Fair Lane.
Basin 1 includes the northern half of the site, Lot 1, which is not part of this
development. Future development will consist of either additional multifamily homes
with associated drives or several commercial buildings with associated drives and parking
lot. While this basin remains undeveloped during the proposed development of the
southern parcel, runoff will follow existing flow patterns to the south where it will be
intercepted by County Fair Lane and captured in the proposed catch basins. Flow will
then be conveyed to the proposed water quality pond. Basin 1 also includes the northern
half of the County Fair Lane roadway improvements. Runoff from the northern half of
the roadway will be conveyed to the low point near the Zeigler intersection where it will
be collected by an inlet and piped to the water quality pond.
Basin 2 includes the existing Ziegler road frontage along the undeveloped northern
portion of the site. Ultimate improvements (to be completed with the future development
of the northern half) will include a detached sidewalk along Ziegler. All runoff follows
existing flow patterns south along the Ziegler curb and gutter until it is intercepted by the
proposed inlets in the low point of County Fair Lane. This runoff will be conveyed south
to the proposed water quality pond.
7
Basin 3 includes the northern half of the County Fair Lane improvements. Runoff will be
conveyed along the curb and gutter to a new low point where it will be collected in a
Type 5 inlet and conveyed via storm system #1 to the water quality pond.
Basin 4 includes the existing Ziegler road frontage that is adjacent to the southern half of
the site. Improvements will include a 6 foot detached sidewalk. Runoff will follow
existing flow patterns along the Ziegler curb and gutter to a low point just north of the
bridge that crosses McClelland’s Channel. Runoff is collected by an existing set of inlets
and then conveyed directly to an existing discharge location in McClelland’s Channel.
Runoff from Basin 4 is not conveyed to the proposed water quality pond. The proposed
pond is treating approximately 510 LF of existing Ziegler Road frontage that is included
in Basin OS1. Basin 4 consists of approximately 498 LF of existing Ziegler Road
frontage that will not be treated in the proposed pond. The City has agreed that it is
acceptable to not treat Basin 4 and trade that water with the runoff from the Ziegler
frontage in Basin OS1.
Basin 6 includes the County Fair Lane improvements that are east of the proposed high
point (approximately 40 LF). Runoff will be conveyed along the curb and gutter to an
existing low point in County Fair Lane approximately 120 feet west of the property line.
This runoff is conveyed to the Harvest Park Pond. This area was accounted for in the
original Harvest Park Drainage Report.
Basin 7 includes the western half of the roof of Building A. Roof runoff will be collected
and hard piped to a private storm system which will convey the runoff to storm system #1
which drains into the water quality pond.
Basin 8 includes the eastern half of the roof of Building A. Roof runoff will be collected
and hard piped to storm system #1 which drains into the water quality pond.
Basin 9 includes the western half of the roof of Building D. Roof runoff will be collected
and hard piped to storm system #1 which drains into the water quality pond.
Basin 10 includes the open space between buildings A and B. Runoff will sheet flow to a
proposed lowpoint where it will be collected with an area drain and conveyed to storm
system #1 which drains into the water quality pond.
8
Basin 11 includes the western half of the roof of Building B. Roof runoff will be
collected and hard piped to a private storm system which will convey the runoff to storm
system #1 which drains into the water quality pond.
Basin 12 includes the eastern half of the roof of Building B. Roof runoff will be
collected and hard piped to storm system #1 which drains into the water quality pond.
Basin 13 includes the parking lot between Building C and D. Runoff will sheet flow over
the pavement until it is intercepted by the curb and gutter and conveyed to a lowpoint in
the southeast corner of the lot. A Type R inlet will collect the runoff and a private storm
system will convey the runoff to storm system #1 which drains into the water quality
pond.
Basin 14 includes the western half of the roof of Building C. Roof runoff will be
collected and hard piped to storm system #1 which drains into the water quality pond.
Basin 15 includes the concrete drive that provides access to all buildings on site. The
drive is an inverted crown and all runoff will be conveyed to south where it will discharge
directly into the water quality pond.
Basin 16 includes the eastern half of the roof of Building C and D as well as the
landscape area between the Ziegler right-of-way and the Building C and D. Runoff will
be conveyed to a grass swale which will encourage infiltration. Due to the poor on site
soils, the swale will have an underdrain system to eliminate standing water. Access
runoff in the swale will be collected with an area inlet and connected to an existing 24”
storm sewer pipe that discharges directly to McClelland’s Channel.
Basin 17 includes the walk and landscape area west of Building A that cannot be
collected and conveyed to storm system #1 due to site constraints. Runoff from this basin
sheet flows into the Harvest Park detention pond directly west of the site.
Basin 18 includes the walk and landscape area west of Building B that cannot be
collected and conveyed to storm system #1 due to site constraints. Runoff from this basin
sheet flows into the Harvest Park detention pond directly west of the site.
9
4.3 Drainage Summary
Drainage facilities located outside of the right of way (including the grass swale, water
quality pond, proposed storm drain system and the pond outlet) will be maintained by the
owners of the property.
5. CONCLUSIONS
5.1 Compliance with Standards
All computations that have been completed within this report are in compliance with the
City of Fort Collins Erosion Control Reference Manual for Construction Sites and the
Storm Drainage Design Criteria Manual. All floodway information is in compliance with
Chapter 10 of the City of Fort Collins Municipal Code.
5.2 Drainage Concept
The proposed drainage concepts presented in this report and on the construction plans
adequately provide for stormwater quality treatment of proposed impervious areas.
Conveyance elements have been designed to pass required flows and to minimize future
maintenance.
