HomeMy WebLinkAboutZIEGLER - HARVEST PARK PDP - PDP120033 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORTPRELIMINARY DRAINAGE REPORT
Harvest Park / Ziegler Mixed Use
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
December 5, 2012
Job Number 1054-095-00
ii
December 5, 2012
Mr. Wes Lamarque
City of Fort Collins Stormwater
700 Wood Street
Fort Collins, CO 80522-0580
RE: Preliminary Drainage Report for Harvest Park / Ziegler Mixed Use
Dear Wes,
I am pleased to submit for your review and approval, this Preliminary Drainage Report for the
Harvest Park / Ziegler Mixed Use development. I certify that this report for the drainage design
was prepared in accordance with the criteria in the City of Fort Collins Storm Drainage Manual.
I appreciate your time and consideration in reviewing this submittal. Please call if you have any
questions.
Sincerely, Reviewed By:
Skylar Brower, P.E. Robert Almirall, P.E.
Colorado Professional Colorado Professional
Engineer No. 44248 Engineer No. 33441
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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 ................................................................................................ 3
2.2 Sub-basin Description .................................................................................................... 3
3. DRAINAGE DESIGN CRITERIA ...................................................................................... 2
3.1 Regulations ...................................................................................................................... 2
3.2 Development Criteria Reference and Constraints ...................................................... 2
3.3 Hydrological Criteria ..................................................................................................... 3
3.4 Hydraulic Criteria .......................................................................................................... 3
3.5 Floodplain Regulations Compliance ............................................................................. 3
4. DRAINAGE FACILITY DESIGN ....................................................................................... 4
4.1 General Concept ............................................................................................................. 4
4.2 Specific Flow Routing .................................................................................................... 4
4.3 Drainage Summary ........................................................................................................ 6
5. CONCLUSIONS .................................................................................................................... 6
5.1 Compliance with Standards .......................................................................................... 6
5.2 Drainage Concept ........................................................................................................... 6
6. REFERENCES ...................................................................................................................... 7
APPENDIX
VICINITY MAP AND DRAINAGE PLAN .............................................................................. A
HYDROLOGIC COMPUTATIONS .......................................................................................... B
HYDRAULIC COMPUTATIONS (to be provided with the final report) .............................. C
WATER QUALITY POND SIZING ......................................................................................... D
FLOODPLAIN INFORMATION ............................................................................................... E
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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 4.08 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 preliminary development permit and the north parcel will be developed in the
future. The proposed development consists of approximately 2.42 acres and the future
parcel to the north consists of approximately 1.66 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 has been mapped by the City and there is a 100-yr floodplain associated with the
channel. The channel is not mapped by FEMA. The only improvements that are proposed
in the City Floodplain is the outlet pipe for the proposed water quality pond. This pipe
will discharge near the bottom of the channel. No fill will take place in the floodway.
All excavation associated with the construction of the outlet pipe will be replaced at
existing grade. A floodplain use permit will be required for this work. All work will be
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in compliance with floodplain regulations in Chapter 10 of the City Code.
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.
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 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 two small rain gardens
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
3.3 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.
Water quality volume will be presented in the final drainage report and calculated using
the method recommended in the “Urban Storm Drainage Criteria Manual”. All
calculations will be located in Appendix D.
3.4 Hydraulic Criteria
All hydraulic calculations will be presented in the final drainage report and prepared in
accordance with the City of Fort Collins Drainage Criteria. All calculations will be
included in Appendix C of this report.
Hydraulic calculations will be presented in the final drainage report.
3.5 Floodplain Regulations Compliance
A completed “City of Fort Collins Floodplain Review Checklist for 50% Submittals” has
been included in Appendix E.
All floodway information is in compliance with Chapter 10 of the City of Fort Collins
Municipal Code.
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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.
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 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.
5
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.
Basin 3 includes the south half of the site that will be developed. Proposed
improvements to basin 3 include four buildings, sidewalk, driveways, two rain gardens,
landscape area and the water quality pond. A portion of the runoff from the roofs will be
conveyed to the rain gardens. This runoff will infiltrate through the rain garden media
and then be conveyed via a pipe system to the water quality pond. Portions of the roof
that cannot reach the rain garden will be hard piped directly to the water quality pond.
