HomeMy WebLinkAboutTHE LEARNING EXPERIENCE @ MIRAMONT OFFICE PARK - PDP - PDP130023 - REPORTS - DRAINAGE REPORTFinal Drainage Report
The Learning Experience
at Miramont Office Park
Prepared for:
Adam Rubenstein
Rubenstein Real Estate Company
C/O The Legend Retail Group
5150 E. Yale Circle, Suite 400
Denver, CO 80222
720-529-2881
arubenstein@legendretailgroup.com
Prepared by:
Contact: Mark Cevaal, PE
mcevaal@redland.com
October 4, 2013
Project No. 12026
Final Drainage Report for The Learning Experience at Miramont Office Park
2
ENGINEER CERTIFICATION OF DRAINAGE REPORT
“I hereby certify that this report (plan) for the drainage design of The Learning
Experience at Miramont Office Park was prepared by me or under my direct supervision
in accordance with the provisions of The Fort Collins Amendments to the Urban
Drainage and Flood Control District Criteria Manual for the owners thereof.”
_______________________________ _____________________________
Mark D. Cevaal, P.E. Date
Licensed Professional Engineer
State of Colorado No. 33123
Final Drainage Report for The Learning Experience at Miramont Office Park
3
Table of Contents
General Location and Description ............................................................................. 4
Project Introduction ............................................................................................. 4
Project Location .................................................................................................. 4
Site Description ................................................................................................... 4
Floodplain Submittal Requirements .................................................................... 5
Drainage Basin and Sub-Basins ............................................................................... 5
Major Basin ......................................................................................................... 5
Sub Basin Descriptions ....................................................................................... 5
Drainage Design Criteria ........................................................................................... 8
Regulations ......................................................................................................... 8
Directly Connected Impervious Area (DCIA) ....................................................... 8
Development Reference Criteria ......................................................................... 8
Hydrologic and Hydraulic Criteria ........................................................................ 8
Floodplain Regulations Compliance .................................................................... 9
Drainage Facility Design ........................................................................................... 9
General Concept ................................................................................................. 9
Specific Details ................................................................................................. 10
Conclusion .............................................................................................................. 11
Compliance with Standards .............................................................................. 11
Drainage Concept ............................................................................................. 11
References ............................................................................................................. 12
Appendix A - Vicinity Map and Soils Map
Appendix B - Hydrologic Drainage Calculations
Appendix C - Hydraulic Drainage Calculations
Appendix D - Reference Documents and Excerpts
Appendix E - Proposed Drainage Plan
Final Drainage Report for The Learning Experience at Miramont Office Park
4
General Location and Description
Project Introduction
This PDP Drainage report for Lot 3 of the Miramont Office Park (the Site) covers the
development of one 10,000 square foot building with parking and utility infrastructure.
The proposed development will modify an existing detention pond to accommodate the
new development and provide water quality.
The site will be developed into a single story 10,000 square foot daycare building which
will utilize an existing parking lot. Improvements include dry and wet utilities, curb and
gutter modifications and the building. The building will be utilized as an early childhood
development center with a playground.
Project Location
The project is located in the northeast quarter of Section 1, Township 6 North, Range 69
West of the 6
th
Principal Meridian in the City of Fort Collins, Larimer County, State of
Colorado. See the Vicinity Map in Appendix A.
More specifically it is located within the Miramont Office Park at the northwest corner of
Boardwalk Drive and Oakridge Drive. The Site is bounded by existing office buildings to
the north, Front Range Baptist Church to the west, Miramont Self-Storage to the south
and Boardwalk Drive to the east. There are no major drainage ways or facilities on site.
An existing detention pond for the Miramont Office Park is located on Lot 3 and will be
modified with this development.
Site Description
Lot 3 of the Miramont Office Park is 1.614 acres. Currently the west half of the lot is
developed as a parking lot with an access drive along the southern boundary. The east
half has been overlot graded for a commercial building pad. An existing detention pond
is located south of the pad site and serves the entire Miramont Office Park.
The undeveloped portions of Lot 3 are covered in native weeds and grasses. The site
has relatively mild grades (<2%) and no major drainage ways cross the site. The soils
on site are Nunn Clay Loam which is Type C according the NRCS Soil Survey. Type C
soils have slow infiltration rates when wet and have a slow rate of water transmission.
The proposed site will be developed into a single story early childhood development
center.
Final Drainage Report for The Learning Experience at Miramont Office Park
5
Floodplain Submittal Requirements
The proposed Site is not located within the 100 year floodplain.
Drainage Basin and Sub-Basins
Major Basin
The project site is located within the City of Fort Collins McClellands Basin. No major
drainage ways exist on site.
According to the Final Drainage and Erosion Control Study of Miramont Office Park
dated December 1997 the site is within Basin 202 of the McClelland’s Basin Regional
SWMModel. This basin includes the Miramont Office Park, Miramont Self Storage PUD,
Front Range Baptist Church and Bank One at Harmony Market. Each of the four sites
within this basin will need to provide on-site detention.
Currently and in accordance with the Final Drainage and Erosion Control Study of
Miramont Office Park on-site detention is provided at the southeast corner of the site.
The site receives off-site flows from the church to the west. A swale along this property
line collects these flows and directs them to the southeast access drive of the Office
Park where they are released to Boardwalk Drive.
Sub Basin Descriptions
The overall drainage patterns, discharges and basin boundaries have not been modified
from the Final Drainage and Erosion Control Study of Miramont Office Park. However,
in order to accurately size the pond and associated structures the entire area tributary to
the pond had to be analyzed. This analysis results in 10 basins: 7 tributary to the pond
and 3 that direct flows off-site.
Basin A1
Design
Point
Area
(AC) C2 C5 C100 I%
Q
(2 year)
Q
(100 Year)
A1 2.26 0.64 0.67 0.81 73.2% 2.82 12.50
Basin A1 is the northern portion of the Office Park and is comprised mainly of the
developed Lots 1 and 2. This basin is fully developed and contains 4 existing
commercial buildings and associated parking. Runoff sheet flows to curb and gutter
where it is directed south to design point A1. Currently, a 6’ curb cut directs these flows
to the pond. This curb cut will be removed and replaced with a 15’ Type R Inlet. This
inlet will direct the flows via a storm sewer to the modified detention and water quality
pond.
Final Drainage Report for The Learning Experience at Miramont Office Park
6
Basin A2
Design
Point
Area
(AC) C2 C5 C100 I%
Q (2
year)
Q (100
Year)
A2 0.65 0.74 0.77 0.87 83.9 1.23 5.05
Basin A2 is the portion of the Lot 3 located west of the proposed building. This basin is
fully developed and is comprised entirely of existing parking lot and landscaping. Runoff
from this basin will sheet flow to the curb and gutter adjacent to the building. Currently,
a two 2-foot wide curb cuts direct these flows to the pond at design point A2. These
curb cuts will be removed and replaced with a 10’ Type R Inlet. This inlet will direct the
flows via a storm sewer to the modified detention and water quality pond
Basin A3
Design
Point
Area
(AC) C2 C5 C100 I%
Q (2
year)
Q (100
Year)
A3 0.21 0.07 0.18 0.52 4.2 0.04 1.07
Basin A3 is the modified detention and water quality pond. This basin will remain
landscaped. Runoff from this basin will sheet flow directly to the pond.
Basin A4
Design
Point
Area
(AC) C2 C5 C100 I%
Q (2
year)
Q (100
Year)
A4 0.13 0.11 0.21 0.54 9.7 0.04 0.59
Basin A4 is the playground located east of the proposed building. This basin will contain
playground equipment and mulch for the childhood development center. Runoff from
this basin will be captured in an underdrain along the eastern edge of the playground.
This underdrain will divert the flows to the proposed storm sewer system at design point
A4 where they will outfall into the modified detention and water quality pond.
Basin A5
Design
Point
Area
(AC) C2 C5 C100 I%
Q (2
year)
Q (100
Year)
A5 0.11 0.73 0.75 0.83 90 0.22 0.86
Basin A5 is the west half of the proposed building’s roof. Roof drains will collect flows
from the roof and outfall the flow via storm sewer directly into the modified detention and
water quality pond.
Final Drainage Report for The Learning Experience at Miramont Office Park
7
Basin A6
Design
Point
Area
(AC) C2 C5 C100 I%
Q (2
year)
Q (100
Year)
A6 0.11 0.73 0.75 0.83 90 0.22 0.86
Basin A6 is the east half of the proposed building’s roof. Roof drains will collect flows
from the roof and outfall the flow via storm sewer directly into the modified detention and
water quality pond.
Basin A7
Design
Point
Area
(AC) C2 C5 C100 I%
Q (2
year)
Q (100
Year)
A7 0.18 0.46 0.51 0.70 54.1 0.19 1.04
Basin A7 is the west half of the roofs of the two existing commercial buildings on Lot 2.
Flows from this basin are directed to swale along the western property line that outfalls
into a 2’ curb cut at the northwest corner of Basin A2. This is an existing condition that is
not changed by the proposed development. This runoff will sheet flow across Basin A2
and enter the new 10’ Type R inlet at design point A2.
Basin B1
Design
Point
Area
(AC) C2 C5 C100 I%
Q (2
year)
Q (100
Year)
B1 0.38 0.65 0.69 0.83 72.6 0.69 3.05
Basin B1 is the existing access drive along the southern property line of the Miramont
Office Park. This access drive sheet flows undetained in Boardwalk Drive. This
condition is unchanged from its description in the Final Drainage and Erosion Control
Study of Miramont Office Park. Runoff from Front Range Baptist Church discharge into
a swale that outfalls into the access drive as is discussed in the previous report as well.
