HomeMy WebLinkAboutDrainage Reports - 03/19/2020February 12, 2020
Mr. Matt Simpson
City of Fort Collins
700 Wood Street
Fort Collins, Colorado 80521
RE: Drainage Memo for Odell Wine Project
824 E. Lincoln Ave., Fort Collins, Colorado
Dear Mr. Simpson,
The Odell Wine Project, at 824 E. Lincoln Avenue, is a proposed expansion to the brewery
operations for the Odell Brewery on 800 E. Lincoln Avenue. The site is currently composed of a
steel frame industrial building and hardscape (asphalt and concrete) parking lot with concrete
. Odell
proposes to repurpose the existing building as a wine and beer tasting room. Improvements
consists of renovations to the existing building, an outdoor patio, permeable pavers, new
sidewalks, and new landscaping.
The original drainage report, Storm Drainage Report for Building Addition at the 824 East Lincoln
Avenue (Lot 1 Patrick Subdivision), for this project was prepared in September 1995 by Stewart
and Associates. Subsequently, a regional detention pond, the East Pond, was constructed on
800 E. Lincoln Avenue to provide detention for both 800 and 824 E. Lincoln Avenue. The East
Pond was further revised on April 22, 2013 (Odell Brew House Drainage Letter Report Amendment
by Northern Engineering) for the 100-year storm event from both 800 and 824 E. Lincoln
Avenue. However, the East Pond was constructed with less than the design volume (Addendum
to Final Drainage Certification Memorandum for 2013 Odell Brew House Expansion by Northern
Engineering dated February 18, 2014). According to Table 1, the East Pond is short by 1,791
cubic feet. The shortage in volume is caused by the burden on the East Pond from 824 E.
Lincoln Avenue. Additional concrete improvements in 2015 resulted in further aggravating the
burden on the East Pond.
City of Fort Collins Approved Plans
Approved by:
Date:
Matt Simpson
03/19/2020
Page 2
Asbuilt Detention Volumes for 800 E. Lincoln Ave.
Required
Volume1
800 E. Lincoln Ave. 11,118 ft3
824 E. Lincoln Ave. 2,554 ft3
Total 13,672 ft3
Asbuilt Volume1
Permeable Pavers 2,261 ft3
East Pond 9,620 ft3
Total 11,881 ft3
All volumes from Addendum to Final Drainage Certification Memorandum
for 2013 Odell Brew House Expansion by Northern Engineering dated
02/18/2014.
Table 1: Detention Volumes for 800 E. Lincoln Avenue
The project proposes to reduce the overall impervious area of the site by 1,098 square feet. The
existing impervious area is 27,036 square feet. The proposed impervious area is 25,939 square
feet. However, the historic runoff limitations dictated by the original drainage report, Storm
Drainage Report for Building Addition at the 824 East Lincoln Avenue (Lot 1 Patrick Subdivision), and
the burden on the East Pond require detention for the project.
The project will utilize permeable pavers to address the burden to the East Pond, meet LID
requirements, and any additional detention required by the proposed improvements to 824 E.
Lincoln Avenue (Odell Wine Project). According to the original drainage report, Storm Drainage
Report for Building Addition at the 824 East Lincoln Avenue (Lot 1 Patrick Subdivision), 0.67 acres of
the project site was limited to a runoff of 0.5 cfs and the remaining 0.32 acres was allowed to
flow undetained into Lincoln Avenue. An analysis of the Historic Basins (see attached Historic
Hydrological Calculations), while maintaining the historic flowrates per the original drainage
report, results in an allowable 100-Year release rate of 3.70 cfs for the entire site. The permeable
pavers for 824 E. Lincolne Avenue (Odell Wine Project) will have a release rate of 1.19 cfs. A
detention volume of 2,251 cubic feet will be required to maintain a runoff of less than 3.70 cfs
for the entire site.