Runoff from the landscape areas, driveway, and parking lot will be conveyed overland to
the water quality pond. Basin 3 also includes the southern half of the County Fair Lane
roadway improvements. Runoff from the southern 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 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 5 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.
6
This runoff is conveyed to the Harvest Park Pond. This area was accounted for in the
original Harvest Park Drainage Report.
4.3 Drainage Summary
Drainage facilities located outside of the right of way (including the rain gardens, 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 quantity and 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.
7
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 OS-1 2.05 0.50 0.50 0.62 13.9 13.9 12.7 2.0 3.4 9.0
OS-2 OS-2 0.42 0.64 0.64 0.80 7.1 7.1 5.4 0.7 1.2 3.2
1 1 1.09 0.69 0.69 0.87 6.3 6.3 5.0 2.0 3.4 9.4
2 2 0.20 0.81 0.81 1.00 5.0 5.0 5.0 0.5 0.8 2.0
3 3 2.05 0.54 0.54 0.68 6.8 6.8 5.9 2.8 4.9 12.9
4 4 0.68 0.63 0.63 0.79 5.0 5.0 5.0 1.2 2.1 5.3
5 5 0.06 0.79 0.79 0.99 5.0 5.0 5.0 0.1 0.2 0.6
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: 11/29/2012
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 0.42 0.64 55 2.0 4.8 335 1.50 0.016 2.5 2.3 7.1 390 12.2 7.1
1 1.09 0.69 45 2.0 3.9 295 1.00 0.016 2.0 2.4 6.3 340 11.9 6.3
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 2.05 0.54 20 2.0 3.6 345 0.80 0.016 1.8 3.2 6.8 365 12.0 6.8
4 0.68 0.63 16 2.0 2.7 270 2.30 0.016 3.0 1.5 4.2 286 11.6 5.0
5 0.06 0.79 11 2.0 1.5 50 0.50 0.016 1.4 0.6 2.0 61 10.3 5.0
OVERALL SITE 4.08 0.61 240 2.0 10.8 525 0.50 0.013 1.7 5.0 15.8 765 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-PDP.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: 11/29/2012
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 0.42 0.64 0.80 55 2.0 3.1 335 1.50 0.016 2.5 2.3 5.4 390 12.2 5.4