Basin B2
Design
Point
Area
(AC) C2 C5 C100 I%
Q (2
year)
Q (100
Year)
B2 0.76 0.64 0.68 0.82 72.5 1.06 4.71
Basin B2 is the west half of Boardwalk Drive and its adjacent right of way. A small
portion of the on-site areas will sheet flow directly towards the right of way and be
Final Drainage Report for The Learning Experience at Miramont Office Park
8
captured by the curb and gutter along Boardwalk Drive. These flows will be directed to
the south.
Basin B3
Design
Point
Area
(AC) C2 C5 C100 I%
Q (2
year)
Q (100
Year)
B3 0.06 0.57 0.62 0.79 62.2 0.09 0.42
Basin B2 is the south half of the shared access drive with Bank One. This basin will
sheet flow undetained to the east and discharge into Boardwalk Drive and is unchanged
by the proposed development.
Drainage Design Criteria
Regulations
This report is in compliance with the City of Fort Collins Amendments to the Urban
Drainage and Flood Control District Criteria Manual.
Directly Connected Impervious Area (DCIA)
Since the majority of the site is currently developed as a parking lot; therefore,
incorporating directly connected impervious area and LID techniques is not required.
The existing detention pond is being modified with the new development to remove the
existing concrete low flow channel and replacing it with a grass swale to allow for some
infiltration and sediment removal. The addition of the water quality control volume to the
pond will also allow time for sediment and impurities to settle out of the runoff.
Development Reference Criteria
As previously mentioned, the Final Drainage and Erosion Control Study of Miramont
Office Park dated December 1997 analyzes the drainage patterns for the site. The
overall drainage plan and off-site conditions discussed in this report are still valid and
are not changed by the proposed development.
Hydrologic and Hydraulic Criteria
Hydrologic and hydraulic analysis has been completed to meet the standards of the City
of Fort Collins Amendments to the Urban Drainage and Flood Control District Criteria
Manual as well as the Urban Drainage Flood Control District (UDFCD) Manual.
The Rational Method was used to calculate the flows for each basin. Each basin was
analyzed for different land uses and a composite coefficient and imperviousness was
Final Drainage Report for The Learning Experience at Miramont Office Park
9
calculated. 2 year run-off coeffecients were taken from Table RO-11 of the Fort Collins
Criteria Manual and the frequency factors in Table RO-12 were applied to generate the
5, 10 and 100-year factors.
Rainfall intensities for the one-hour storm are listed on Table RA-8 City of Fort Collins.
These tables have been included in the appendix for reference.
Design storm return periods are 2-year for the minor event and 100-year for the major
event. The pond has been sized to detain the 10-year and 100-year storm events.
The detention pond and its outfall structure were designed using UD_Detentionv2.32
from Urban Drainage and Flood Control District (UDFCD). The FAA Method was used
to size the pond with a 10-year discharge of 0.2 cfs/acre and a 100-year discharge of
0.50 cfs/acre. These release rates were provided by the City of Fort Collins during their
Conceptual Project Review.
The storm sewer system for the Site is designed to convey the major event, while
keeping the hydraulic and energy grade lines below finished grade. Emergency
overflow routes have been designed to convey flows to the adjacent streets in the event
an inlet becomes obstructed. All of the inlets on site were sized using UD_Inlet v3.12
from UDFCD to handle the 100-year flow without overtopping the adjacent curb and
gutter.
Floodplain Regulations Compliance
No floodplains existing within the proposed study area.
Drainage Facility Design
General Concept
Stormwater in the office park will sheet flow southeast and be directed by curb and
gutter to proposed inlets. These inlets will direct flows via storm sewer to the proposed
pond. Discharge from the pond will be regulated through a two stage outlet structure
that will outfall across the Miramont Self Storage Lot 2 to the south into a concrete
drainage pan. This pan will direct the flows to Boardwalk Drive’s curb & gutter.
All areas tributary to the existing pond will be discharged into the revised pond. The
revised pond has been sized to provide 10-year and 100-year detention plus water
quality.
Final Drainage Report for The Learning Experience at Miramont Office Park
10
Specific Details
The required storage for the detention and water quality pond has been calculated using
the FAA method. In its existing condition, the pond has a 2 year release rate of 0.09 cfs
and 100 year release rate of 1.80 cfs. These flows were reduced to help compensate for
the undetained flows from Boardwalk Drive and the Front Range Baptist Church per the
Final Drainage and Erosion Control Study of Miramont Office Park. The release rates
for the site as determined by the City of Fort Collins in the conceptual review were set at
0.2 cfs/acre for the 10-year event and 0.50 cfs/acre in the 100-year event. This results
in a 10-year release rate of 0.73 cfs and a 100-year release of 1.83 cfs. These values
are in line with the previous report and should have no negative impacts on downstream
infrastructure
The following table provides specific details about the detention and water quality pond.
DETENTION/WATER QUALITY POND
WQCV REQUIRED = 0.098 AC-FT
WQCV PROVIDED 0.149 AC-FT
10-YR VOLUME REQUIRED 0.33 AC-FT +WQCV=0.428 AC-FT
10-YR VOLUME RPROVIDED 0.435 AC-FT
100-YR VOLUME REQUIRED 0.621 AC-FT +WQCV=0.719 AC-FT
100-YR VOLUME PROVIDED 0.750 AC-FT
WQCV WATER SURFACE ELEVATION 4999.00
10-YR WATER SURFACE ELEVATION 5000.90
100-YR WATER SURFACE ELEVATION 5002.59
OVERFLOW WEIR WATER SURFACE ELEV. 5002.59
10-YR ALLOWABLE RELEASE RATE - BASIN A 0.2 CFS\AC = 0.73 CFS
100-YR ALLOWABLE RELEASE RATE - BASIN A 0.5 CFS\AC = 1.83 CFS
The proposed pond will have a two stage outlet structure with a water quality plate. The
water quality plate will consist of one row of five 0.562-inch diameter holes. At the water
quality water surface elevation, a 4.27 inch diameter hole will provide the 10 year
release. This hole has been sized in conjunction with the water quality plate to restrict
the release to 0.73 cfs when the pond is full to the 10-year water surface elevation. The
top of the structure will be a single Type C Inlet located at the 10-year water surface
elevation. This inlet will collect any volume greater than the 10-year. A restrictor plate
has been sized over the structure’s outlet pipe to reduce the flow to 1.83 cfs when the
pond is full to the 100-year water surface elevation. The existing emergency spillway for
the pond will be maintained. This spillway will provide relief for any volume over the
100-year volume in the pond or if the outlet structure becomes plugged. 1’ of freeboard
Final Drainage Report for The Learning Experience at Miramont Office Park
11
is provided above the spillway elevation. The UD_Detention spreadsheet used to size
the pond and its structures can be found in the Appendix.
A 12” RCP outfall pipe will service the outlet structure and convey the restricted flows to
the south. The pipe will cross the access drive and a portion of Lot 2 Miramont Self
Storage. The pipe will daylight into a 1’ wide concrete drainage channel. This channel
will direct the flows east under the existing walk and into the curb & gutter flowline of
Boardwalk Drive. This outfall pipe falls within an existing 15’ drainage and utility
easement. Approval has been received from the owner of Lot 2 of Miramont Self
Storage to complete the drainage improvements on the property, within the existing
easement.
A forebay will be provided for the 24” RCP pipe that outfalls into the pond at design
point A1. This forebay has been sized to accommodate 1% of the WQCV for its tributary
area. It will be 6” deep and discharge through a 4.2-inch wide rectangular weir at a flow
equivalent to 2% of the 100 year discharge. The other pond outfalls do not require
forebays because their tributary areas are too small. A copy of the UD_BMP
spreadsheet for this design can be found in the Appendix. This sheet was only used for
forebay design and the other elements remain blank.
Maintenance access will be achieved via a gravel access drive along the southern end
of the pond. The gravel access drive is graded not to exceed 10% and provides access
from the existing driveway to the bottom of the pond and the outlet structure.
Both the pond and outfall pipe will be located within the drainage easement on Lot 3 of
Miramont Office Park.
Conclusion
Compliance with Standards
The intent of and computations within this report are in compliance with the City of Fort
Collins Amendments to the Urban Drainage and Flood Control District Criteria Manual
as well as the Urban Drainage and Flood Control District Criteria Manual. It follows the
intent of the McClelland Basin Master Drainage Plan and has no impacts on any
existing floodplains.
Drainage Concept
The proposed drainage concepts shown in the report have been design to create no
negative impact on existing development or drainage facilities. The proposed
improvements will contain storm runoff and discharge it safely and slowly during the
design events. The proposed development is in conformance with the McClelland Basin
Master Drainage Plan.
Final Drainage Report for The Learning Experience at Miramont Office Park
12
References
1. City of Fort Collins, City of Fort Collins Amendments to the Urban
Drainage and Flood Control District Criteria Manual, latest online edition.
2. Urban Drainage and Flood Control District, Denver, Colorado, Urban
Storm Drainage Criteria Manual, Volume 1-3, latest online edition.