The project was divided into four (4) onsite and five (5) offsite proposed drainage basins further
described below. Basin A-1, located within the front half of the site, consists of that portion of
the project that drains into the proposed permeable pavers. Basin A-2, located in the back half
of the site, consists of that portion of the project that will continue to drain into the East Pond on
800 E. Lincoln Avenue. Basin B consists of a tiny sliver of landscaping along the front that
drains into the existing storm sewer in Lincoln Avenue. Basin C consists of the northeast corner
of the project that drains onto the neighboring property to the east. Except for some curb and
Page 3
gutter to help facilitate drainage within Basin A-1, the project site does not alter the historic
drainage patterns.
Runoff from Basins A-2, B, and C will flow undetained, but there is 763 cubic feet within the East
Pond available to Basin A-2. Runoff from Basin A-1 will flow into the proposed permeable
pavers. The permeable pavers . The
project site will conform with the requirement to treat a minimum of 50% of new impervious area
using permeable pavers.
The hillside along the north property line, located within offsite basins OS-1 and OS-2, is a
significant source of offsite drainage impacting the site. Basins OS-1 and OS-2 are divided on
whether the flow towards the east or west property lines. The project proposes a swale along
the north property line to redirect drainage in OS-1 and OS-2, from impacting the permeable
pavers in Basin A-. Additional
offsite basins (OS-3, OS-4, and OS-5) include those portions of the project located within the
Lincoln Avenue right-of-way or 800 E. Lincoln Avenue.
The Odell Wine Project will reduce the burden on the East Pond for 800 E. Lincoln Street. Upon
completion of the permeable pavers for Odell Wine Project, the East Pond for 800 E. Lincoln Street
will be in compliance with City of Fort Collins stormwater regulations. In addition, the Odell
Wine Project will maintain the historic runoffs per Storm Drainage Report for Building Addition at
the 824 East Lincoln Avenue (Lot 1 Patrick Subdivision). 568.5408
or fred@northernengineering.com.
LID Treatment from Permeable Pavers:
Impervious Area Requiring LID (2015): 1,573 ft2
Impervious Area Requiring LID (2020): 7,215 ft2
Impervious Area Requiring LID (Total): 8,788 ft2
Impervious Area Receiving of LID: 9,040 ft2
Pavers Surface Area: 2,986 ft2
Runon Ratio: 3.0
Page 4
Sincerely,
Northern Engineering Services, Inc.
I hereby attest this report for the final drainage design for the Odell Wine Project was prepared
by me or under my direct supervision, in accordance with the provisions of the Fort Collins
Stormwater Criteria Manual. I understand that the City of Fort Collins does not and will not
assume liability for drainage facilities designed by others.