1 1.09 0.69 0.87 45 2.0 2.2 295 1.00 0.016 2.0 2.4 4.7 340 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 2.05 0.54 0.68 20 2.0 2.7 345 0.80 0.016 1.8 3.2 5.9 365 12.0 5.9
4 0.68 0.63 0.79 16 2.0 1.8 270 2.30 0.016 3.0 1.5 3.3 286 11.6 5.0
5 0.06 0.79 0.99 11 2.0 0.5 50 0.50 0.016 1.4 0.6 1.1 61 10.3 5.0
OVERALL SITE 4.08 0.61 0.77 240 2.0 7.4 525 0.50 0.013 1.7 5.0 12.4 765 14.3 12.4
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-PDP.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: 11/29/2012
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 0.42 0.64 7.1 2.52 0.7
1 1.09 0.69 6.3 2.61 2.0
2 0.20 0.81 5.0 2.85 0.5
3 2.05 0.54 6.8 2.56 2.8
4 0.68 0.63 5.0 2.85 1.2
5 0.06 0.79 5.0 2.85 0.1
OVERALL SITE 4.08 0.61 14.3 1.91 4.8
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-PDP.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: 11/29/2012
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 0.42 0.64 7.1 4.31 1.2 1.2
1 1.09 0.69 6.3 4.46 3.4 3.4
2 0.20 0.81 5.0 4.87 0.8 0.8
3 2.05 0.54 6.8 4.38 4.9 4.9
4 0.68 0.63 5.0 4.87 2.1 2.1
5 0.06 0.79 5.0 4.87 0.2 0.2
OVERALL SITE 4.08 0.61 14.3 3.26 8.2 8.2
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-PDP.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: 11/29/2012
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 0.42 0.80 5.4 9.56 3.2 3.2
1 1.09 0.87 5.0 9.95 9.4 9.4
2 0.20 1.00 5.0 9.95 2.0 2.0
3 2.05 0.68 5.9 9.33 12.9 12.9
4 0.68 0.79 5.0 9.95 5.3 5.3
5 0.06 0.99 5.0 9.95 0.6 0.6
OVERALL SITE 4.08 0.77 12.4 7.10 22.2 22.2
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-PDP.xls Q100
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❤ ⑩ ❶ ✐ ❷ ❸ ❹ ❺ ❦ ❻ ❼ ❽ ③ ◗ ❛ t ❯ ❴ ❯ ❬ ❯ t ◗ ❵ ◗ ❬ ❛ ❯ ❵ ❬ ◗ ❚ ❯ ❬ ❭ ✉
✁
✞ ✄ ☛ ☞ ✌ ✍ ✄ ✆ ✔ ✎ ✏ ✄ ✝ ✗ ☛ ✄ ✏ ✕ ✌ ☛ ✑ ✝ ✗ ✞ ✌ ✒ ✓ ✍ ✜ ✌ ✒ ✓ ✓ ✂ ✗ ✓ ✔ ✄ ✄ ☎ ✌ ✕ ✆ ✝ ✝ ✝ ✓ ✓ ✞ ☞ ✕ ✞ ✟ ☞ ✝ ✒ ✠ ✍ ✍ ✡ ☛ ✡ ✌ ✖ ✓ ✓ ✓ ✌ ✔ ✗ ✌ ✔ ✝ ✌ ✓ ✓ ✘ ☞ ✕ ✙ ☞ ✝ ✌ ✍ ✖ ☛ ☞ ☛ ✝ ✚ ✍
