HomeMy WebLinkAboutTHE ODELL WINE PROJECT - FDP200001 - SUBMITTAL DOCUMENTS - ROUND 2 - DRAINAGE REPORTFebruary 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
and gravel industrial access. The building is currently used for Odell’s barrel storage. 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.
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 will meet the project’s detention and LID requirements. 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-1, into an existing 15” storm sewer along the west property line. 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). Don’t hesitate to contact me at 970.568.5408
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
0
Runoff
Coefficient1
Percent
Impervious1
0.95 100%
0.95 90%
0.80 80%
0.50 40%
0.10 2%
0.20 2%
Basin ID
Basin Area
(sq.ft.)
Basin Area
(acres)
Asphalt,
Concrete (acres)
Rooftop (acres)
Recycled Asphalt
(acres)
Gravel (acres)
Lawns, Sandy
Soil, Flat Slope <
2% (acres)
Lawns, Clayey
Soil, Flat Slope <
2% (acres)
Percent
Impervious
C2*Cf
Cf
= 1.00
C5*Cf
Cf = 1.00
C10*Cf
Cf = 1.00
C100*Cf
Cf = 1.25
HA 24,980 0.573 0.145 0.139 0.000 0.194 0.000 0.10 61% 0.67 0.67 0.67 0.84
HB 18,275 0.420 0.116 0.083 0.000 0.083 0.000 0.14 54% 0.61 0.61 0.61 0.77
HOS1 7,579 0.174 0.000 0.000 0.000 0.000 0.000 0.17 2% 0.20 0.20 0.20 0.25
HOS2 1,519 0.035 0.000 0.000 0.000 0.000 0.000 0.03 2% 0.20 0.20 0.20 0.25
HOS3 1,202 0.028 0.006 0.000 0.000 0.000 0.000 0.02 22% 0.35 0.35 0.35 0.44
HOS4 1,300 0.030 0.000 0.000 0.000 0.021 0.000 0.01 29% 0.42 0.42 0.42 0.52
Lawns and Landscaping:
2) Composite Runoff Coefficient adjusted per Table 3.2-3 of the Fort Collins
Stormwater Manual (FCSM).
Lawns, Clayey Soil, Flat Slope < 2%
USDA SOIL TYPE: C
Lawns, Sandy Soil, Flat Slope < 2% Composite Runoff Coefficient2
1) Runoff coefficients per Tables 3.2-1 & 3.2 of the FCSM. Percent impervious per Tables 4.1-2 & 4.1-3 of the FCSM.
HISTORIC RUNOFF COEFFICIENT CALCULATIONS
Asphalt, Concrete
Rooftop
Recycled Asphalt
Gravel
Odell Wine
F. Wegert
February 12, 2020
Project:
Project:
Calculations By:
Date:
Length
(ft)
Elev
Up
Elev
Down
Slope
(%)
Ti
2-Yr
(min)
Ti
10-Yr
(min)
Ti
100-Yr
(min)
Length
(ft)
Elev
Up
Elev
Down
Slope
(%)
Velocity
(ft/s)
Tt
(min)
Length
(ft)
Elev
Up
Elev
Down
Slope
(%)
Velocity
(ft/s)
Tt
(min)
Max.
Tc 2-Yr
(min)
Tc
2-Yr
(min)
Max.
Tc 10-Yr
(min)
Tc
10-Yr
(min)
Max.
Tc 100-Yr
(min)
Tc
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·S½
Velocity (Swale Flow), V = 15·S½
Intensity, I from Fig. 3.4.1 Fort Collins Stormwater Manual
Tc (Min)
} (Equation 6-4 per MHFD)
𝑇𝑖 =
1.87 1.1 − 𝐶 ∗ 𝐶𝑓 𝐿
𝑆 ൗ
1
3
(Equation 3.3-2 per Fort Collins
Stormwater Manual)
Page 1 of 1
Runoff
Coefficient1
Percent
Impervious1
0.95 100%
0.95 90%
0.50 40%
0.50 40%
0.10 2%
0.20 2%
Basin ID
Basin Area
(sq.ft.)