Registered professional engineer must affix their seal with signature and date.
Frederick S. Wegert, PE
Project Engineer
Attachments:
Hydrology Calculations
LID & Permeable Paver Calculations
Inlet Calculations
East Pond Drainage Certifications
Drainage Exhibit
cc: Michael McBride, MMLA; Rebecca Spears, RB+B Architects
2/12/202
Tc2 Tc10 Tc100 C2 C10 C100
I2
(in/hr)
I10
(in/hr)
I100
(in/hr)
Q2
(cfs)
Q10
(cfs)
Q100
(cfs)
ha HA 0.573
11.16 11.16 7.77 0.67 0.67 0.84 2.13 3.63 8.59 0.82 1.40 4.14
a1 HB 0.420
5.18 5.18 5.00 0.61 0.61 0.77 2.85 4.87 9.95 0.73 1.25 3.20
hos1 HOS1 0.174
8.48 8.48 8.14 0.20 0.20 0.25 2.40 4.10 8.38 0.08 0.14 0.36
a3 HOS2 0.035 6.23 6.23 5.89 0.20 0.20 0.25 2.67 4.56 9.63 0.02 0.03 0.08
hos3 HOS3 0.028 7.05 7.05 6.24 0.35 0.35 0.44 2.52 4.31 9.31 0.02 0.04 0.11
a5 HOS4 0.030 5.00 5.00 5.00 0.42 0.42 0.52 2.85 4.87 9.95 0.04 0.06 0.15
HISTORIC DIRECT RUNOFF COMPUTATIONS
Intensity Flow
Odell Wine
F. Wegert
February 12, 2020
Project:
Calculations By:
Overland Flow, Time of Concentration:
Gutter/Swale Flow, Time of Concentration:
Date:
Rational Equation: Q = CiA (Equation 6-1)
Design
Point Basin Area
(acres)
Runoff C
Tt = L / 60V (Equation 6-4 per MHFD)
Tc = Ti + Tt (Equation 6-2 per MHFD)
Velocity (Gutter Flow), V = 20·S ½
Velocity (Swale Flow), V = 15·S ½
Intensity, I from Fig. 3.4.1 Fort Collins Stormwater Manual
Tc (Min)
(Equation 6-4 per MHFD)}
(Equation 3.3-2 per Fort Collins
Stormwater Manual)
Page 1 of 1
Tc2 Tc10 Tc100 C2 C10 C100
I2
(in/hr)
I10
(in/hr)
I100
(in/hr)
Q2
(cfs)
Q10
(cfs)
Q100
(cfs)
a-1 A-1 0.536
9.91 9.91 5.86 0.75 0.75 0.94 2.26 3.86 9.63 0.91 1.56 4.86
a-2 A-2 0.255
11.64 11.64 10.79 0.57 0.57 0.71 2.09 3.57 7.57 0.30 0.52 1.37
b B 0.012
5.69 5.69 5.39 0.20 0.20 0.25 2.76 4.72 9.95 0.01 0.01 0.03
c C 0.190 10.13 10.13 9.07 0.43 0.43 0.54 2.21 3.78 8.03 0.18 0.31 0.82
os-1 OS-1 0.174 8.02 8.02 7.57 0.27 0.27 0.34 2.40 4.10 8.59 0.11 0.19 0.50
os-2 OS-2 0.035 6.23 6.23 5.89 0.20 0.20 0.25 2.67 4.56 9.63 0.02 0.03 0.08
os-3 OS-3 0.017 5.00 5.00 5.00 0.20 0.20 0.25 2.85 4.87 9.95 0.01 0.02 0.04
os-4 OS-4 0.011 5.00 5.00 5.00 0.67 0.67 0.83 2.85 4.87 9.95 0.02 0.04 0.09
os-5 OS-5 0.030 5.00 5.00 5.00 0.43 0.43 0.54 2.85 4.87 9.95 0.04 0.06 0.16
a-1 A-B 0.803 10.35 10.35 7.04 0.69 0.69 0.86 2.21 3.78 8.80 1.22 2.08 6.07
a-1 Pavers 1.005 11.39 11.39 8.93 0.61 0.61 0.77 2.13 3.63 8.21 1.31 2.24 6.32
a-1 A-OS1 1.434 10.87 10.87 9.92 0.56 0.56 0.70 2.17 3.71 7.88 1.75 2.99 7.95
c C-OS2 0.225 6.85 6.85 6.19 0.39 0.39 0.49 2.60 4.44 9.31 0.23 0.39 1.03
Runoff C
Tt = L / 60V (Equation 6-4 per MHFD)
Tc = Ti + Tt (Equation 6-2 per MHFD)
Velocity (Gutter Flow), V = 20·S ½
Velocity (Swale Flow), V = 15·S ½
Intensity, I from Fig. 3.4.1 Fort Collins Stormwater Manual
Tc (Min)
Combined Basins
DEVELOPED DIRECT RUNOFF COMPUTATIONS
Intensity Flow
Odell Wine
F. Wegert
February 12, 2020
Project:
Calculations By:
Overland Flow, Time of Concentration:
Gutter/Swale Flow, Time of Concentration:
Date:
Rational Equation: Q = CiA (Equation 6-1)
Design
Point Basin Area
(acres)
(Equation 6-4 per MHFD)}
(Equation 3.3-2 per Fort Collins
Stormwater Manual)
Page 1 of 1
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Pond No :
A1
100-yr
1.00
9.90 min 2251 ft3
0.54 acres 0.05 ac-ft
Max Release Rate =1.19 cfs
Time (min)
Ft Collins
100-yr
Intensity
(in/hr)
Inflow
Volume
(ft3)
Qav
(cfs)
Outflow Volume
(ft3)
Storage
Volume
(ft3)
5 9.950 1612 1.19 357 1255
10 7.720 2501 1.19 714 1787
15 6.520 3169 1.19 1071 2098
20 5.600 3629 1.19 1428 2201
25 4.980 4034 1.19 1785 2249
30 4.520 4393 1.19 2142 2251
35 4.080 4627 1.19 2499 2128
40 3.740 4847 1.19 2856 1991
45 3.460 5045 1.19 3213 1832
50 3.230 5233 1.19 3570 1663
55 3.030 5399 1.19 3927 1472
60 2.860 5560 1.19 4284 1276
65 2.720 5728 1.19 4641 1087
70 2.590 5874 1.19 4998 876
75 2.480 6026 1.19 5355 671
80 2.380 6169 1.19 5712 457
85 2.290 6307 1.19 6069 238
90 2.210 6444 1.19 6426 18
95 2.130 6556 1.19 6783 -227
100 2.060 6674 1.19 7140 -466
105 2.000 6804 1.19 7497 -693
110 1.940 6914 1.19 7854 -940
115 1.890 7042 1.19 8211 -1169
120 1.840 7154 1.19 8568 -1414
*Note: Using the method described in Urban Storm Drainage Criteria Manual Volume 2.
DETENTION POND CALCULATION: MODIFIED FAA METHOD w/ Ft Collins IDF
Input Variables Results
Required Detention Volume
Fort Collins, Colorado
100-020
Odell Wine Project
Project Number :
Project Name :
Permeable Pavers
A =
Tc =
Project Location :
Design Point
C =
Design Storm
Page 1 of 1
100-020_Pond_FAA.xls
Project Number :
Project Name :
Project Location :
Pond No :
800 E. Lincoln Ave. 11,118
ft3
824 E. Lincoln Ave. 2,554
ft3
Total 13,672
ft3
Permeable Pavers 2,261
ft3
East Pond 9,620
ft3
Total 11,881
ft3
2,251 ft3
2,261 ft3
800 E. Lincoln Ave. 8,857 ft3
824 E. Lincoln Ave. (100% of Basin A-2) 763
ft3
Asbuilt Volume 9,620
ft3
30%
3,870 ft2
23.3 in
6.0 in
4.0 in
26.0 in
36.0 in
2,515 ft3
2,251 ft3
Paver & Levelling Course Depth (per FC standard details)3
Design Depth of Subbase
Base Depth (per FC standard details)3
Required Volume (100% of Basin A-1)
Permeable Pavers (800 E. Lincoln Ave.)
Permeable Paver Section (824 E. Lincoln Avenue - Detains 100% of Basin A-1)
Assumed Void Ratio per FCSM2
Asbuilt Volume1
Allocation of Detention Resources on 800 E. Lincoln Ave.
Required Volumes of 824 E. Lincoln Avenue
Required Detention Vol. for 824 E. Lincoln Ave. for Basin A-1
Area of Pavers
East Pond
Asbuilt Detention Volumes for 800 E. Lincoln Ave.
Required Volume1
PERMEABLE PAVER VOLUME & SECTION
Design Volume
100-020
Odell Wine Project
Fort Collins, Colorado
Permeable Pavers
Calculated Depth of Required Subbase (minimum)
Total Depth of Permeable Paver Section
Notes:
1) All volumes from Addendum to Final Drainage Certification Memorandum for 2013 Odell Brew House Expansion by Northern
Engineering dated 02/18/2014.