If, at the time of construction, groundwater is encountered, a Colorado Department of
Health Construction Dewatering Permit will be required.
10
6. REFERENCES
1. City of Fort Collins, “Storm Drainage Criteria Manual”, (SDCM), dated March,
1986.
2. Urban Drainage and Flood Control District, “Urban Storm Drainage Criteria
Manual”, Volumes 1 and 2, dated June 2001, and Volume 3 dated September
1999.
3. ICON Engineering, Inc., “McClelland’s Creek Master Drainage Plan Update”,
dated November 20, 2000 (Revised March 2003).
A
APPENDIX A
VICINITY MAP AND DRAINAGE PLAN
B
APPENDIX B
HYDROLOGIC COMPUTATIONS
SUMMARY
DRAINAGE SUMMARY TABLE
Design Tributary Area C (2) C (10) C (100) tc (2) tc (10) tc (100) Q(2)tot Q(10)tot Q(100)tot DRAINAGE
Sub-basin STRUCTURE
Point (ac) (min) (min) (min) (cfs) (cfs) (cfs) /REMARKS
OS-1 2.05 0.50 0.50 0.62 13.9 13.9 12.7 2.0 3.4 9.0
OS-2 0.41 0.65 0.65 0.81 7.1 7.1 5.3 0.7 1.2 3.2
OS-3 0.19 0.79 0.79 0.99 5.0 5.0 5.0 0.4 0.7 1.9
1 0.98 0.74 0.74 0.93 5.9 5.9 5.0 2.0 3.3 9.1
2 0.20 0.81 0.81 1.00 5.0 5.0 5.0 0.5 0.8 2.0
3 0.12 0.84 0.84 1.00 5.0 5.0 5.0 0.3 0.5 1.1
4 0.47 0.80 0.80 1.00 5.0 5.0 5.0 1.1 1.9 4.7
5 0.19 0.65 0.65 0.81 5.0 5.0 5.0 0.3 0.6 1.5
6 0.06 0.79 0.79 0.98 5.0 5.0 5.0 0.1 0.2 0.6
7 0.07 0.95 0.95 1.00 5.0 5.0 5.0 0.2 0.3 0.7
8 0.08 0.95 0.95 1.00 5.0 5.0 5.0 0.2 0.4 0.8
9 0.07 0.95 0.95 1.00 5.0 5.0 5.0 0.2 0.3 0.7
10 0.10 0.46 0.46 0.57 5.0 5.0 5.0 0.1 0.2 0.6
11 0.07 0.95 0.95 1.00 5.0 5.0 5.0 0.2 0.3 0.7
12 0.08 0.95 0.95 1.00 5.0 5.0 5.0 0.2 0.4 0.8
13 0.12 0.84 0.84 1.00 5.0 5.0 5.0 0.3 0.5 1.2
14 0.07 0.95 0.95 1.00 5.0 5.0 5.0 0.2 0.3 0.7
15 0.59 0.56 0.56 0.70 6.6 6.6 5.8 0.8 1.4 3.9
16 0.31 0.53 0.53 0.66 6.0 6.0 5.6 0.4 0.7 1.9
17 0.05 0.40 0.40 0.50 5.0 5.0 5.0 0.1 0.1 0.3
18 0.04 0.38 0.38 0.48 5.1 5.1 5.0 0.0 0.1 0.2
19 0.37 0.20 0.20 0.25 7.5 7.5 7.4 0.2 0.3 0.8
OVERALL SITE 4.03 0.67 0.67 0.84 14.3 14.3 10.8 5.2 8.8 25.4
Page 7
Interwest Consulting Group
1218 West Ash, Suite C
Windsor, Colorado
LOCATION: ZIEGLER MIXED USE
PROJECT NO: 1154-095-00
COMPUTATIONS BY: SB
DATE: 9/4/2014
Recommended Runoff Coefficients from Table 3-3 of City of Fort Collins Design Criteria
Recommended % Impervious from Urban Storm Drainage Criteria Manual
Runoff %
coefficient Impervious
C
Streets, parking lots (asphalt): 0.95 100
Concrete: 0.95 96
Roofs: 0.95 90
Gravel: 0.50 40
Lawns (flat <2%, heavy soil): 0.20 0
SUBBASIN TOTAL TOTAL PAVED CONCRETE ROOF GRAVEL LANDSCAPE RUNOFF %
DESIGNATION AREA AREA AREA AREA AREA AREA AREA COEFF. Impervious REMARKS
(ac.) (sq.ft) (sq.ft) (sq.ft) (sq.ft) (sq.ft) (sq.ft) (C)
OS-1 2.05 89,485 13,234 0 6,612 39,400 30,239 0.50 39 OFF SITE NORTH
OS-2 0.41 18,000 8,736 2,015 0 0 7,249 0.65 59 OFF SITE NORTH, ZIEGLER FRONTAGE
OS-3 0.19 8,420 5,630 1,040 0 0 1,750 0.79 79 OFF SITE SOUTH, ZIEGLER FRONTAGE
1 0.98 42,666 0 18,000 13,000 0 11,666 0.74 68 NORTH PARCEL
2 0.20 8,649 5,822 1,182 0 0 1,645 0.81 80 NORTH PARCEL, ZIEGLER FRONTAGE
3 0.12 5,010 0 4,303 0 0 707 0.84 82
4 0.47 20,654 13,285 3,372 0 0 3,997 0.80 80
5 0.19 8,234 0 4,923 0 0 3,311 0.65 57