✄ ✆ ✛ ✖ ☞ ✖
✢ ✰ ✳ ✻ ✽ ✣ ✯ ✤ ✦ ✤ ✤ ✫ ✩ ✴ ✥ ✬ ✱ ✱ ✥ ✵ ✼ ✥ ✥ ✣ ✩ ✤ ✦ ✦ ✶ ✥ ✶ ✲ ✧ ✣ ✣ ✥ ★ ✩ ✤ ✪ ✫ ✬ ✭ ✮ ✯ ✣ ✦ ✧ ✷ ✷ ✷ ✸ ✸ ✸ ✹ ✹ ✺ ✺ ✺
✾ ✾ ✮ ❄ ✳ ✶ ✩ ✯ ✥ ✱ ✩ ❃ ✼ ✯ ✥ ✣ ❀ ✤ ✿ ✬ ❅ ✦ ✩ ✼ ✦ ❆ ✭ ✶ ✧ ✥ ❇ ✥ ✢ ❁ ❆ ✩ ✳ ✬ ✣ ✯ ❁ ✦ ✴ ❀ ❈ ✵ ✢ ❇ ✩ ✯ ✶ ✣ ✫ ✶ ✲ ✷ ✷ ✷ ✷ ✸ ✸ ✸ ✸ ✹ ✁ ❂ ✁ ✺ ✺
✢ ✮ ❄ ✳ ✢ ✣ ✶ ✣ ✩ ✱ ✥ ✩ ✥ ❃ ✥ ✥ ✣ ✥ ✤ ✴ ✴ ✬ ❅ ✩ ✦ ❆ ✭ ❉ ❉ ✧ ❇ ✥ ❈ ❈ ❊ ❇ ❇ ❆ ✥ ✩ ✣ ✯ ✱ ❀ ❈ ❇ ✢ ✯ ✫ ✶ ✲ ✷ ✷ ✷ ✷ ✸ ✸ ✸ ✸ ❋ ❆ ❆ ❆ ✺ ✺
● ❙ ❚ ❯ ❍ ✳ ✬ ✰ ✼ ✭ ✔ ✥ ✶ ✫ ✤ ✩ ✱ ❃ ✩ ✌ ✦ ✥ ✫ ✦ ✘ ✬ ✬ ■ ✫ ✿ ✩ ❏ ✙ ❁ ✫ ✭ ❑ ✼ ✌ ✤ ✥ ▲ ✩ ✩ ✖ ▼ ✣ ✫ ◆ ☞ ✦ ✫ ✬ ☛ ❖ ✯ ❱ ✝ ✩ ✬ ❲ ✭ P ✞ ✦ ❳ ✥ ◗ ❲ ✸ ❘ ✒ ✩ ✦ ✍ ✫ ❱ ✦ ❭ ✦ ✬ ✌ ✫ ❲ ✬ ✩ ✓ ❳ ✦ ✦
✓ ❲ ❁ ❱ ✩ ✔ ❁ ✩ ✼ ✦ ✤ ✥ ✵ ✌ ✥ ✫ ❁ ✬ ✝ ✧ ✿ ✼ ✸ ✓ ✤ ✣ ✩ ✓ ✥ ✯ ☞ ✦ ✕ ❨ ✥ ✤ ☞ ❱ ✦ ✥ ✝ ✥ ✩ ✍ ✩ ✬ ❁ ☛ ✣ ✼ ✶ ✩ ❀ ✯ ✦ ❩ ✼ ✿ ✯ ✯ ✴ ❩ ✶ ✯ ✶ ✯ ✦ ✴ ✫ ❃ ✯ ✣ ✥ ✦ ✦ ✥ ✲ ✤ ❁ ❱ ✬ ✯ ✯ ✿ ✿ ✶ ✿ ✩ ✬ ✼ ❁
✯ ✥ ✣ ✿ ✵ ✿ ✩ ✫ ✼ ✣ ✫ ✵ ✥ ✩ ✬ ✦ ✣ ❩ ❩ ❱ ❱ ✶ ✦ ✣ ✣ ✫ ✴ ❲ ✶ ✥ ✥ ✦ ✼ ❱ ✩ ✤ ✶ ✼ ✿ ✩ ❱ ✼ ✶ ✩ ✥ ✣ ✦ ✥ ✯ ❁ ✤ ✿ ❬ ✯ ✯ ✤ ✬ ✩ ✫ ✬ ✬ ✭ ❀
❪ ✵ ✥ ✼ ✯ ❩ ✴ ✯ ✦ ✫ ✣ ✥ ✤ ❱ ✬ ✯ ✿ ✿ ✼ ✯ ✥ ✿ ✿ ✫ ✼ ✫ ✥ ✬ ✣ ✫ ✦ ✯ ❲ ✣ ✩ ✫ ✬ ✥ ❁ ❱ ✦ ✫ ✬ ✭ ✣ ✵ ✥ ✿ ✯ ✶ ✶ ✯ ❃ ✫ ✬ ✭ ✿ ✯ ✤ ❩ ❱ ✶ ✩ ✲
❵ ❴ ( ❫ )
❜ ❜ ❛ ❵ ❛ ❵
= = ❝ ❞ ● ✾ ❡ ❳ ❂ ❍
❢ ✵ ✥ ✤ ✥ ✲ ✳ ✬ ✻ ✳ ✻ ❤ ❤ ❦ ❣ ❣ ❣ ❣ ❣ ❥ ✻ ❪ ✾ ✳ ❱ ✯ ✯ ❱ ✤ ❩ ❩ ✣ ✥ ✬ ✩ ✩ ❲ ✯ ✴ ✶ ✥ ✿ ✯ ✯ ✳ ✿ ✤ ✿ ✦ ✤ ✻ ✫ ✯ ✢ ✥ ✣ ✿ ✥ ✯ ✩ ❱ ✥ ❁ ✤ ✾ ✯ ✿ ✿ ✫ ✿ ✱ ✿ ✩ ❱ ✫ ✿ ✼ ✥ ✬ ✼ ✥ ✥ ✤ ✫ ✯ ✤ ✥ ✥ ❃ ✿ ❃
✬ ✿ ✬ ✵ ✣ ✫ ✣ ✻ ✣ ✫ ✿ ✵ ✦ ✼ ✯ ✯ ❱ ✵ ✾ ✥ ✤ ✤ ✿ ✿ ✻ ✢ ❱ ✿ ✩ ✫ ✴ ✬ ✼ ✼ ✫ ✥ ✯ ✥ ✦ ✫ ✼ ✥ ✿ ✦ ✩ ✿ ✫ ✬ ✿ ✣ ✴ ✣ ✻ ✯ ✫ ✴ ✼ ✯ ❲ ✶ ✳ ✫ ✥ ✥ ✼ ✿ ✤ ✩ ✿ ✼ ✥ ❲ ✫ ✯ ✩ ✼ ✶ ✬ ✫ ✥ ● ✥ ✦ ✧ ✳ ✬ ✫ ✩ ❁ ✣ ❤
✼ ❍ ✥ ✯ ✤ ✤ ✥ ✿ ✥ ✦ ❁ ✻ ✯ ❤ ✧ ✤ ✩ ✿ ✼ ✥ ✤ ✥ ✥ ✣ ✦ ✐ ✯ ✤ ✿ ✥ ✥ ✣ ✐
● ✺ ❍ ✳ ✬ ✥ ❃ ■ ❏ ❑ ▲ ▼ ◆ ❖ P ◗ ❧ ♠ ✫ ✦ ✩ ❁ ❁ ✥ ❁ ✧ ✣ ✯ ✤ ✥ ✩ ❁ ✩ ✦ ✿ ✯ ✶ ✶ ✯ ❃ ✦ ✲
10
15
20
25
100-yr Storm Hydrograph
100-yr Storm Hydrograph
0
5
10
0 20 40 60 80 100 120
Summary of Unit Hydrograph Parameters Used By Program and Calculated Results (Version 1.3.3)
Catchment Name/ID User Comment for Catchment Ct Cp
W50
(min.)