3. The Sear-Brown Group, Final Drainage and Erosion Control Study
Miramont Office Park, December 1997
Final Drainage Report for The Learning Experience at Miramont Office Park
13
Appendix A - Vicinity Map
Boardwalk Dr
Oakridge Dr
73
36
494340
494340
494370
494370
494400
494400
494430
494430
494460
494460
494490
494490
4485510
4485510
4485540
4485540
4485570
4485570
4485600
4485600
4485630
4485630
4485660
4485660
4485690
4485690
4485720
4485720
0 40 80 160 240
Feet
0 10 20 40 60
Meters
40° 31' 20''
105° 3' 53''
40° 31' 12''
105° 3' 52''
40° 31' 12''
40° 31' 20''
105° 4' 0'' 105° 4' 0''
Map Scale: 1:1,160 if printed on A size (8.5" x 11") sheet.
Hydrologic Soil Group—Larimer County Area, Colorado
(TLE Miramont)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/20/2013
Page 1 of 4
MAP LEGEND MAP INFORMATION
Area of Interest (AOI)
Area of Interest (AOI)
Soils
Soil Map Units
Soil Ratings
A
A/D
B
B/D
C
C/D
D
Not rated or not available
Political Features
Cities
Water Features
Streams and Canals
Transportation
Rails
Interstate Highways
US Routes
Major Roads
Local Roads
Map Scale: 1:1,160 if printed on A size (8.5" × 11") sheet.
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 accurate map
measurements.
Source of Map: Natural Resources Conservation Service
Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov
Coordinate System: UTM Zone 13N NAD83
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 7, May 1, 2009
Date(s) aerial images were photographed: 8/6/2005
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.
Hydrologic Soil Group–Larimer County Area, Colorado
(TLE Miramont)
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/20/2013
Page 2 of 4
Hydrologic Soil Group
Hydrologic Soil Group— Summary by Map Unit — Larimer County Area, Colorado (CO644)
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
36 Fort Collins loam, 3 to 5
percent slopes
B 0.0 0.2%
73 Nunn clay loam, 0 to 1
percent slope
C 4.3 99.8%
Totals for Area of Interest 4.3 100.0%
Description
Hydrologic soil groups are based on estimates of runoff potential. Soils are
assigned to one of four groups according to the rate of water infiltration when the
soils are not protected by vegetation, are thoroughly wet, and receive precipitation
from long-duration storms.
The soils in the United States are assigned to four groups (A, B, C, and D) and
three dual classes (A/D, B/D, and C/D). The groups are defined as follows:
Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly
wet. These consist mainly of deep, well drained to excessively drained sands or
gravelly sands. These soils have a high rate of water transmission.
Group B. Soils having a moderate infiltration rate when thoroughly wet. These
consist chiefly of moderately deep or deep, moderately well drained or well drained
soils that have moderately fine texture to moderately coarse texture. These soils
have a moderate rate of water transmission.
Group C. Soils having a slow infiltration rate when thoroughly wet. These consist
chiefly of soils having a layer that impedes the downward movement of water or
soils of moderately fine texture or fine texture. These soils have a slow rate of water
transmission.
Group D. Soils having a very slow infiltration rate (high runoff potential) when
thoroughly wet. These consist chiefly of clays that have a high shrink-swell
potential, soils that have a high water table, soils that have a claypan or clay layer
at or near the surface, and soils that are shallow over nearly impervious material.
These soils have a very slow rate of water transmission.
If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is
for drained areas and the second is for undrained areas. Only the soils that in their
natural condition are in group D are assigned to dual classes.
Rating Options
Aggregation Method: Dominant Condition
Hydrologic Soil Group–Larimer County Area, Colorado TLE Miramont
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/20/2013
Page 3 of 4
Component Percent Cutoff: None Specified
Tie-break Rule: Higher
Hydrologic Soil Group–Larimer County Area, Colorado TLE Miramont
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
6/20/2013
Page 4 of 4
Final Drainage Report for The Learning Experience at Miramont Office Park
14
Appendix B - Hydrologic Calculations
The Learning Experience at Miramont DATE:
12026
RAO
MC
Paved Landscape Roof Walks
LAND USE: Area Area Area Area
2-YEAR COEFF. 0.89 0.04 0.73 0.73
5-YEAR COEFF. 0.90 0.15 0.75 0.75
10-YEAR COEFF. 0.92 0.25 0.77 0.77
100-YEAR COEFF. 0.96 0.50 0.83 0.83
IMPERVIOUS % 100% 0% 90% 90%
TOTAL
DESIGN DESIGN AREA
BASIN POINT (AC) (AC) (AC) (AC) (AC) Cc(2) Cc(5) Cc(10) Cc(100) Impervious %
A1 A1 0.99 0.53 0.64 0.10 2.26 0.64 0.67 0.71 0.81 73.2%
A2 A2 0.45 0.09 0.05 0.05 0.65 0.74 0.77 0.80 0.87 83.9%
A3 A3 0.20 0.01 0.21 0.07 0.18 0.27 0.52 4.2%
A4 A4 0.12 0.01 0.13 0.11 0.21 0.31 0.54 9.7%
A5 A5 0.11 0.11 0.73 0.75 0.77 0.83 90.0%
A6 A6 0.11 0.11 0.73 0.75 0.77 0.83 90.0%
A7 A7 0.07 0.11 0.18 0.46 0.51 0.56 0.70 54.1%
1.44 1.02 1.01 0.18 3.65 0.60 0.64 0.68 0.79 68.8%
39.5% 27.9% 27.6% 4.9% 100.0%
B1 B1 0.25 0.10 0.03 0.38 0.65 0.69 0.73 0.83 72.6%
B2 B2 0.42 0.19 0.14 0.76 0.64 0.68 0.72 0.82 72.5%
B3 B3 0.04 0.02 0.06 0.57 0.62 0.67 0.79 62.2%
0.71 0.32 0.00 0.17 1.20 71.9%
59.4% 26.7% 0.0% 13.9% 100.0%
2.15 1.34 1.01 0.35 4.85 0.61 0.65 0.80 69.6%
44.4% 27.6% 20.8% 7.2% 100.0%
Calculations assume Type C soils per NRCS
SF-1
RUNOFF COEFFICIENTS - DEVELOPED
PROJECT NAME: 10/1/2013
PROJECT NUMBER:
CALCULATED BY:
CHECKED BY:
TOTAL
STUDY
AREA
Basin A
SUBTOTAL
Basin B
SUBTOTAL
12026_TLE SF-1, 2 and 3 Developed_FINAL Page 2 of 8
The Learning Experience at Miramont DATE:
12026
RAO
MDC
FINAL
tc
DESIGN AREA C5 LENGTH SLOPE T
i LENGTH SLOPE Cv
Land Surface VEL Tt COMP. TOTAL tc=(L/180)+10 C2 C100
BASIN Ac Ft % Min. Ft. % fps Min. tc LENGTH Min. Min.