6 0.06 2,664 0 2,085 0 0 579 0.79 75
7 0.07 2,949 0 0 2,949 0 0 0.95 90
8 0.08 3,493 0 0 3,493 0 0 0.95 90
9 0.07 2,927 0 0 2,927 0 0 0.95 90
10 0.10 4,560 0 1,551 0 0 3,009 0.46 33
11 0.07 2,949 0 0 2,949 0 0 0.95 90
12 0.08 3,492 0 0 3,492 0 0 0.95 90
13 0.12 5,153 0 4,400 0 0 753 0.84 82
14 0.07 2,927 0 0 2,927 0 0 0.95 90
15 0.59 25,530 0 12,330 0 0 13,200 0.56 46
16 0.31 13,449 0 1,244 4,604 0 7,601 0.53 40
17 0.05 2,323 0 617 0 0 1,706 0.40 25
18 0.04 1,684 0 411 0 0 1,273 0.38 23
19 0.37 16,232 0 0 0 0 16,232 0.20 0
OVERALL SITE 4.03 175,545 19,107 54,418 36,341 0 65,679 0.67 59 OVERALL SITE
Equations
- Calculated C coefficients & % Impervious are area weighted
C = Σ (Ci Ai) / At
Ci = runoff coefficient for specific area, Ai
Ai = areas of surface with runoff coefficient of Ci
n = number of different surfaces to consider
At = total area over which C is applicable; the sum of all Ai's
RUNOFF COEFFICIENTS & % IMPERVIOUS
Flow-FINAL.xls Cval
Interwest Consulting Group
1218 West Ash, Suite C
Windsor, Colorado
LOCATION: ZIEGLER MIXED USE
PROJECT NO: 1154-095-00
COMPUTATIONS BY: SB
DATE: 9/4/2014
10-yr storm Cf = 1.00
SUB-BASIN INITIAL /OVERLAND TRAVEL TIME / GUTTER OR CHANNEL FLOW tc CHECK FINAL REMARKS
DATA TIME (ti) (tt) (URBANIZED BASIN) tc
DESIGN SUBBASIN(s) Area C Length Slope ti Length Slope n Vel. tt tc = Total L tc=(l/180)+10
POINT (ac) (ft) (%) (min) (ft) (%) Manning (ft/s) (min) ti + tt (ft) (min) (min)
(1) (2) (3) (4) (5) (6) (7) (8) rough. (9) (10) (11) (12) (13) (14)
OS-1 2.05 0.50 215 2.0 12.6 495 2.30 0.016 3.0 2.7 15.3 710 13.9 13.9
OS-2 0.41 0.65 55 2.0 4.8 335 1.50 0.016 2.5 2.3 7.1 390 12.2 7.1
OS-3 0.19 0.79 24 2.0 2.1 195 1.50 0.016 2.5 1.3 3.5 219 11.2 5.0
1 0.98 0.74 45 2.0 3.4 295 1.00 0.016 2.0 2.4 5.9 340 11.9 5.9
2 0.20 0.81 16 2.0 1.7 205 2.30 0.016 3.0 1.1 2.8 221 11.2 5.0
3 0.12 0.84 16 2.0 1.5 120 0.80 0.016 1.8 1.1 2.6 136 10.8 5.0
4 0.47 0.80 16 2.0 1.7 270 2.30 0.016 3.0 1.5 3.2 286 11.6 5.0
5 0.19 0.65 26 2.0 3.3 125 0.80 0.016 1.8 1.2 4.4 151 10.8 5.0
6 0.06 0.79 10 2.0 1.4 50 0.50 0.016 1.4 0.6 2.0 60 10.3 5.0
7 0.07 0.95 35 100.0 0.3 30 1.00 0.012 2.7 0.2 0.5 65 10.4 5.0
8 0.08 0.95 35 100.0 0.3 30 1.00 0.012 2.7 0.2 0.5 65 10.4 5.0
9 0.07 0.95 35 100.0 0.3 30 1.00 0.012 2.7 0.2 0.5 65 10.4 5.0
10 0.10 0.46 40 5.0 4.3 40 0.50 0.012 1.9 0.4 4.6 80 10.4 5.0
11 0.07 0.95 35 100.0 0.3 30 1.00 0.012 2.7 0.2 0.5 65 10.4 5.0
12 0.08 0.95 35 100.0 0.3 30 1.00 0.012 2.7 0.2 0.5 65 10.4 5.0
13 0.12 0.84 70 4.0 2.5 6 3.00 0.016 3.5 0.0 2.5 76 10.4 5.0
14 0.07 0.95 35 100.0 0.3 30 1.00 0.012 2.7 0.2 0.5 65 10.4 5.0
15 0.59 0.56 12 1.0 3.4 281 0.50 0.016 1.4 3.3 6.6 293 11.6 6.6
16 0.31 0.53 24 25.0 1.7 240 1.00 0.034 0.9 4.2 6.0 264 11.5 6.0
17 0.05 0.40 25 2.0 5.0 0 0.00 0.000 0.0 0.0 5.0 25 10.1 5.0
18 0.04 0.38 25 2.0 5.1 0 0.00 0.000 0.0 0.0 5.1 25 10.1 5.1
19 0.37 0.20 18 50.0 1.9 218 0.50 0.035 0.6 5.6 7.5 236 11.3 7.5
OVERALL SITE 4.03 0.67 240 2.0 9.5 525 0.50 0.013 1.7 5.0 14.5 765 14.3 14.3
EQUATIONS:
tc = ti + tt
ti = [1.87 (1.1 - CCf ) L0.5 ] / S 1/3
tt = L/Vel.