W50
Before
Peak
W75
(min.)
W75
Before
Peak
Time to
Peak
(min.) Peak (cfs)
Volume
(c.f)
Excess
(inches)
Excess
(c.f.)
Time to
Peak
(min.)
Peak Flow
(cfs)
Overall Site 0.273 0.295 15.5 5.02 8.1 3.55 8.4 12 14,868 3.35 49,769 35.0 20
Unit Hydrograph Parameters and Results Excess Precip. Storm Hydrograph
Total
Volume
(c.f.)
49,681
torm Hydrograph
Summary of CUHP Input Parameters (Version 1.3.3)
Catchment Name/ID Raingage Name/ID
Area
(sq.mi.)
Dist. to
Centroid
(miles)
Length
(miles)
Slope
(ft./ft.)
Percent
Imperv.
Pervious
(inches)
Imperv.
(inches)
Initial Rate
(in./hr.)
Final Rate
(in.hr.)
Decay
Coeff.
(1/sec.) DCIA Level
Dir. Con'ct
Imperv.
Fraction
Receiv.
Perv.
Fraction
Percent Eff.
Imperv.
Overall Site COFC 100-YR 0.006 0.073 0.145 0.008 53.0 0.35 0.10 3.00 0.50 0.0018 1.00 0.64 0.39 50.82
Depression Storage Horton's Infiltration Parameters DCIA Level and Fractions
C
APPENDIX C
HYDRAULIC CALCULATIONS
(To be provided with the Final Report)
D
APPENDIX D
WATER QUALITY POND SIZING
Harvest Park / Ziegler Mixed Use
Proposed Detention Pond - Stage/Storage
LOCATION: Water Quality Pond
PROJECT NO: 1154-095-00
COMPUTATIONS BY: SMB
DATE: 12/4/2012
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: 0.00 (Ac-Ft)
TOTAL REQD: 0.09 (Ac-Ft)
Surface Incremental Detention Total
Stage Area Storage Storage Storage
(Elev) (Ft^2) (Ac-ft) (Ac-ft) (Ac-ft)
3.4 0
4.0 408 0.00 0.00 0.00
5.0 2077 0.03 0.00 0.03
WQ WSEL- 5.8 4087 0.08 0.00 0.08
6.0 4496 0.02 0.02 0.10
TOP OF BERM - 7.0
Note: The remaining 0.01 ac-ft of required water quality capture volume will be handled with
the use a two rain gardens that treat approximately 0.007 ac-ft each.