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15)
A1 2.26 0.67 211 1.1% 11.0 288 1.0% 20.0 Paved Areas 2.0 2.4 13.4 499 12.8 13.4 0.64 0.71
A2 0.65 0.77 180 2.0% 6.5 16 1.5% 20.0 Paved Areas 2.4 0.1 6.6 196 11.1 6.6 0.74 0.80
A3 0.21 0.18 22 25.0% 2.7 2.7 22 10.1 5.0 0.07 0.27
A4 0.13 0.21 43 2.0% 8.4 8.4 43 10.2 8.4 0.11 0.31
A5 0.11 0.75 120 2.0% 5.6 5.6 120 10.7 5.6 0.73 0.77
A6 0.11 0.75 120 2.0% 5.6 5.6 120 10.7 5.6 0.73 0.77
A7 0.18 0.51 92 2.0% 8.2 8.2 92 10.5 8.2 0.46 0.56
B1 0.38 0.69 20 2.0% 2.7 102 2.9% 20.0 Paved Areas 3.4 0.5 3.2 122 10.7 5.0 0.65 0.73
B2 0.76 0.68 10 2.0% 1.9 720 0.5% 20.0 Paved Areas 1.4 8.5 10.4 730 14.1 10.4 0.64 0.72
B3 0.06 0.62 90 2.0% 6.7 200 0.9% 20.0 Paved Areas 1.9 1.8 8.5 290 11.6 8.5 0.57 0.67
STANDARD FORM SF-2 - DEVELOPED
tc CHECK
(URBANIZED BASINS)
PROJECT NAME:
PROJECT NUMBER:
CALCULATED BY:
CHECKED BY:
Time of Concentration
10/1/2013
SUB-BASIN
DATA
INITIAL
TIME (Ti)
TRAVEL TIME
(Tt)
1 / 3
0 . 395 ( 1 . 1 ) 1 / 2
S
Ti C L
−
= T
L
t = 60 V
PROJECT NAME: The Learning Experience at Miramont DATE:
PROJECT NUMBER: 12026 P1 (1-Hour Rainfall)
= 0.82
CALCULATED BY: RAO
CHECKED BY: MDC
REMARKS
DESIGN
POINT
DESIGN
BASIN
AREA
(AC)
RUNOFF
COEFF C2
tc (min)
C*A(ac)
I
(in/hr)
Q
(cfs)
tc(min)
S(C*A)
(ac)
I
(in/hr)
Q
(cfs)
SLOPE
(%)
STREET
FLOW(cfs)
DESIGN
FLOW(cfs)
SLOPE
(%)
PIPE
SIZE (in)
LENGTH
(ft)
VELOCITY
(fps)
tt
(min)
(2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20) (21) (22)
B1 B1 0.38 0.65 5.00
A4 A4 0.13 0.11
A7 A7
2.70
0.19
0.07 5.00 0.02 2.78
A4
STANDARD FORM SF-3 - DEVELOPED
STORM DRAINAGE DESIGN - RATIONAL METHOD 2 YEAR EVENT
10/1/2013
TOTAL RUNOFF STREET PIPE TRAVEL TIME
(1)
Inlet 1-2 A1 A1
STORM
LINE
DIRECT RUNOFF
PROJECT NAME: The Learning Experience at Miramont DATE:
PROJECT NUMBER: 12026 P1 (1-Hour Rainfall)
= 1.4
CALCULATED BY: RAO
CHECKED BY: MDC
REMARKS
DESIGN
POINT
DESIGN
BASIN
AREA
(AC)
RUNOFF
COEFF C2
tc (min)
C*A(ac)
I
(in/hr)
Q
(cfs)
tc(min)
S(C*A)
(ac)
I
(in/hr)
Q
(cfs)
SLOPE
(%)
STREET
FLOW(cfs)
DESIGN
FLOW(cfs)
SLOPE
(%)
PIPE
SIZE (in)
LENGTH
(ft)
VELOCITY
(fps)
tt
(min)
(2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20) (21) (22)
B3 B3
0.06 0.57 8.47
0.49 3.73 1.81
0.04 4.03 0.15
B2 B2 0.76 0.64 10.42
B1 B1 0.38 0.65 5.00 0.25 4.75 1.17
A3 A3 0.21 0.27 5.00 0.06
4.61 0.39
4.75 0.28
A5 A5 0.11 0.77 5.58 0.08 4.61 0.39
A6 A6 0.11 0.77 5.58 0.08
Sum of A2 and A7 (Inlet 1-1) A2 8.2 0.62 4.08 2.51
8.22 0.10 4.08 0.41
A2 A2 0.65 0.80 6.58 0.52 4.39 2.26
A7 A7 0.18 0.56
Sum on A1 and A4 A4 13.4 1.65 3.35 5.53
PROJECT NAME: The Learning Experience at Miramont DATE:
PROJECT NUMBER: 12026 P1 (1-Hour Rainfall) = 2.86
CALCULATED BY: RAO
CHECKED BY: MDC
REMARKS
DESIGN
POINT
DESIGN
BASIN
AREA
(AC)
RUNOFF
COEFF C100
tc (min)
C*A(ac)
I
(in/hr)
Q
(cfs)
tc(min)
S(C*A)
(ac)
I
(in/hr)
Q
(cfs)
SLOPE
(%)
STREET
FLOW(cfs)
DESIGN
FLOW(cfs)
SLOPE
(%)
PIPE
SIZE (in)
LENGTH
(ft)
VELOCITY
(fps)
tt
(min)
(2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20) (21) (22)
0.05 0.42
0.62 7.61 4.71
8.24
9.70
0.11 9.70 1.07
0.86
3.05
0.86
8.2 0.69 8.33 5.73
1.04
A4 A4 0.13 0.54 8.45 0.07
1.83 6.84 12.50
A4
5.05
13.4 1.90 6.84 12.99
STANDARD FORM SF-3 - DEVELOPED
STORM DRAINAGE DESIGN - RATIONAL METHOD 100 YEAR EVENT
41
Table RO-11
Rational Method Runoff Coefficients for Composite Analysis
Character of Surface Runoff Coefficient
Streets, Parking Lots,
Drives:
Asphalt 0.95
Concrete 0.95
Gravel 0.5
Roofs 0.95
Recycled Asphalt 0.8
Lawns, Sandy Soil:
Flat <2% 0.1
Average 2 to 7% 0.15
Steep >7% 0.2
Lawns, Heavy Soil:
Flat <2% 0.2
Average 2 to 7% 0.25
Steep >7% 0.35
(4) A new Section 2.9 is added, to read as follows:
2.9 Composite Runoff Coefficient
Drainage sub-basins are frequently composed of land that has multiple surfaces 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
i i
A
C A
C
∑
= = 1
*
(RO-8)
Where: C = Composite Runoff Coefficient
Ci = Runoff Coefficient for Specific Area (Ai)
Ai = Area of Surface with Runoff Coefficient of Ci, acres or feet2
n = Number of different surfaces to be considered
At = Total Area over which C is applicable, acres or feet2
(5) A new Section 2.10 is added, to read as follows:
42
2.10 Runoff Coefficient Adjustment for Infrequent Storms
The runoff coefficients provided in tables RO-10 and RO-11 are appropriate for use with
the 2-year storm event. For storms with higher intensities, an adjustment of the runoff
coefficient is required due to the lessening amount of infiltration, depression retention,
evapo-transpiration and other losses that have a proportionally smaller effect on storm
runoff. This adjustment is applied to the composite runoff coefficient.
These frequency adjustment factors are found in Table RO-12.
Table RO-12
Rational Method Runoff Coefficients for Composite Analysis
Storm Return Period
(years)
Frequency Factor
Cf
2 to 10
11 to 25
26 to 50
51 to 100
1.00
1.10
1.20
1.25
Note: The product of C times Cf cannot exceed the value of 1, in the cases where it does a value of
1 must be used
(6) Section 3.1 is deleted in its entirety.
(7) Section 3.2 is deleted in its entirety.
(8) Section 3.3 is deleted in its entirety.
(9) A new Section 4.3 is added, to read as follows:
4.3 Computer Modeling Practices
(a) For circumstances requiring computer modeling, the design storm hydrographs must
be determined using the Stormwater Management Model (SWMM). Basin and
conveyance element parameters must be computed based on the physical characteristics
of the site.
(b) Refer to the SWMM Users’ Manual for appropriate modeling methodology, practices
and development. The Users’ Manual can be found on the Environmental Protection
Agency (EPA) website (http://www.epa.gov/ednnrmrl/models/swmm/index.htm).
(c) It is the responsibility of the design engineer to verify that all of the models used in
the design meet all current City criteria and regulations.
4.3.1 Surface Storage, Resistance Factors, and Infiltration
Table RO-13 provides values for surface storage for pervious and impervious surfaces
and the infiltration rates to be used with SWMM. Table RO-13 also lists the appropriate
infiltration decay rate, zero detention depth and resistance factors, or Manning’s “n”
values, for pervious and impervious surfaces to be used for SWMM modeling in the city
of Fort Collins.
33
(11) Section 4.0 is amended to read as follows:
4.0 Intensity-Duration-Frequency Curves for Rational Method:
The one-hour rainfall Intensity-Duration-Frequency tables for use the Rational Method
of runoff analysis are provided in Table RA-7 and in Table RA-8.
Table RA-7 -- City of Fort Collins
Rainfall Intensity-Duration-Frequency Table
for Use with the Rational Method
(5 minutes to 30 minutes)
2-Year 10-Year 100-Year
Duration
(min)
Intensity
(in/hr)
Intensity
(in/hr)
Intensity
(in/hr)
5 2.85 4.87 9.95
6 2.67 4.56 9.31
7 2.52 4.31 8.8
8 2.4 4.1 8.38
9 2.3 3.93 8.03
10 2.21 3.78 7.72
11 2.13 3.63 7.42
12 2.05 3.5 7.16
13 1.98 3.39 6.92
14 1.92 3.29 6.71
15 1.87 3.19 6.52
16 1.81 3.08 6.3
17 1.75 2.99 6.1
18 1.7 2.9 5.92
19 1.65 2.82 5.75
20 1.61 2.74 5.6
21 1.56 2.67 5.46
22 1.53 2.61 5.32
23 1.49 2.55 5.2
24 1.46 2.49 5.09
25 1.43 2.44 4.98
26 1.4 2.39 4.87
27 1.37 2.34 4.78
28 1.34 2.29 4.69