Velocity from Manning's Equation with R=0.1 (corresponds to Figure 3-3 of City of Fort Collins Design Manual)
final tc = minimum of ti + tt and urbanized basin check
min. tc = 5 min. due to limits of IDF curves
STANDARD FORM SF-2
TIME OF CONCENTRATION - 10 YEAR
Flow-FINAL.xls TOC-10
Interwest Consulting Group
1218 West Ash, Suite C
Windsor, Colorado
LOCATION: ZIEGLER MIXED USE
PROJECT NO: 1154-095-00
COMPUTATIONS BY: SB
DATE: 9/4/2014
100-yr storm Cf = 1.25
SUB-BASIN INITIAL /OVERLAND TRAVEL TIME / GUTTER OR CHANNEL FLOW tc CHECK FINAL REMARKS
DATA TIME (ti) (tt) (URBANIZED BASIN) tc
DESIGN SUBBASIN(s) Area C C*Cf Length Slope ti Length Slope n Vel. tt tc = Total L tc=(l/180)+10
POINT (ac) (ft) (%) (min) (ft) (%) Manning (ft/s) (min) ti + tt (ft) (min) (min)
(1) (2) (3) (4) (5) (6) (7) (8) rough. (9) (10) (11) (12) (13) (14)
OS-1 2.05 0.50 0.62 215 2.0 10.0 495 2.30 0.016 3.0 2.7 12.7 710 13.9 12.7
OS-2 0.41 0.65 0.81 55 2.0 3.1 335 1.50 0.016 2.5 2.3 5.3 390 12.2 5.3
OS-3 0.19 0.79 0.99 24 2.0 0.8 195 1.50 0.016 2.5 1.3 2.1 219 11.2 5.0
1 0.98 0.74 0.93 45 2.0 1.6 295 1.00 0.016 2.0 2.4 4.1 340 11.9 5.0
2 0.20 0.81 1.00 16 2.0 0.6 205 2.30 0.016 3.0 1.1 1.7 221 11.2 5.0
3 0.12 0.84 1.00 16 2.0 0.6 120 0.80 0.016 1.8 1.1 1.7 136 10.8 5.0
4 0.47 0.80 1.00 16 2.0 0.6 270 2.30 0.016 3.0 1.5 2.0 286 11.6 5.0
5 0.19 0.65 0.81 26 2.0 2.1 125 0.80 0.016 1.8 1.2 3.3 151 10.8 5.0
6 0.06 0.79 0.98 10 2.0 0.5 50 0.50 0.016 1.4 0.6 1.1 60 10.3 5.0
7 0.07 0.95 1.00 35 100.0 0.2 30 1.00 0.012 2.7 0.2 0.4 65 10.4 5.0
8 0.08 0.95 1.00 35 100.0 0.2 30 1.00 0.012 2.7 0.2 0.4 65 10.4 5.0
9 0.07 0.95 1.00 35 100.0 0.2 30 1.00 0.012 2.7 0.2 0.4 65 10.4 5.0
10 0.10 0.46 0.57 40 5.0 3.5 40 0.50 0.012 1.9 0.4 3.9 80 10.4 5.0
11 0.07 0.95 1.00 35 100.0 0.2 30 1.00 0.012 2.7 0.2 0.4 65 10.4 5.0
12 0.08 0.95 1.00 35 100.0 0.2 30 1.00 0.012 2.7 0.2 0.4 65 10.4 5.0
13 0.12 0.84 1.00 70 4.0 0.9 6 3.00 0.016 3.5 0.0 1.0 76 10.4 5.0
14 0.07 0.95 1.00 35 100.0 0.2 30 1.00 0.012 2.7 0.2 0.4 65 10.4 5.0
15 0.59 0.56 0.70 12 1.0 2.5 281 0.50 0.016 1.4 3.3 5.8 293 11.6 5.8
16 0.31 0.53 0.66 24 25.0 1.3 240 1.00 0.034 0.9 4.2 5.6 264 11.5 5.6
17 0.05 0.40 0.50 25 2.0 4.3 0 0.00 0.000 0.0 0.0 4.3 25 10.1 5.0
18 0.04 0.38 0.48 25 2.0 4.4 0 0.00 0.000 0.0 0.0 4.4 25 10.1 5.0
19 0.37 0.20 0.25 18 50.0 1.8 218 0.50 0.035 0.6 5.6 7.4 236 11.3 7.4
OVERALL SITE 4.03 0.67 0.84 240 2.0 5.8 525 0.50 0.013 1.7 5.0 10.8 765 14.3 10.8
EQUATIONS:
tc = ti + tt
ti = [1.87 (1.1 - CCf ) L0.5 ] / S 1/3
tt = L/Vel.