detention-PDP.xls
Sheet 1 of 3
Designer:
Company:
Date:
Project:
Location:
1. Basin Storage Volume
Ia
= 53.00 %
A) Tributary Area's Imperviousness Ratio (i = Ia
/ 100 ) i = 0.53
B) Contributing Watershed Area (Area) Area = 4.080 acres
C) Water Quality Capture Volume (WQCV) WQCV = 0.21 watershed inches
(WQCV =1.0 * (0.91 * I
3
- 1.19 * I
2
+ 0.78 * I))
D) Design Volume: Vol = (WQCV / 12) * Area * 1.2 Vol = 0.0876 acre-feet
2. Outlet Works
A) Outlet Type (Check One) X Orifice Plate
Perforated Riser Pipe
Other:
B) Depth at Outlet Above Lowest Perforation (H) H = 2.00 feet
C) Recommended Maximum Outlet Area per Row, (Ao
) Ao
= 0.2 square inches
D) Perforation Dimensions:
i) Circular Perforation Diameter or D = 0.375 inches
ii) Width of 2" High Rectangular Perforations W = inches
E) Number of Columns (nc, See Table 6a-1 For Maximum) nc = 1 number
F) Actual Design Outlet Area per Row (Ao
) Ao
= 0.1 square inches
G) Number of Rows (nr) nr = 6 number
H) Total Outlet Area (Aot
) Aot
= 0.7 square inches
3. Trash Rack
A) Needed Open Area: At
= 0.5 * (Figure 7 Value) * Aot
At
= 24 square inches
B) Type of Outlet Opening (Check One) X < 2" Diameter Round
2" High Rectangular
Other:
C) For 2", or Smaller, Round Opening (Ref.: Figure 6a):
i) Width of Trash Rack and Concrete Opening (Wconc
)
from Table 6a-1 Wconc
= 3 inches
ii) Height of Trash Rack Screen (HTR
) HTR
= 54 inches
Design Procedure Form: Extended Detention Basin (EDB) - Sedimentation Facility
Interwest Consulting Group
Ziegler Mized Use - PDP
December 4, 2012
smb
UD-BMP_v2.06.xls, EDB 12/4/2012, 8:08 AM
Sheet 2 of 3
Designer:
Company:
Date:
Project:
Location:
iii) Type of Screen (Based on Depth H), Describe if "Other" S.S. #93 VEE Wire (US Filter)
Other:
iv) Screen Opening Slot Dimension, Describe if "Other" 0.139" (US Filter)
Other:
v) Spacing of Support Rod (O.C.) inches
Type and Size of Support Rod (Ref.: Table 6a-2)
vi) Type and Size of Holding Frame (Ref.: Table 6a-2)
D) For 2" High Rectangular Opening (Refer to Figure 6b):
I) Width of Rectangular Opening (W) W = inches
ii) Width of Perforated Plate Opening (Wconc
= W + 12") Wconc
= inches
iii) Width of Trashrack Opening (Wopening
) from Table 6b-1 Wopening
= inches
iv) Height of Trash Rack Screen (HTR
) HTR
= inches
v) Type of Screen (based on depth H) (Describe if "Other") Klemp
TM
KPP Series Aluminum
Other:
vi) Cross-bar Spacing (Based on Table 6b-1, Klemp
TM
KPP inches
Grating). Describe if "Other" Other:
vii) Minimum Bearing Bar Size (Klemp
TM
Series, Table 6b-2)
(Based on depth of WQCV surcharge)
4. Detention Basin length to width ratio (L/W)
5 Pre-sedimentation Forebay Basin - Enter design values
A) Volume (3% to 5% of Design Volume from 1D) acre-feet
(3% - 5% of Design Volume (0.0026 - 0.0044 acre-feet.)
B) Surface Area acres
C) Connector Pipe Diameter inches
(Size to drain this volume in 5-minutes under inlet control)
D) Paved/Hard Bottom and Sides yes/no
smb
Interwest Consulting Group
Design Procedure Form: Extended Detention Basin (EDB) - Sedimentation Facility
December 4, 2012
Ziegler Mized Use - PDP
UD-BMP_v2.06.xls, EDB 12/4/2012, 8:08 AM
Sheet 3 of 3
Designer:
Company:
Date:
Project:
Location:
6. Two-Stage Design - See Figure EDB-1
A) Top Stage (Depth DWQ
= 2' Minimum) DWQ
= feet
Top Stage Storage: no less than 99.5% of Design Volume (0.0872 acre-feet.) Storage= acre-feet
B) Bottom Stage Depth (DBS
= 0.33' Minimum Below Trickle Channel Invert) DBS
= feet
Bottom Stage Storage: no less than 0.5% of Design Volume (0.0004 acre-feet.) Storage= acre-feet
Storage = A * Depth Above WS To Bottom Of Top Stage Surf. Area= acres
C) Micro Pool (Minimum Depth = the Larger of Depth= feet
0.50 * Top Stage Depth or 2.5 Feet)
D) Total Volume: Voltot
= Storage from 5A + 6A + 6B Voltot
= acre-feet
(Must be > Design Volume in 1D, or 0.0876 acre-feet.)