2) FCSM = Fort Collins Stormwater Manual.
3) Paver depths based on standard Fort Collins detail D-54.
Project Number:
Project:
Date:
Prepared By:
Pond Data
Rim Elev./Finish Ground 4944.94
100-yr WSEL 4944.11
Pipe Invert Elev.4942.48
Orifice Plate
Outflow Q 1.19 cfs
Orifice Coefficient Cd 0.62
Gravity Constant g 32.2 ft/s^2
100-year head H 1.63 ft
Orifice Area Ao 0.19 ft^2
Orifice Area Ao 27.00 in^2
Calculated Radius r 2.9 in
Calculated Diameter d 5.9 in
Orifice Curve
Stage (ft)H (ft) Q (cfs) Storage Stage Note
4942.48 0.00 0.00 0.00 Orifice Invert
4942.73 0.25 0.47 0.25
4942.98 0.50 0.66 0.50
4943.23 0.75 0.81 0.75
4943.48 1.00 0.93 1.00
4943.73 1.25 1.04 1.25
4943.98 1.50 1.14 1.50
4944.15 1.67 1.21 1.67 100-yr WSEL
4944.48 2.00 1.32 2.00
4944.73 2.25 1.40 2.25
4944.94 2.46 1.46 2.46
Top of Pavers/Finish Ground
ORIFICE RATING CURVE
Permeable Paver Outlet 100-yr Orifice
100-020
Odell Wine
2/12/2020
F. Wegert
2/10/2020 2:16 PM P:\100-020\Drainage\Detention\100-020_Orifice.xlsx\Orifice Size
Area Inlet Performance Curve:
Permeable Pavers (South)
Governing Equations:
At low flow depths, the inlet will act like a weir governed by the following equation:
* where P = 3.1416*Dia.of grate
* where H corresponds to the depth of water above the flowline
At higher flow depths, the inlet will act like an orifice governed by the following equation:
* where A equals the open area of the inlet grate
* where H corresponds to the depth of water above the centroid of the cross-sectional area (A)
The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown.
However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation
will cross at a certain flow depth. The two curves can be found below:
If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir.
Input Parameters:
Type of Grate: Nyloplast 8" Grate
Diameter of Grate (ft): 0.666666667
Open Area of Grate (ft2):0.21
Rim Elevation (ft): 4944.930
Reduction Factor: 50%
Depth vs. Flow:
Depth Above Inlet (ft)
Elevation
(ft)
Shallow
Weir Flow
(cfs)
Orifice
Flow
(cfs)
Actual
Flow
(cfs)
0.00 4944.93 0.00 0.00 0.00
0.20 4945.13 0.28 0.25 0.25
0.40 4945.33 0.79 0.36 0.36
0.60 4945.53 1.46 0.44 0.44
0.80 4945.73 2.25 0.50 0.50 <-2-Year
1.00 4945.93 3.14 0.56 0.56
1.20 4946.13 4.13 0.62 0.62
1.40 4946.33 5.20 0.67 0.67
1.60 4946.53 6.36 0.71 0.71
1.80 4946.73 7.59 0.76 0.76
2.35 4947.28 11.32 0.86 0.86 <-10-Year
10-Year Design Flow = 0.86 cfs 2-Year Design Flow = 0.50 cfs
5.10.3 HPQ
5.0)2(67.0 gHAQ
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
Di
s
c
h
a
r
g
e
(
c
f
s
)
Stage (ft)
Stage - Discharge Curves
Weir Flow
Orifice Flow
Assumes permeable pavers are 100% clogged.
Area Inlet Performance Curve:
Permeable Pavers (North)
Governing Equations:
At low flow depths, the inlet will act like a weir governed by the following equation:
* where P = 3.1416*Dia.of grate
* where H corresponds to the depth of water above the flowline
At higher flow depths, the inlet will act like an orifice governed by the following equation:
* where A equals the open area of the inlet grate
* where H corresponds to the depth of water above the centroid of the cross-sectional area (A)
The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown.