Velocity from Manning's Equation with R=0.1 (corresponds to Figure 3-3 of City of Fort Collins Design Manual)
final tc = minimum of ti + tt and urbanized basin check
min. tc = 5 min. due to limits of IDF curves
TIME OF CONCENTRATION - 100 YR
STANDARD FORM SF-2
Flow-FINAL.xls TOC-100
Interwest Consulting Group
1218 West Ash, Suite C
Windsor, Colorado
RATIONAL METHOD PEAK RUNOFF
(2-YEAR)
LOCATION: ZIEGLER MIXED USE
PROJECT NO: 1154-095-00
COMPUTATIONS BY: SB
DATE: 9/4/2014
2-yr storm, Cf = 1.00
DIRECT RUNOFF CARRY OVER TOTAL REMARKS
Design Tributary A C Cf tc i Q (2) from Q (2) Q(2)tot
Sub-basin (new) Design
Point (ac) (min) (in/hr) (cfs) Point (cfs) (cfs)
OS-1 2.05 0.50 13.9 1.93 2.0
OS-2 0.41 0.65 7.1 2.53 0.7
OS-3 0.19 0.79 5.0 2.85 0.4
1 0.98 0.74 5.9 2.68 2.0
2 0.20 0.81 5.0 2.85 0.5
3 0.12 0.84 5.0 2.85 0.3
4 0.47 0.80 5.0 2.85 1.1
5 0.19 0.65 5.0 2.85 0.3
6 0.06 0.79 5.0 2.85 0.1
7 0.07 0.95 5.0 2.85 0.2
8 0.08 0.95 5.0 2.85 0.2
9 0.07 0.95 5.0 2.85 0.2
10 0.10 0.46 5.0 2.85 0.1
11 0.07 0.95 5.0 2.85 0.2
12 0.08 0.95 5.0 2.85 0.2
13 0.12 0.84 5.0 2.85 0.3
14 0.07 0.95 5.0 2.85 0.2
15 0.59 0.56 6.6 2.58 0.8
16 0.31 0.53 6.0 2.66 0.4
17 0.05 0.40 5.0 2.80 0.1
18 0.04 0.38 5.1 2.78 0.0
19 0.37 0.20 7.5 2.48 0.2
OVERALL SITE 4.03 0.67 14.3 1.91 5.2
Q = Cf C iA
Q = peak discharge (cfs)
C = runoff coefficient
Cf = frequency adjustment factor
I = rainfall intensity (in/hr) from IDF curve
A = drainage area (acres)
NOTE: Intensity based on Figure 3-1, 1999 (Regional Analysis)
Flow-FINAL.xls Q2
Interwest Consulting Group
1218 West Ash, Suite C
Windsor, Colorado
RATIONAL METHOD PEAK RUNOFF
(10-YEAR)
LOCATION: ZIEGLER MIXED USE
PROJECT NO: 1154-095-00
COMPUTATIONS BY: SB
DATE: 9/4/2014
10-yr storm, Cf = 1.00
DIRECT RUNOFF CARRY OVER TOTAL REMARKS
Design Tributary A C Cf tc i Q (10) from Q (10) Q(10)tot
Sub-basin (new) Design
Point (ac) (min) (in/hr) (cfs) Point (cfs) (cfs)
OS-1 2.05 0.50 13.9 3.29 3.4 3.4
OS-2 0.41 0.65 7.1 4.32 1.2 1.2
OS-3 0.19 0.79 5.0 4.87 0.7 0.7
1 0.98 0.74 5.9 4.58 3.3 3.3
2 0.20 0.81 5.0 4.87 0.8 0.8
3 0.12 0.84 5.0 4.87 0.5 0.5
4 0.47 0.80 5.0 4.87 1.9 1.9
5 0.19 0.65 5.0 4.87 0.6 0.6
6 0.06 0.79 5.0 4.87 0.2 0.2
7 0.07 0.95 5.0 4.87 0.3 0.3
8 0.08 0.95 5.0 4.87 0.4 0.4
9 0.07 0.95 5.0 4.87 0.3 0.3
10 0.10 0.46 5.0 4.87 0.2 0.2
11 0.07 0.95 5.0 4.87 0.3 0.3
12 0.08 0.95 5.0 4.87 0.4 0.4
13 0.12 0.84 5.0 4.87 0.5 0.5
14 0.07 0.95 5.0 4.87 0.3 0.3
15 0.59 0.56 6.6 4.40 1.4 1.4
16 0.31 0.53 6.0 4.55 0.7 0.7
17 0.05 0.40 5.0 4.78 0.1 0.1
18 0.04 0.38 5.1 4.75 0.1 0.1
19 0.37 0.20 7.5 4.24 0.3 0.3
OVERALL SITE 4.03 0.67 14.3 3.26 8.8 8.8
Q = Cf C iA
Q = peak discharge (cfs)
C = runoff coefficient
Cf = frequency adjustment factor
I = rainfall intensity (in/hr) from IDF curve
A = drainage area (acres)
NOTE: Intensity based on Figure 3-1, 1999 (Regional Analysis)
Flow-FINAL.xls Q10
Interwest Consulting Group
1218 West Ash, Suite C
Windsor, Colorado
RATIONAL METHOD PEAK RUNOFF
(100-YEAR)
LOCATION: ZIEGLER MIXED USE
PROJECT NO: 1154-095-00
COMPUTATIONS BY: SB
DATE: 9/4/2014
100-yr storm, Cf = 1.25
DIRECT RUNOFF CARRY OVER TOTAL REMARKS
Des. Area A C Cf tc i Q (100) from Q (100) Q(100)tot
(new) Design
Point Design. (ac) (min) (in/hr) (cfs) Point (cfs) (cfs)
OS-1 2.05 0.62 12.7 7.02 9.0 9.0
OS-2 0.41 0.81 5.3 9.59 3.2 3.2
OS-3 0.19 0.99 5.0 9.95 1.9 1.9
1 0.98 0.93 5.0 9.95 9.1 9.1
2 0.20 1.00 5.0 9.95 2.0 2.0
3 0.12 1.00 5.0 9.95 1.1 1.1
4 0.47 1.00 5.0 9.95 4.7 4.7
5 0.19 0.81 5.0 9.95 1.5 1.5
6 0.06 0.98 5.0 9.95 0.6 0.6
7 0.07 1.00 5.0 9.95 0.7 0.7
8 0.08 1.00 5.0 9.95 0.8 0.8
9 0.07 1.00 5.0 9.95 0.7 0.7
10 0.10 0.57 5.0 9.95 0.6 0.6
11 0.07 1.00 5.0 9.95 0.7 0.7
12 0.08 1.00 5.0 9.95 0.8 0.8
13 0.12 1.00 5.0 9.95 1.2 1.2
14 0.07 1.00 5.0 9.95 0.7 0.7
15 0.59 0.70 5.8 9.39 3.9 3.9
16 0.31 0.66 5.6 9.49 1.9 1.9
17 0.05 0.50 5.0 9.95 0.3 0.3
18 0.04 0.48 5.0 9.95 0.2 0.2
19 0.37 0.25 7.4 8.70 0.8 0.8
OVERALL SITE 4.03 0.84 10.8 7.52 25.4 25.4
Q = C iA
Q = peak discharge (cfs)
C = runoff coefficient
I = rainfall intensity (in/hr) from IDF curve
A = drainage area (acres)
NOTE: Intensity based on Figure 3-1, 1999 (Regional Analysis)
Flow-FINAL.xls Q100
C
APPENDIX C
HYDRAULIC CALCULATIONS
Worksheet Protected
Project:
Inlet ID:
Design Flow: ONLY if already determined through other methods: Minor Storm Major Storm
(local peak flow for 1/2 of street OR grass-lined channel): *QKnown = 5.9 15.3 cfs
* If you enter values in Row 14, skip the rest of this sheet and proceed to sheet Q-Allow or Area Inlet.