29 1.32 2.25 4.6
30 1.3 2.21 4.52
34
Table RA-8 -- City of Fort Collins
Rainfall Intensity-Duration-Frequency Table
for Use with the Rational Method
(31 minutes to 60 minutes)
2-Year 10-Year 100-Year
Duration
(min)
Intensity
(in/hr)
Intensity
(in/hr)
Intensity
(in/hr)
31 1.27 2.16 4.42
32 1.24 2.12 4.33
33 1.22 2.08 4.24
34 1.19 2.04 4.16
35 1.17 2.0 4.08
36 1.15 1.96 4.01
37 1.16 1.93 3.93
38 1.11 1.89 3.87
39 1.09 1.86 3.8
40 1.07 1.83 3.74
41 1.05 1.8 3.68
42 1.04 1.77 3.62
43 1.02 1.74 3.56
44 1.01 1.72 3.51
45 0.99 1.69 3.46
46 0.98 1.67 3.41
47 0.96 1.64 3.36
48 0.95 1.62 3.31
49 0.94 1.6 3.27
50 0.92 1.58 3.23
51 0.91 1.56 3.18
52 0.9 1.54 3.14
53 0.89 1.52 3.1
54 0.88 1.5 3.07
55 0.87 1.48 3.03
56 0.86 1.47 2.99
57 0.85 1.45 2.96
58 0.84 1.43 2.92
59 0.83 1.42 2.89
60 0.82 1.4 2.86
Final Drainage Report for The Learning Experience at Miramont Office Park
15
Appendix C - Hydraulic Calculations
12026 UD-Inlet_v3.12 2013-06-21, Inlet In Sump 6/21/2013, 3:39 PM
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 = 2 2
Water Depth at Flowline (outside of local depression) Ponding Depth = 6.0 6.0 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) Qa
= 10.5 10.5 cfs
Inlet Capacity IS GOOD for Minor and Major Storms (>Q PEAK) Q PEAK REQUIRED = 1.8 6.6 cfs
INLET IN A SUMP OR SAG LOCATION
TLE Miramont #12026
Inlet 1-1
CDOT Type R Curb Opening
H-Vert
H-Curb
W
Lo (C)
Lo (G)
Wo
WP
Override Depths
12026 Inlet 1-2 UD-Inlet_v3.12 2013-06-21, Inlet In Sump 6/21/2013, 3:43 PM
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 = 3 3
Water Depth at Flowline (outside of local depression) Ponding Depth = 4.0 6.2 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) Qa
= 3.9 14.4 cfs
Inlet Capacity IS GOOD for Minor and Major Storms (>Q PEAK) Q PEAK REQUIRED = 3.9 14.4 cfs
INLET IN A SUMP OR SAG LOCATION
TLE Miramont #12026
Inlet 1-2 (Basin A1)
CDOT Type R Curb Opening
H-Vert
H-Curb
W
Lo (C)
Lo (G)
Wo
WP
Override Depths
Project:
Basin ID:
Design Information (Input): Design Information (Input):
Catchment Drainage Imperviousness Ia = 68.80 percent Catchment Drainage Imperviousness Ia = 68.80 percent
Catchment Drainage Area A = 3.650 acres Catchment Drainage Area A = 3.650 acres
Predevelopment NRCS Soil Group Type = C A, B, C, or D Predevelopment NRCS Soil Group Type = C A, B, C, or D
Return Period for Detention Control T = 10 years (2, 5, 10, 25, 50, or 100) Return Period for Detention Control T = 100 years (2, 5, 10, 25, 50, or 100)
Time of Concentration of Watershed Tc = 13 minutes Time of Concentration of Watershed Tc = 13 minutes
Allowable Unit Release Rate q = 0.20 cfs/acre Allowable Unit Release Rate q = 0.50 cfs/acre
One-hour Precipitation P1 = 1.40 inches One-hour Precipitation P1 = 2.86 inches
Design Rainfall IDF Formula i = C1* P1/(C2+Tc)^C3 Design Rainfall IDF Formula i = C1* P1/(C2+Tc)^C3
Coefficient One C1 = 28.50 Coefficient One C1 = 28.50
Coefficient Two C2 = 10 Coefficient Two C2 = 10
Coefficient Three C3 = 0.789 Coefficient Three C3 = 0.789
Determination of Average Outflow from the Basin (Calculated): Determination of Average Outflow from the Basin (Calculated):
Runoff Coefficient C = 0.68 Runoff Coefficient C = 0.79
Inflow Peak Runoff Qp-in = 9.10 cfs Inflow Peak Runoff Qp-in = 21.59 cfs
Allowable Peak Outflow Rate Qp-out = 0.73 cfs Allowable Peak Outflow Rate Qp-out = 1.83 cfs
Mod. FAA Minor Storage Volume = 14,381 cubic feet Mod. FAA Major Storage Volume = 27,036 cubic feet
Mod. FAA Minor Storage Volume = 0.330 acre-ft Mod. FAA Major Storage Volume = 0.621 acre-ft
5 <- Enter Rainfall Duration Incremental Increase Value Here (e.g. 5 for 5-Minutes)
Rainfall Rainfall Inflow Adjustment Average Outflow Storage Rainfall Rainfall Inflow Adjustment Average Outflow Storage
Duration Intensity Volume Factor Outflow Volume Volume Duration Intensity Volume Factor Outflow Volume Volume
minutes inches / hr acre-feet "m" cfs acre-feet acre-feet minutes inches / hr acre-feet "m" cfs acre-feet acre-feet
(input) (output) (output) (output) (output) (output) (output) (input) (output) (output) (output) (output) (output) (output)
0 0.00 0.000 0.00 0.00 0.000 0.000 0 0.00 0.000 0.00 0.00 0.000 0.000
5 4.71 0.081 1.00 0.73 0.005 0.075 5 9.62 0.191 1.00 1.83 0.013 0.179
10 3.75 0.128 1.00 0.73 0.010 0.118 10 7.67 0.305 1.00 1.83 0.025 0.279
15 3.15 0.161 0.93 0.68 0.014 0.147 15 6.43 0.383 0.93 1.70 0.035 0.348
20 2.73 0.186 0.83 0.60 0.017 0.170 20 5.57 0.442 0.83 1.51 0.041 0.401
25 2.41 0.206 0.76 0.55 0.019 0.187 25 4.93 0.490 0.76 1.39 0.048 0.442
30 2.17 0.223 0.72 0.52 0.022 0.201 30 4.44 0.529 0.72 1.31 0.054 0.475
35 1.98 0.237 0.69 0.50 0.024 0.213 35 4.04 0.562 0.69 1.25 0.060 0.502
40 1.82 0.249 0.66 0.48 0.027 0.222 40 3.72 0.591 0.66 1.21 0.067 0.525
45 1.69 0.260 0.64 0.47 0.029 0.231 45 3.45 0.617 0.64 1.18 0.073 0.544
50 1.58 0.270 0.63 0.46 0.032 0.238 50 3.22 0.640 0.63 1.15 0.079 0.561
55 1.48 0.278 0.62 0.45 0.034 0.244 55 3.03 0.661 0.62 1.13 0.085 0.575
60 1.40 0.287 0.61 0.44 0.037 0.250 60 2.85 0.680 0.61 1.11 0.092 0.588
65 1.32 0.294 0.60 0.44 0.039 0.255 65 2.70 0.698 0.60 1.10 0.098 0.600
70 1.26 0.301 0.59 0.43 0.042 0.259 70 2.57 0.714 0.59 1.08 0.104 0.610
75 1.20 0.307 0.59 0.43 0.044 0.263 75 2.45 0.729 0.59 1.07 0.111 0.619
80 1.15 0.313 0.58 0.42 0.047 0.267 80 2.34 0.744 0.58 1.06 0.117 0.627
85 1.10 0.319 0.58 0.42 0.049 0.270 85 2.24 0.757 0.58 1.05 0.123 0.634
90 1.05 0.324 0.57 0.42 0.052 0.273 90 2.15 0.770 0.57 1.04 0.129 0.640
95 1.01 0.329 0.57 0.41 0.054 0.275 95 2.07 0.782 0.57 1.04 0.136 0.646
100 0.98 0.334 0.57 0.41 0.057 0.278 100 2.00 0.793 0.57 1.03 0.142 0.651
105 0.94 0.339 0.56 0.41 0.059 0.280 105 1.93 0.804 0.56 1.03 0.148 0.656
110 0.91 0.343 0.56 0.41 0.062 0.282 110 1.87 0.815 0.56 1.02 0.155 0.660
115 0.88 0.348 0.56 0.41 0.064 0.283 115 1.81 0.825 0.56 1.02 0.161 0.664
120 0.86 0.352 0.55 0.40 0.067 0.285 120 1.75 0.835 0.55 1.01 0.167 0.667
125 0.83 0.356 0.55 0.40 0.069 0.286 125 1.70 0.844 0.55 1.01 0.173 0.670
130 0.81 0.359 0.55 0.40 0.072 0.287 130 1.65 0.853 0.55 1.00 0.180 0.673
135 0.79 0.363 0.55 0.40 0.074 0.289 135 1.61 0.861 0.55 1.00 0.186 0.675
140 0.77 0.366 0.55 0.40 0.077 0.290 140 1.56 0.870 0.55 1.00 0.192 0.677
145 0.75 0.370 0.54 0.40 0.079 0.290 145 1.52 0.878 0.54 0.99 0.199 0.679
150 0.73 0.373 0.54 0.40 0.082 0.291 150 1.49 0.886 0.54 0.99 0.205 0.681
155 0.71 0.376 0.54 0.40 0.084 0.292 155 1.45 0.893 0.54 0.99 0.211 0.682
160 0.69 0.379 0.54 0.39 0.087 0.292 160 1.42 0.901 0.54 0.99 0.217 0.683
165 0.68 0.382 0.54 0.39 0.089 0.293 165 1.39 0.908 0.54 0.98 0.224 0.684
170 0.66 0.385 0.54 0.39 0.092 0.293 170 1.35 0.915 0.54 0.98 0.230 0.685
12026 UD-Detention_v2.32 FINAL, Basin 10/1/2013, 2:09 PM
Project:
Basin ID:
Design Information (Input):
Width of Basin Bottom, W = ft Right Triangle OR…
Length of Basin Bottom, L = ft Isosceles Triangle OR…
Dam Side-slope (H:V), Zd = ft/ft Rectangle OR…
Circle / Ellipse OR…
Irregular (Use Overide values in cells G32:G52)
MINOR MAJOR
Storage Requirement from Sheet 'Modified FAA': 0.27 0.62 acre-ft.
Stage-Storage Relationship: Storage Requirement from Sheet 'Hydrograph': acre-ft.
Storage Requirement from Sheet 'Full-Spectrum': acre-ft.