7. Basin Side Slopes (Z, horizontal distance per unit vertical) Z = (horizontal/vertical)
Minimum Z = 4, Flatter Preferred
8. Dam Embankment Side Slopes (Z, horizontal distance) Z = (horizontal/vertical)
per unit vertical) Minimum Z = 3, Flatter Preferred
9. Vegetation (Check the method or describe "Other") Native Grass
Irrigated Turf Grass
Other:
Notes:
smb
Interwest Consulting Group
December 4, 2012
Design Procedure Form: Extended Detention Basin (EDB) - Sedimentation Facility
Ziegler Mized Use - PDP
UD-BMP_v2.06.xls, EDB 12/4/2012, 8:08 AM
Sheet 1 of 2
Designer:
Company:
Date:
Project:
Location:
1. Basin Storage Volume
A) Effective Imperviousness of Tributary Area, Ia Ia = 100.0 %
(100% if all paved and roofed areas upstream of rain garden)
B) Tributary Area's Imperviousness Ratio (i = Ia/100) i = 1.000
C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.40 watershed inches
(WQCV= 0.8 * (0.91* i3 - 1.19 * i2 + 0.78 * i)
D) Contributing Watershed Area (including rain garden area) Area = 9,755 sq ft
E) Water Quality Capture Volume (WQCV) Design Volume VWQCV = 325 cu ft
Vol = (WQCV / 12) * Area
F) For Watersheds Outside of the Denver Region, Depth of d6 = in
Average Runoff Producing Storm
G) For Watersheds Outside of the Denver Region, VWQCV OTHER = cu ft
Water Quality Capture Volume (WQCV) Design Volume
H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER = cu ft
(Only if a different WQCV Design Volume is desired)
2. Basin Geometry
A) WQCV Depth (12-inch maximum) DWQCV = 8 in
B) Rain Garden Side Slopes (Z = 4 min., horiz. dist per unit vertical) Z = 4.00 ft / ft
(Use "0" if rain garden has vertical walls)
C) Mimimum Flat Surface Area AMin = 217 sq ft
D) Actual Flat Surface Area AActual = 747 sq ft
E) Area at Design Depth (Top Surface Area) ATop = 1029 sq ft
F) Rain Garden Total Volume VT= 592 cu ft
(VT= ((ATop + AActual) / 2) * Depth)
3. Growing Media
4. Underdrain System
A) Are underdrains provided?
B) Underdrain system orifice diameter for 12 hour drain time
i) Distance From Lowest Elevation of the Storage y = 30.0 ft
Volume to the Center of the Orifice
ii) Volume to Drain in 12 Hours Vol12 = 325 cu ft
iii) Orifice Diameter, 3/8" Minimum DO = 0.24 in MINIMUM DIAMETER = 3/8"
Design Procedure Form: Rain Garden (RG)
sb
Interwest Consulting Group
December 4, 2012
Ziegler Mixed Use
Choose One
Choose One
18" Rain Garden Growing Media
Other (Explain):
YES
NO
UD-BMP_v3_01 Rain Garden.xls, RG 12/4/2012, 8:07 AM
Sheet 2 of 2
Designer:
Company:
Date:
Project:
Location:
5. Impermeable Geomembrane Liner and Geotextile Separator Fabric
A) Is an impermeable liner provided due to proximity
of structures or groundwater contamination?
6. Inlet / Outlet Control
A) Inlet Control
7. Vegetation
8. Irrigation
A) Will the rain garden be irrigated?
Notes:
Design Procedure Form: Rain Garden (RG)
sb
Interwest Consulting Group
December 4, 2012
Ziegler Mixed Use
Choose One
Choose One
Choose One
Sheet Flow- No Energy Dissipation Required
Concentrated Flow- Energy Dissipation Provided
Plantings
Seed (Plan for frequent weed control)
Sand Grown or Other High Infiltration Sod
Choose One
YES
NO
YES
NO
UD-BMP_v3_01 Rain Garden.xls, RG 12/4/2012, 8:07 AM
E
APPENDIX F
FLOODPLAIN INFORMATION