Geographic Information: (Enter data in the blue cells):
Subcatchment Area = Acres
Percent Imperviousness = %
NRCS Soil Type = A, B, C, or D
Slope (ft/ft) Length (ft)
Overland Flow =
Channel Flow =
Rainfall Information: Intensity I (inch/hr) = C1
* P1
/ ( C2
+ Tc
) ^ C3 Minor Storm Major Storm
Design Storm Return Period, Tr
= years
Return Period One-Hour Precipitation, P1
= inches
C1
=
C2
=
C3
=
User-Defined Storm Runoff Coefficient (leave this blank to accept a calculated value), C =
User-Defined 5-yr. Runoff Coefficient (leave this blank to accept a calculated value), C5
=
Bypass (Carry-Over) Flow from upstream Subcatchments, Qb
= 0.00 0.00 cfs
Total Design Peak Flow, Q = 5.9 15.3 cfs
<---
FILL IN THIS SECTION
OR…
FILL IN THE
SECTIONS BELOW.
<---
DESIGN PEAK FLOW FOR ONE-HALF OF STREET
OR GRASS-LINED CHANNEL BY THE RATIONAL METHOD
Harvest Park - Ziegler Mixed Use
A1
Site is Urban
Site is Non-Urban
Show Details
Site Type:
Street Inlets
Area Inlets in a Median
Flows Developed For:
Inlet A-1 (5 FT TYPE R).xlsm, Q-Peak 9/10/2014, 8:01 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 nBACK = 0.016
Height of Curb at Gutter Flow Line HCURB = 6.00 inches
Distance from Curb Face to Street Crown TCROWN = 18.0 ft
Gutter Width W = 2.00 ft
Street Transverse Slope SX = 0.020 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 nSTREET = 0.016
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX = 12.0 18.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no) check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow = SUMP SUMP cfs
Major storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak'
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
Harvest Park - Ziegler Mixed Use
A1
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Minor storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak'
Inlet A-1 (5 FT TYPE R).xlsm, Q-Allow 9/10/2014, 8:01 AM
Project =
Inlet ID =
Design Information (Input) MINOR MAJOR
Type of Inlet Inlet Type =
Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal
= 3.00 3.00 inches
Number of Unit Inlets (Grate or Curb Opening) No = 1 1
Water Depth at Flowline (outside of local depression) Ponding Depth = 6.0 8.8 inches
Grate Information MINOR MAJOR
Length of a Unit Grate Lo
(G) = N/A N/A feet
Width of a Unit Grate Wo
= N/A N/A feet
Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio
= N/A N/A
Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf
(G) = N/A N/A
Grate Weir Coefficient (typical value 2.15 - 3.60) Cw
(G) = N/A N/A
Grate Orifice Coefficient (typical value 0.60 - 0.80) Co
(G) = N/A N/A
Curb Opening Information MINOR MAJOR
Length of a Unit Curb Opening Lo
(C) = 5.00 5.00 feet
Height of Vertical Curb Opening in Inches Hvert
= 6.00 6.00 inches
Height of Curb Orifice Throat in Inches Hthroat
= 6.00 6.00 inches
Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 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 2.3-3.6) Cw
(C) = 3.60 3.60
Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co
(C) = 0.67 0.67
MINOR MAJOR
Total Inlet Interception Capacity (assumes clogged condition) Q
a = 5.4 10.4 cfs
WARNING: Inlet Capacity less than Q Peak for Minor and Major Storms Q
PEAK REQUIRED = 5.9 15.3 cfs
INLET IN A SUMP OR SAG LOCATION
Harvest Park - Ziegler Mixed Use
A1
CDOT Type R Curb Opening
H-Vert
H-Curb
W
Lo (C)
Lo (G)
Wo
WP
Inlet A-1 (5 FT TYPE R).xlsm, Inlet In Sump 9/10/2014, 8:01 AM
Worksheet Protected
Project:
Inlet ID:
Design Flow: ONLY if already determined through other methods: Minor Storm Major Storm
(local peak flow for 1/2 of street OR grass-lined channel): *QKnown = 0.6 1.5 cfs
* If you enter values in Row 14, skip the rest of this sheet and proceed to sheet Q-Allow or Area Inlet.