Labels Water Side Basin Basin Surface Surface Volume Surface Volume Target Volumes
for WQCV, Minor, Surface Slope Width at Length at Area at Area at Below Area at Below for WQCV, Minor,
& Major Storage Elevation (H:V) Stage Stage Stage Stage Stage Stage Stage & Major Storage
Stages ft ft/ft ft ft ft2 ft2 User ft3 acres acre-ft Volumes
(input) (input) Below El. (output) (output) (output) Overide (output) (output) (output) (for goal seek)
4997.00 (input) 0 0.000 0.000
4998.00 0.00 0.00 3,396 1,698 0.078 0.039
WQCV 4999.00 0.00 0.00 6,177 6,485 0.142 0.149 WCQV = 0.098
4999.50 0.00 0.00 6,368 9,621 0.146 0.221
5000.00 0.00 0.00 6,575 12,857 0.151 0.295
Minor 5000.90 0.00 0.00 6,923 18,931 0.159 0.435 10 YEAR = .43
5001.00 0.00 0.00 6,967 19,625 0.160 0.451
5002.00 0.00 0.00 7,747 26,982 0.178 0.619
Major 5002.59 0.00 0.00 11,541 32,672 0.265 0.750 100 YEAR = .719
5003.60 0.00 0.00 11,541 44,328 0.265 1.018
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
#N/A #N/A
12026 UD-Detention_v2.32 FINAL, Basin 10/1/2013, 2:09 PM
Project:
Basin ID:
STAGE-STORAGE SIZING FOR DETENTION BASINS
4997.08
4998.08
4999.08
5000.08
5001.08
5002.08
5003.08
5004.08
0.00 0.20 0.40 0.60 0.80 1.00 1.20
Stage (ft. elev.)
Storage (acre-feet)
STAGE-STORAGE CURVE FOR THE POND
12026 UD-Detention_v2.32 FINAL, WQCV 10/1/2013, 2:09 PM
Project:
Basin ID:
WQCV Design Volume (Input):
Catchment Imperviousness, Ia = 68.8 percent Diameter of holes, D = 0.562 in. Time to Drain the Pond = 40 hours
Catchment Area, A = 3.65 acres Number of holes per row, N = 1
Depth at WQCV outlet above lowest perforation, H = 2 feet OR
Vertical distance between rows, h = 4.00 inches
Number of rows, NL = 5 Height of slot, H = in.
Orifice discharge coefficient, Co = 0.60 Width of slot, W = in.
Slope of Basin Trickle Channel, S = 0.010 ft / ft
Outlet Design Information (Output):
Water Quality Capture Volume (1.0 * (0.91 * I^3 - 1.19 * I^2 + 0.78 * I)), WQCV = 0.270 watershed inches
Water Quality Capture Volume (WQCV) = 0.082 acre-feet 1.63
Design Volume (WQCV / 12 * Area * 1.2) Vol = 0.098 acre-feet
Outlet area per row, Ao = 0.25 square inches
Total opening area at each row based on user-input above, Ao = 0.25 square inches
Total opening area at each row based on user-input above, Ao = 0.002 square feet
Calculation of Collection Capacity:
Stage Row 1 Row 2 Row 3 Row 4 Row 5 Row 6 Row 7 Row 8 Row 9 Row 10 Row 11 Row 12 Row 13 Row 14 Row 15 Row 16 Row 17 Row 18 Row 19 Row 20 Row 21 Row 22 Row 23 Row 23 Σ
ft 4997.45 4997.78 4998.12 4998.45 4998.78 Flow
(input)
4997.00 0.0000 0.0000 0.0000 0.0000 0.0000 0.00
4997.50 0.0019 0.0000 0.0000 0.0000 0.0000 0.00
4998.00 0.0061 0.0039 0.0000 0.0000 0.0000 0.01
4998.50 0.0085 0.0070 0.0051 0.0019 0.0000 0.02
4999.00 0.0103 0.0092 0.0078 0.0061 0.0039 0.04
4999.50 0.0119 0.0109 0.0097 0.0085 0.0070 0.05
5000.00 0.0132 0.0124 0.0114 0.0103 0.0092 0.06
5000.50 0.0145 0.0137 0.0128 0.0119 0.0109 0.06
5001.00 0.0156 0.0149 0.0141 0.0132 0.0124 0.07
5001.50 0.0167 0.0160 0.0152 0.0145 0.0137 0.08
5002.00 0.0177 0.0170 0.0163 0.0156 0.0149 0.08
5002.50 0.0186 0.0180 0.0174 0.0167 0.0160 0.09
5003.00 0.0195 0.0189 0.0183 0.0177 0.0170 0.09
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
12026 UD-Detention_v2.32 FINAL, WQCV 10/1/2013, 2:09 PM
Worksheet Protected
Project:
Basin ID:
STAGE-DISCHARGE SIZING OF THE WATER QUALITY CAPTURE VOLUME (WQCV) OUTLET
TLE at Miramont #12026
5000.00
5000.50
5001.00
5001.50
5002.00
5002.50
5003.00
5003.50
0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 0.10
Stage (feet, elev.)
Discharge (cfs)
STAGE-DISCHARGE CURVE FOR THE WQCV OUTLET STRUCTURE
12026 UD-Detention_v2.32 FINAL, Restrictor Plate 10/1/2013, 2:09 PM
Project:
Basin ID:
X
1
#1 Vertical #2 Vertical
Sizing the Restrictor Plate for Circular Vertical Orifices or Pipes (Input) Orifice Orifice
Water Surface Elevation at Design Depth Elev: WS = 5,002.59 feet
Pipe/Vertical Orifice Entrance Invert Elevation Elev: Invert = 4,996.97 feet
Required Peak Flow through Orifice at Design Depth Q = 1.83 1.83 cfs
Pipe/Vertical Orifice Diameter (inches) Dia = 12.0 12.0 inches
Orifice Coefficient Co = 0.65 0.65
Full-flow Capacity (Calculated)
Full-flow area Af = 0.79 sq ft
Half Central Angle in Radians Theta = 3.14 rad
Full-flow capacity Qf = 9.3 cfs
Percent of Design Flow = 508%
Calculation of Orifice Flow Condition
Half Central Angle (0<Theta<3.1416) Theta = 1.04 rad
Flow area Ao = 0.15 sq ft
Top width of Orifice (inches) To = 10.32 inches
Height from Invert of Orifice to Bottom of Plate (feet) Yo = 0.25 feet
Elevation of Bottom of Plate Elev Plate Bottom Edge = 4,997.22 feet
Resultant Peak Flow Through Orifice at Design Depth Qo = 1.8 cfs
Width of Equivalent Rectangular Vertical Orifice Equivalent Width = 0.60 feet
Centroid Elevation of Equivalent Rectangular Vertical Orifice Equiv. Centroid El. = 4,997.10 feet
TLE at Miramont #12026
RESTRICTOR PLATE SIZING FOR CIRCULAR VERTICAL ORIFICES
12026 UD-Detention_v2.32 FINAL, Outlet 10/1/2013, 2:09 PM
Project:
Basin ID:
Design Information (Input): #1 Horiz. #2 Horiz. #1 Vert. #2 Vert.
Circular Opening: Diameter in Inches Dia. = 4.27 inches
OR
Rectangular Opening: Width in Feet W = 2.92 0.60 ft.
Length (Height for Vertical) L or H = 2.92 0.25 ft.
Percentage of Open Area After Trash Rack Reduction % open = 50 100 100 %
Orifice Coefficient Co = 0.65 0.65 0.65
Weir Coefficient Cw = 3.00
Orifice Elevation (Bottom for Vertical) Eo = 5000.90 4,999.00 4,996.97 ft.
Calculation of Collection Capacity:
Net Opening Area (after Trash Rack Reduction) Ao = 4.26 0.10 0.15 sq. ft.
OPTIONAL: User-Overide Net Opening Area Ao = sq. ft.
Perimeter as Weir Length Lw = 8.76 ft.
OPTIONAL: User-Overide Weir Length Lw = ft.
Top Elevation of Vertical Orifice Opening, Top = 4999.36 4997.22 ft.
Center Elevation of Vertical Orifice Opening, Cen = 4999.18 4997.10 ft.
Horizontal Orifices Vertical Orifices
Labels Water WQCV #1 Horiz. #1 Horiz. #2 Horiz. #2 Horiz. #1 Vert. #2 Vert. Total Target Volumes
for WQCV, Minor, Surface Plate/Riser Weir Orifice Weir Orifice Collection Collection Collection for WQCV, Minor,
& Major Storage Elevation Flow Flow Flow Flow Flow Capacity Capacity Capacity & Major Storage
W.S. Elevations ft cfs cfs cfs cfs cfs cfs cfs cfs Volumes
(input) (linked) (User-linked) (output) (output) (output) (output) (output) (output) (output) (link for goal seek)
4997.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.00
4998.00 0.00 0.00 0.00 0.00 0.00 0.00 0.74 0.00
WQCV 4999.00 0.01 0.00 0.00 0.00 0.00 0.00 1.08 0.01 wqcv
4999.50 0.02 0.00 0.00 0.00 0.00 0.29 1.21 0.32
5000.00 0.04 0.00 0.00 0.00 0.00 0.47 1.33 0.51
Minor 5000.90 0.05 0.00 0.00 0.00 0.00 0.68 1.53 0.73 10 year
5001.00 0.06 0.83 7.03 0.00 0.00 0.70 1.55 1.55
5002.00 0.06 30.32 23.32 0.00 0.00 0.87 1.73 1.73
Major 5002.59 0.07 57.74 28.91 0.00 0.00 0.96 1.83 1.83 spillway/100 yr
5003.60 0.08 116.59 36.54 0.00 0.00 1.09 2.00 2.00
0.08 #N/A #N/A #N/A #N/A #N/A #N/A #N/A
0.09 #N/A #N/A #N/A #N/A #N/A #N/A #N/A
0.09 #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
12026 UD-Detention_v2.32 FINAL, Outlet 10/1/2013, 2:09 PM
Project:
Basin ID:
TLE at Miramont #12026
STAGE-DISCHARGE SIZING OF THE WEIRS AND ORIFICES (INLET CONTROL)
4997.08
4998.08
4999.08
5000.08
5001.08
5002.08
5003.08
5004.08
0 0.5 1 1.5 2 2.5
Stage (feet, elev.)