However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation
will cross at a certain flow depth. The two curves can be found below:
If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir.
Input Parameters:
Type of Grate: Nyloplast 8" Grate
Diameter of Grate (ft): 0.666666667
Open Area of Grate (ft2):0.21
Rim Elevation (ft): 4945.940
Reduction Factor: 50%
Depth vs. Flow:
Depth Above Inlet (ft)
Elevation
(ft)
Shallow
Weir Flow
(cfs)
Orifice
Flow
(cfs)
Actual
Flow
(cfs)
0.00 4945.94 0.00 0.00 0.00
0.20 4946.14 0.28 0.25 0.25
0.40 4946.34 0.79 0.36 0.36
0.60 4946.54 1.46 0.44 0.44
0.80 4946.74 2.25 0.50 0.50 <-2-Year
1.00 4946.94 3.14 0.56 0.56
1.20 4947.14 4.13 0.62 0.62
1.40 4947.34 5.20 0.67 0.67
1.60 4947.54 6.36 0.71 0.71
1.80 4947.74 7.59 0.76 0.76
2.35 4948.29 11.32 0.86 0.86 <-10-Year
10-Year Design Flow = 0.86 cfs 2-Year Design Flow = 0.50 cfs
5.10.3 HPQ
5.0)2(67.0 gHAQ
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00
Di
s
c
h
a
r
g
e
(
c
f
s
)
Stage (ft)
Stage - Discharge Curves
Weir Flow
Orifice Flow
Assumes permeable pavers are 100% clogged.
Area Inlet Performance Curve:
North Inlet (OS-1 & OS-2)
Governing Equations:
At low flow depths, the inlet will act like a weir governed by the following equation:
* where P = 3.1416*Dia.of grate
* where H corresponds to the depth of water above the flowline
At higher flow depths, the inlet will act like an orifice governed by the following equation:
* where A equals the open area of the inlet grate
* where H corresponds to the depth of water above the centroid of the cross-sectional area (A)
The exact depth at which the inlet ceases to act like a weir, and begins to act like an orifice is unknown.
However, what is known, is that the stage-discharge curves of the weir equation and the orifice equation
will cross at a certain flow depth. The two curves can be found below:
If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir.
Input Parameters:
Type of Grate: Nyloplast 15" Dome
Diameter of Grate (ft): 1.25
Open Area of Grate (ft2):0.74
Rim Elevation (ft): 4945.750
Reduction Factor: 50%
Depth vs. Flow:
Depth Above Inlet (ft)
Elevation
(ft)
Shallow
Weir Flow
(cfs)
Orifice
Flow
(cfs)
Actual
Flow
(cfs)
0.00 4945.75 0.00 0.00 0.00
0.12 4945.87 0.24 0.69 0.24 <-10-Year
0.20 4945.95 0.53 0.88 0.53
0.22 4945.97 0.59 0.92 0.59 <-100-Year
0.40 4946.15 1.49 1.25 1.25
0.60 4946.35 2.74 1.53 1.53
0.80 4946.55 4.21 1.77 1.77
1.00 4946.75 5.89 1.98 1.98
1.20 4946.95 7.74 2.17 2.17
1.40 4947.15 9.76 2.34 2.34
1.60 4947.35 11.92 2.50 2.50
10-Year Design Flow = 0.22 cfs100-Year Design Flow = 0.58 cfs
5.10.3 HPQ
5.0)2(67.0 gHAQ
0.00
2.00
4.00
6.00
8.00
10.00
12.00
0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Di
s
c
h
a
r
g
e
(
c
f
s
)
Stage (ft)
Stage - Discharge Curves
Weir Flow
Orifice Flow
02.03.14
02.18.14