Geographic Information: (Enter data in the blue cells):
Subcatchment Area = Acres
Percent Imperviousness = %
NRCS Soil Type = A, B, C, or D
Slope (ft/ft) Length (ft)
Overland Flow =
Channel Flow =
Rainfall Information: Intensity I (inch/hr) = C1
* P1
/ ( C2
+ Tc
) ^ C3 Minor Storm Major Storm
Design Storm Return Period, Tr
= years
Return Period One-Hour Precipitation, P1
= inches
C1
=
C2
=
C3
=
User-Defined Storm Runoff Coefficient (leave this blank to accept a calculated value), C =
User-Defined 5-yr. Runoff Coefficient (leave this blank to accept a calculated value), C5
=
Bypass (Carry-Over) Flow from upstream Subcatchments, Qb
= 0.50 4.90 cfs
Total Design Peak Flow, Q = 1.1 6.4 cfs
<---
FILL IN THIS SECTION
OR…
FILL IN THE
SECTIONS BELOW.
<---
DESIGN PEAK FLOW FOR ONE-HALF OF STREET
OR GRASS-LINED CHANNEL BY THE RATIONAL METHOD
Harvest Park - Ziegler Mixed Use
A2
Site is Urban
Site is Non-Urban
Show Details
Site Type:
Street Inlets
Area Inlets in a Median
Flows Developed For:
Inlet A-2 (5 FT TYPE R).xlsm, Q-Peak 9/10/2014, 8:05 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 nBACK = 0.016
Height of Curb at Gutter Flow Line HCURB = 6.00 inches
Distance from Curb Face to Street Crown TCROWN = 18.0 ft
Gutter Width W = 2.00 ft
Street Transverse Slope SX = 0.020 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 nSTREET = 0.016
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX = 12.0 18.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no) check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow = SUMP SUMP cfs
Major storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak'
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
Harvest Park - Ziegler Mixed Use
A2
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Minor storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak'
Inlet A-2 (5 FT TYPE R).xlsm, Q-Allow 9/10/2014, 8:05 AM
Project =
Inlet ID =
Design Information (Input) MINOR MAJOR
Type of Inlet Inlet Type =
Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal
= 3.00 3.00 inches
Number of Unit Inlets (Grate or Curb Opening) No = 1 1
Water Depth at Flowline (outside of local depression) Ponding Depth = 6.0 8.8 inches
Grate Information MINOR MAJOR
Length of a Unit Grate Lo
(G) = N/A N/A feet
Width of a Unit Grate Wo
= N/A N/A feet
Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio
= N/A N/A
Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf
(G) = N/A N/A
Grate Weir Coefficient (typical value 2.15 - 3.60) Cw
(G) = N/A N/A
Grate Orifice Coefficient (typical value 0.60 - 0.80) Co
(G) = N/A N/A
Curb Opening Information MINOR MAJOR
Length of a Unit Curb Opening Lo
(C) = 5.00 5.00 feet
Height of Vertical Curb Opening in Inches Hvert
= 6.00 6.00 inches
Height of Curb Orifice Throat in Inches Hthroat
= 6.00 6.00 inches
Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 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 2.3-3.6) Cw
(C) = 3.60 3.60
Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co
(C) = 0.67 0.67
MINOR MAJOR
Total Inlet Interception Capacity (assumes clogged condition) Q
a = 5.4 10.4 cfs
Inlet Capacity IS GOOD for Minor and Major Storms (>Q PEAK) Q
PEAK REQUIRED = 1.1 6.4 cfs
INLET IN A SUMP OR SAG LOCATION
Harvest Park - Ziegler Mixed Use
A2
CDOT Type R Curb Opening
H-Vert
H-Curb
W
Lo (C)
Lo (G)
Wo
WP
Inlet A-2 (5 FT TYPE R).xlsm, Inlet In Sump 9/10/2014, 8:05 AM
Worksheet Protected
Project:
Inlet ID:
Design Flow: ONLY if already determined through other methods: Minor Storm Major Storm
(local peak flow for 1/2 of street OR grass-lined channel): *QKnown = 0.5 1.2 cfs
* If you enter values in Row 14, skip the rest of this sheet and proceed to sheet Q-Allow or Area Inlet.
Geographic Information: (Enter data in the blue cells):
Subcatchment Area = Acres
Percent Imperviousness = %
NRCS Soil Type = A, B, C, or D
Slope (ft/ft) Length (ft)
Overland Flow =
Channel Flow =
Rainfall Information: Intensity I (inch/hr) = C1
* P1
/ ( C2
+ Tc
) ^ C3 Minor Storm Major Storm
Design Storm Return Period, Tr
= years
Return Period One-Hour Precipitation, P1
= inches
C1
=
C2
=
C3
=
User-Defined Storm Runoff Coefficient (leave this blank to accept a calculated value), C =
User-Defined 5-yr. Runoff Coefficient (leave this blank to accept a calculated value), C5
=
Bypass (Carry-Over) Flow from upstream Subcatchments, Qb
= 0.00 0.00 cfs
Total Design Peak Flow, Q = 0.5 1.2 cfs
<---
FILL IN THIS SECTION
OR…
FILL IN THE
SECTIONS BELOW.