Discharge (cfs)
STAGE-DISCHARGE CURVE FOR THE OUTLET STRUCTURE
12026 UD-Detention_v2.32 FINAL, Spillway 10/1/2013, 2:09 PM
Project:
Basin ID:
75.96
4.00000
Design Information (input):
Bottom Length of Weir L = 6.00 feet
Angle of Side Slope Weir Angle = 75.96 degrees
Elev. for Weir Crest EL. Crest = 5,002.59 feet
Coef. for Rectangular Weir Cw = 3.30
Coef. for Trapezoidal Weir Ct = 2.50
Calculation of Spillway Capacity (output):
Water Rect. Triangle Total Total
Surface Weir Weir Spillway Pond
Elevation Flowrate Flowrate Release Release
ft. cfs cfs cfs cfs
(linked) (output) (output) (output) (output)
4997.00 0.00 0.00 0.00 0.00
4998.00 0.00 0.00 0.00 0.00
4999.00 0.00 0.00 0.00 0.01
4999.50 0.00 0.00 0.00 0.32
5000.00 0.00 0.00 0.00 0.51
5000.90 0.00 0.00 0.00 0.73
5001.00 0.00 0.00 0.00 1.55
5002.00 0.00 0.00 0.00 1.73
5002.59 0.00 0.00 0.00 1.83
5003.60 20.10 10.25 30.35 32.35
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A
12026 UD-Detention_v2.32 FINAL, Spillway 10/1/2013, 2:09 PM
Project:
Basin ID:
STAGE-DISCHARGE SIZING OF THE SPILLWAY
TLE at Miramont
Existing Spillway Capacity
0 0.2 0.4 0.6 0.8 1 1.2
4997
4998
4999
5000
5001
5002
5003
5004
0 5 10 15 20 25 30 35
Storage (Acre-Feet)
Stage (feet, elev.)
Pond Discharge (cfs)
STAGE-STORAGE-DISCHARGE CURVES FOR THE POND
TOTAL DISCHARGE SPILLWAY DISCHARGE POND STORAGE
UD-BMP for Basin 1 and 4, EDB 7/8/2013, 3:42 PM
Sheet 1 of 4
Designer:
Company:
Date:
Project:
Location:
1. Basin Storage Volume
A) Effective Imperviousness of Tributary Area, Ia I
a = 69.7 %
B) Tributary Area's Imperviousness Ratio (i = Ia / 100 ) i = 0.697
C) Contributing Watershed Area Area = 2.390 ac
D) For Watersheds Outside of the Denver Region, Depth of Average d6 = in
Runoff Producing Storm
E) Design Concept
(Select EURV when also designing for flood control)
F) Design Volume (1.2 WQCV) Based on 40-hour Drain Time VDESIGN
= 0.065 ac-ft
(VDESIGN = (1.0 * (0.91 * i
3
- 1.19 * i
2
+ 0.78 * i) / 12 * Area * 1.2)
G) For Watersheds Outside of the Denver Region, VDESIGN OTHER
= ac-ft
Water Quality Capture Volume (WQCV) Design Volume
(VWQCV OTHER = (d
6*(VDESIGN
/0.43))
H) User Input of Water Quality Capture Volume (WQCV) Design Volume VDESIGN USER
= ac-ft
(Only if a different WQCV Design Volume is desired)
I) Predominant Watershed NRCS Soil Group
J) Excess Urban Runoff Volume (EURV) Design Volume
For HSG A: EURVA = (0.1878i - 0.0104)*Area EURV = ac-f t
For HSG B: EURVB = (0.1178i - 0.0042)*Area
For HSG C/D: EURVC/D = (0.1043i - 0.0031)*Area
2. Basin Shape: Length to Width Ratio L : W = 2.0 : 1
(A basin length to width ratio of at least 2:1 will improve TSS reduction.)
3. Basin Side Slopes
A) Basin Maximum Side Slopes Z = 4.00 ft / ft
(Horizontal distance per unit vertical, 4:1 or flatter preferred)
4. Inlet
A) Describe means of providing energy dissipation at concentrated
inflow locations:
Design Procedure Form: Extended Detention Basin (EDB)
TLE Miramont
Redland
July 8, 2013
Basin 1 and 4 Forebay Design
TJF
Choose One
Excess Urban Runoff Volume (EURV)
Choose One
A
B
C / D
Water Quality Capture Volume (WQCV)
UD-BMP for Basin 1 and 4, EDB 7/8/2013, 3:42 PM
Sheet 2 of 4
Designer:
Company:
Date:
Project:
Location:
5. Forebay
A) Minimum Forebay Volume VFMIN
= 0.001 ac-ft
(VFMIN = 1% of the WQCV)
B) Actual Forebay Volume VF
= ac-ft
C) Forebay Depth DF
= 6.0 in
(DF = 12 inch maximum)
D) Forebay Discharge
i) Undetained 100-year Peak Discharge Q100
= 14.74 cfs
ii) Forebay Discharge Design Flow QF
= 0.29 cfs
(QF = 0.02 * Q
100)
E) Forebay Discharge Design
F) Discharge Pipe Size (minimum 8-inches) Calculated DP = in
G) Rectangular Notch Width Calculated WN
= 4.2 in
6. Trickle Channel
A) Type of Trickle Channel
F) Slope of Trickle Channel S = ft / ft
7. Micropool and Outlet Structure
A) Depth of Micropool (2.5-feet minimum) DM
= ft
B) Surface Area of Micropool (10 ft
2
minimum) A
M = sq ft
C) Outlet Type
D) Depth of Design Volume (EURV or 1.2 WQCV) Based on the Design H = feet
Concept Chosen Under 1.E.
E) Volume to Drain Over Prescribed Time WQCV = ac-ft
F) Drain Time TD
= hours
(Min TD for WQCV= 40 hours; Max T
D for EURV= 72 hours)
G) Recommended Maximum Outlet Area per Row, (Ao) A
o = square inches
H) Orifice Dimensions:
i) Circular Orifice Diameter or Dorifice
= inches
ii) Width of 2" High Rectangular Orifice Worifice
= inches
I) Number of Columns nc
= number
J) Actual Design Outlet Area per Row (Ao) A
o = square inches
K) Number of Rows (nr) nr
= number
L) Total Outlet Area (Aot) A
ot = square inches
UD-BMP for Basin 1 and 4, EDB 7/8/2013, 3:42 PM
Sheet 3 of 4
Designer:
Company:
Date:
Project:
Location:
8. Initial Surcharge Volume
A) Depth of Initial Surcharge Volume DIS
= in
(Minimum recommended depth is 4 inches)
B) Minimum Initial Surcharge Volume VIS = cu ft
(Minimum volume of 0.3% of the WQCV)
C) Initial Surcharge Provided Above Micropool Vs= cu ft
9. Trash Rack
A) Type of Water Quality Orifice Used
B) Water Quality Screen Open Area: At = 38.5*(e
-0.095D
)*Aot
At = square inches
C) For 2", or Smaller, Circular Opening (See Fact Sheet T-12):
i) Width of Water Quality Screen and Concrete Opening (Wopening) W
opening = inches
ii) Height of Water Quality Screen (HTR) H
TR = inches
iii) Type of Screen, Describe if "Other"
D) For 2" High Rectangular Opening:
i) Width of Rectangular Opening (Worifice) W = inches
ii) Width of Water Quality Screen Opening (Wopening) W
opening = ft
iii) Height of Water Quality Screen (HTR) H
TR = ft
iv) Type of Screen, Describe if "Other"
v) Cross-bar Spacing inches
vi) Minimum Bearing Bar Size
Design Procedure Form: Extended Detention Basin (EDB)
July 8, 2013
TLE Miramont
Basin 1 and 4 Forebay Design
Redland
TJF
Choose One
Circular (up to 2" diameter)
Rectangular (2" high)
Choose One
S.S. Well Screen with 60% Open Area*
Other (Describe):
Choose One
Aluminum Amico-Klemp SR Series (or equal)
Other (Describe):
UD-BMP for Basin 1 and 4, EDB 7/8/2013, 3:42 PM
Sheet 4 of 4
Designer:
Company:
Date:
Project:
Location:
10. Overflow Embankment
A) Describe embankment protection for 100-year and greater overtopping:
B) Slope of Overflow Embankment ZE
= ft / ft
(Horizontal distance per unit vertical, 4:1 or flatter preferred)
11. Vegetation
12. Access
A) Describe Sediment Removal Procedures
Notes:
TLE Miramont
Basin 1 and 4 Forebay Design
Design Procedure Form: Extended Detention Basin (EDB)
July 8, 2013
Redland
TJF
Choose One
Irrigated
Not Irrigated
Final Drainage Report for The Learning Experience at Miramont Office Park
16
Appendix D - Reference Documents and Excerpts
!(
!(
!(
!(
!(
E HARMONY RD
S LEMAY AVE
S TIMBERLINE RD
ZIEGLER RD
STRAUSS CABIN RD
KECHTER RD
Preston •Pond Retrofit Jr. Existing High Pond to accommodate
Water Quality Volume
Willow •Pond Retrofit Springs Existing Pond to accommodate
Water Quality Volume
Harmony •Pond Retrofit Existing Crossing Pond to accommodate
Water Quality Volume
Miramont •Pond Retrofit Existing Pond to accommodate
Water Quality Volume
McClellands Creek
Oak •Pond Retrofit Ridge Existing Pond to accommodate
Water Quality Volume
Proposed andRestoration Habitat Stream Improvements
H
F
D
C
B
Selected Plan McClellands - Water Quality Creek Basin Improvements . 1 inch = 0.125 miles
McClellands Creek Basin
Proposed BMP Basin Type
Flood Control Only
Water Quality Only
Flood Control and Water Quality
Proposed ProposedImprovements Water Quality Selected Alternatives Plan
Natural Area
Proposed Stream Restoration and Habitat Improvements
0 660 1,320 1,980 2,640
Feet
Proposed
Final Drainage Report for The Learning Experience at Miramont Office Park
17
Appendix E - Drainage Plan
M) Depth of WQCV (HWQCV) H
WQCV = feet
(Estimate using actual stage-area-volume relationship and VWQCV)
N) Ensure Minimum 40 Hour Drain Time for WQCV TD WQCV
= hours
TLE Miramont
July 8, 2013
Redland
Design Procedure Form: Extended Detention Basin (EDB)
(flow too small for berm w/ pipe)
Basin 1 and 4 Forebay Design
TJF
Choose One
Wall with Rect. Notch
Berm With Pipe
Choose One
Orifice Plate
Other (Describe):
Choose One
Concrete
Soft Bottom
Wall with V-Notch Weir
#N/A #N/A #N/A #N/A #N/A
STAGE-DISCHARGE SIZING OF THE SPILLWAY
TLE at Miramont
Existing Spillway Capacity
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A #N/A #N/A
Routing 2: Water flows through WQCV plate and #1 vertical opening and #1 horizontal opening into #2 vertical opening (#2 horizontal
opening is not used).