<---
DESIGN PEAK FLOW FOR ONE-HALF OF STREET
OR GRASS-LINED CHANNEL BY THE RATIONAL METHOD
Harvest Park - Ziegler Mixed Use
A3
Site is Urban
Site is Non-Urban
Show Details
Site Type:
Street Inlets
Area Inlets in a Median
Flows Developed For:
Inlet A-3 (5 FT TYPE R) - Copy.xlsm, Q-Peak 9/10/2014, 8:03 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 nBACK = 0.016
Height of Curb at Gutter Flow Line HCURB = 6.00 inches
Distance from Curb Face to Street Crown TCROWN = 18.0 ft
Gutter Width W = 2.00 ft
Street Transverse Slope SX = 0.020 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 nSTREET = 0.016
Minor Storm Major Storm
Max. Allowable Spread for Minor & Major Storm TMAX = 12.0 18.0 ft
Max. Allowable Depth at Gutter Flowline for Minor & Major Storm dMAX = 6.0 6.0 inches
Allow Flow Depth at Street Crown (leave blank for no) check = yes
MINOR STORM Allowable Capacity is based on Depth Criterion Minor Storm Major Storm
MAJOR STORM Allowable Capacity is based on Depth Criterion Qallow = SUMP SUMP cfs
Major storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak'
ALLOWABLE CAPACITY FOR ONE-HALF OF STREET (Minor & Major Storm)
Harvest Park - Ziegler Mixed Use
A3
(Based on Regulated Criteria for Maximum Allowable Flow Depth and Spread)
Minor storm max. allowable capacity GOOD - greater than flow given on sheet 'Q-Peak'
Inlet A-3 (5 FT TYPE R) - Copy.xlsm, Q-Allow 9/10/2014, 8:03 AM
Project =
Inlet ID =
Design Information (Input) MINOR MAJOR
Type of Inlet Inlet Type =
Local Depression (additional to continuous gutter depression 'a' from 'Q-Allow') alocal
= 3.00 3.00 inches
Number of Unit Inlets (Grate or Curb Opening) No = 1 1
Water Depth at Flowline (outside of local depression) Ponding Depth = 6.0 8.8 inches
Grate Information MINOR MAJOR
Length of a Unit Grate Lo
(G) = N/A N/A feet
Width of a Unit Grate Wo
= N/A N/A feet
Area Opening Ratio for a Grate (typical values 0.15-0.90) Aratio
= N/A N/A
Clogging Factor for a Single Grate (typical value 0.50 - 0.70) Cf
(G) = N/A N/A
Grate Weir Coefficient (typical value 2.15 - 3.60) Cw
(G) = N/A N/A
Grate Orifice Coefficient (typical value 0.60 - 0.80) Co
(G) = N/A N/A
Curb Opening Information MINOR MAJOR
Length of a Unit Curb Opening Lo
(C) = 5.00 5.00 feet
Height of Vertical Curb Opening in Inches Hvert
= 6.00 6.00 inches
Height of Curb Orifice Throat in Inches Hthroat
= 6.00 6.00 inches
Angle of Throat (see USDCM Figure ST-5) Theta = 63.40 63.40 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 2.3-3.6) Cw
(C) = 3.60 3.60
Curb Opening Orifice Coefficient (typical value 0.60 - 0.70) Co
(C) = 0.67 0.67
MINOR MAJOR
Total Inlet Interception Capacity (assumes clogged condition) Q
a = 5.4 10.4 cfs
Inlet Capacity IS GOOD for Minor and Major Storms (>Q PEAK) Q
PEAK REQUIRED = 0.5 1.2 cfs
INLET IN A SUMP OR SAG LOCATION
Harvest Park - Ziegler Mixed Use
A3
CDOT Type R Curb Opening
H-Vert
H-Curb
W
Lo (C)
Lo (G)
Wo
WP
Inlet A-3 (5 FT TYPE R) - Copy.xlsm, Inlet In Sump 9/10/2014, 8:03 AM
D
APPENDIX D
WATER QUALITY POND SIZING
Lot 2, Harvest Park / Ziegler Mixed Use
Proposed WQ Pond - Stage/Storage
LOCATION: Water Quality Pond
PROJECT NO: 1154-095-00
COMPUTATIONS BY: SMB
DATE: 9/9/2014
V = 1/3 d ( A + B + sqrt(A*B))
where V = volume between contours, ft3
d = depth between contours, ft
A = surface area of contour
WATER QUALITY REQD: 0.09 (Ac-Ft)
DETENTION REGD: 0.0 (Ac-Ft)
TOTAL REQD: 0.09 (Ac-Ft)
Surface Incremental Total
Stage Area Storage Storage
(Elev) (Ft^2) (Ac-ft) (Ac-ft)
2.5 0
3.0 235 0.00 0.00
4.0 1250 0.02 0.02
5.0 2440 0.04 0.06
WQ WSEL- 5.6 3515 0.04 0.10
6.0 4232 0.04 0.13
SPILL- 6.3 4783 0.03 0.16
TOP OF BERM - 7.0 6435
detention-FINAL.xls
Water Qualtiy Pond
Emergency Overflow Spillway Sizing
LOCATION: Water Quality Pond
PROJECT NO: 1154-095-00
COMPUTATIONS BY: SMB
DATE: 9/9/2014
Equation for flow over a broad crested weir
Q = CLH3/2
where C = weir coefficient = 2.6
H = overflow height
L = length of the weir
The pond has a spill elevation equal to the maximum water surface elevation in the pond
Design spillway with 1.0 ft flow depth, thus H = 0.7 ft
Size the spillway assuming that the pond outlet is completely clogged.
Pond
Q (100) = 22.2 cfs (peak flow into pond)
Spill elev = 4906.30 ft = 100-year WSEL
Min top of berm elev.= 4907.00
Weir length required:
L = 15 ft
Use L = 15 ft
v = 1.82 ft/s
spillway, detention-FINAL.xls
E
APPENDIX E
FLOODPLAIN INFORMATION