STAGE-DISCHARGE SIZING OF THE WEIRS AND ORIFICES (INLET CONTROL)
TLE at Miramont #12026
Current Routing Order is #2
W.S. EL. WQ
W.S. EL. Minor
W.S. EL. Major
WQ
H1
H2
V1 V2
Routing Order #1 (Standard)
V1
W.S. EL. WQ
W.S. EL. Design Storm
WQ
H1
Routing Order #3 (Single Stage) Routing Order #4
V2
V1
H1
WQ
W.S. EL. Major
W.S. EL. Minor
W.S. EL. WQ
W.S. EL. Emergency Spillway
Emergency Overflow into Pipe- H2
V2
H1
WQ
W.S. EL. Major
W.S. EL. Minor
W.S. EL. WQ V1
Routing Order #2
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
#N/A #N/A #N/A #N/A #N/A #N/A
Central Elevations of Rows of Holes in feet
Collection Capacity for Each Row of Holes in cfs
STAGE-DISCHARGE SIZING OF THE WATER QUALITY CAPTURE VOLUME (WQCV) OUTLET
TLE at Miramont #12026
#N/A #N/A
#N/A #N/A
STAGE-STORAGE SIZING FOR DETENTION BASINS
TLE AT Miramont
Check Basin Shape
175 0.65 0.388 0.54 0.39 0.095 0.294 175 1.33 0.921 0.54 0.98 0.236 0.685
180 0.64 0.391 0.54 0.39 0.097 0.294 180 1.30 0.928 0.54 0.98 0.243 0.685
185 0.62 0.394 0.54 0.39 0.100 0.294 185 1.27 0.934 0.54 0.98 0.249 0.686
190 0.61 0.396 0.53 0.39 0.102 0.294 190 1.25 0.941 0.53 0.97 0.255 0.686
195 0.60 0.399 0.53 0.39 0.105 0.294 195 1.22 0.947 0.53 0.97 0.261 0.685
200 0.59 0.401 0.53 0.39 0.107 0.294 200 1.20 0.953 0.53 0.97 0.268 0.685
205 0.58 0.404 0.53 0.39 0.110 0.294 205 1.18 0.959 0.53 0.97 0.274 0.685
210 0.57 0.406 0.53 0.39 0.112 0.294 210 1.16 0.964 0.53 0.97 0.280 0.684
215 0.56 0.409 0.53 0.39 0.115 0.294 215 1.14 0.970 0.53 0.97 0.287 0.683
220 0.55 0.411 0.53 0.39 0.117 0.294 220 1.12 0.975 0.53 0.97 0.293 0.683
225 0.54 0.413 0.53 0.39 0.120 0.294 225 1.10 0.981 0.53 0.97 0.299 0.682
230 0.53 0.416 0.53 0.39 0.122 0.293 230 1.08 0.986 0.53 0.96 0.305 0.681
235 0.52 0.418 0.53 0.39 0.125 0.293 235 1.06 0.991 0.53 0.96 0.312 0.680
240 0.51 0.420 0.53 0.38 0.127 0.293 240 1.05 0.996 0.53 0.96 0.318 0.678
245 0.50 0.422 0.53 0.38 0.130 0.292 245 1.03 1.001 0.53 0.96 0.324 0.677
250 0.50 0.424 0.53 0.38 0.132 0.292 250 1.01 1.006 0.53 0.96 0.331 0.676
255 0.49 0.426 0.53 0.38 0.135 0.291 255 1.00 1.011 0.53 0.96 0.337 0.674
260 0.48 0.428 0.53 0.38 0.137 0.291 260 0.98 1.016 0.53 0.96 0.343 0.673
265 0.47 0.430 0.52 0.38 0.140 0.290 265 0.97 1.020 0.52 0.96 0.349 0.671
270 0.47 0.432 0.52 0.38 0.142 0.290 270 0.96 1.025 0.52 0.96 0.356 0.669
275 0.46 0.434 0.52 0.38 0.145 0.289 275 0.94 1.030 0.52 0.96 0.362 0.668
280 0.46 0.436 0.52 0.38 0.147 0.288 280 0.93 1.034 0.52 0.95 0.368 0.666
285 0.45 0.438 0.52 0.38 0.150 0.288 285 0.92 1.038 0.52 0.95 0.375 0.664
290 0.44 0.439 0.52 0.38 0.152 0.287 290 0.91 1.043 0.52 0.95 0.381 0.662
295 0.44 0.441 0.52 0.38 0.155 0.286 295 0.89 1.047 0.52 0.95 0.387 0.660
300 0.43 0.443 0.52 0.38 0.157 0.286 300 0.88 1.051 0.52 0.95 0.393 0.658
Mod. FAA Minor Storage Volume (cubic ft.) = 14,381 Mod. FAA Major Storage Volume (cubic ft.) = 27,036
Mod. FAA Minor Storage Volume (acre-ft.) = 0.3301 Mod. FAA Major Storage Volume (acre-ft.) = 0.6207
Determination of MINOR Detention Volume Using Modified FAA Method Determination of MAJOR Detention Volume Using Modified FAA Method
DETENTION VOLUME BY THE MODIFIED FAA METHOD
TLE at Miramont
Basin A
(For catchments less than 160 acres only. For larger catchments, use hydrograph routing method)
(NOTE: for catchments larger than 90 acres, CUHP hydrograph and routing are recommended)
10/1/2013
DIRECT RUNOFF TOTAL RUNOFF STREET PIPE TRAVEL TIME
0.81 13.38
8.24 0.59
A7 A7 0.18 0.70 8.22 8.33
9.42
Sum of A2 and A7 (Inlet 1-1)
A6 A6
A5 A5 0.11 0.83 5.58 0.09 9.42
A2
0.87 6.58 0.56 8.96
0.12
0.11 0.83 5.58
B2 B2 0.76 0.82 10.42
B1 B1 0.38 0.83 5.00 0.31
0.09
STORM
LINE
(1)
Inlet 1-2 A1 A1 2.26
8.47
Sum of A1 and A4
A2 A2 0.65
A3 A3 0.21 0.52 5.00
B3 B3
0.06 0.79
A4 A4 0.13 0.31 8.45 0.04 4.04 0.17
0.71 13.38 1.61 3.35 5.39
STORM
LINE
(1)
Inlet 1-2 A1 A1 2.26
STANDARD FORM SF-3 - DEVELOPED
STORM DRAINAGE DESIGN - RATIONAL METHOD 2 YEAR EVENT
10/1/2013
DIRECT RUNOFF TOTAL RUNOFF STREET PIPE TRAVEL TIME
8.45 0.02 2.36 0.04
2.26
1.34
0.08 2.70
8.2 0.56 2.39
0.18 0.46 8.22 0.08 2.39
2.85
0.22
0.64 13.38
Sum of A2 and A7 (Inlet 1-1)
A6 A6 0.11 0.73 5.58 0.22
Sum on A1 and A4
A2 A2 0.65 0.74 6.58 0.48 2.57 1.23
A5 A5 0.11 0.73 5.58 0.08
1.44
13.4 1.45 1.96
1.96 2.82
0.04
B2 B2 0.76
A3 A3 0.21
0.57 8.47 0.04 2.36
0.25 2.78 0.69
0.64 10.42 0.49
B3 B3
0.06
2.18 1.06
0.09
A2