Basin Area
(acres)
Asphalt,
Concrete (acres)
Rooftop (acres) Gravel (acres) Pavers (acres)
Lawns, Sandy
Soil, Flat Slope <
2% (acres)
Lawns, Clayey
Soil, Flat Slope <
2% (acres)
Percent
Impervious
C2*Cf
Cf
= 1.00
C5*Cf
Cf = 1.00
C10*Cf
Cf = 1.00
C100*Cf
Cf = 1.25
A-1 23,328 0.536 0.230 0.126 0.032 0.066 0.000 0.08 72% 0.75 0.75 0.75 0.94
A-2 11,103 0.255 0.068 0.045 0.032 0.000 0.000 0.11 48% 0.57 0.57 0.57 0.71
B 532 0.012 0.000 0.000 0.000 0.000 0.000 0.01 2% 0.20 0.20 0.20 0.25
C 8,292 0.190 0.004 0.049 0.013 0.000 0.000 0.12 29% 0.43 0.43 0.43 0.54
OS-1 7,579 0.174 0.016 0.000 0.000 0.000 0.000 0.16 11% 0.27 0.27 0.27 0.34
OS-2 1,519 0.035 0.000 0.000 0.000 0.000 0.000 0.03 2% 0.20 0.20 0.20 0.25
OS-3 729 0.017 0.000 0.000 0.000 0.000 0.000 0.02 2% 0.20 0.20 0.20 0.25
OS-4 474 0.011 0.007 0.000 0.000 0.000 0.000 0.00 63% 0.67 0.67 0.67 0.83
OS-5 1,291 0.030 0.005 0.000 0.000 0.010 0.000 0.01 32% 0.43 0.43 0.43 0.54
A-B 34,963 0.803 0.298 0.171 0.065 0.066 0.000 0.20 63% 0.69 0.69 0.69 0.86
Pavers 43,774 1.005 0.326 0.171 0.065 0.076 0.000 0.37 54% 0.61 0.61 0.61 0.77
A-OS1 62,456 1.434 0.410 0.215 0.097 0.076 0.000 0.64 48% 0.56 0.56 0.56 0.70
C-OS2 9,811 0.225 0.004 0.049 0.013 0.000 0.000 0.16 25% 0.39 0.39 0.39 0.49
DEVELOPED RUNOFF COEFFICIENT CALCULATIONS
Asphalt, Concrete
Rooftop
Gravel
Pavers
Odell Wine
F. Wegert
February 12, 2020
Project:
Calculations By:
Date:
Character of Surface
Project:
Calculations By:
Date:
Length
(ft)
Elev
Up
Elev
Down
Slope
(%)
Ti
2-Yr
(min)
Ti
10-Yr
(min)
Ti
100-Yr
(min)
Length
(ft)
Elev
Up
Elev
Down
Slope
(%)
Velocity
(ft/s)
Tt
(min)
Length
(ft)
Elev
Up
Elev
Down
Slope
(%)
Velocity
(ft/s)
Tt
(min)
Max.
Tc 2-Yr
(min)
Tc
2-Yr
(min)
Max.
Tc 10-Yr
(min)
Tc
10-Yr
(min)
Max.
Tc 100-Yr
(min)
Tc
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·S½
Velocity (Swale Flow), V = 15·S½
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)
𝑇𝑖 =
1.87 1.1 − 𝐶 ∗ 𝐶𝑓 𝐿
𝑆 ൗ
1
3
(Equation 3.3-2 per Fort Collins
Stormwater Manual)
Page 1 of 1
X
X
X
X
X
RD RD
X
X
ROOFTOP
CONCRETE
ASPHALT
GRAVEL
SURFACE
AREA (SF) % IMPERV.
IMPERV.
AREA (SF)
9,645
8,645
2,711
12,070
100%
100%
100%
50% 6,035
TOTALS 43,255 TOTAL= 27,036
ROOFTOP
CONCRETE
PAVERS
GRAVEL
SURFACE
AREA (SF) % IMPERV.
IMPERV.
AREA (SF)
11,726
2,986
3,383
100%
100%
50%
50%
TOTALS 43,255 TOTAL= 25,939
EXISTING PROPOSED
1,692
1,448
P:\100-020\DWG\DRNG\100-020_IMPV.DWG
824 E. LINCOLN AVENUE
FORT COLLINS
COLORADO
Fort Collins: 301 N. Howes St., Ste. 100, 80521
Greeley: 820 8th Street, 80631
ENGINEER ING
N O R T H E RN
PHONE: 970.221.4158
www.northernengineering.com
DESCRIPTION
EXISTING VS. PROPOSED
IMPERVIOUS AREA
DRAWN BY
F. WEGERT
DATE
Project:
Calc. By:
Date:
sq. ft. acres
HA 24,980 0.57 0.82 1.40 4.14
Basin HA limited to 0.5 cfs per Storm Drainage Report for Building Addition at the 824
East Lincoln Avenue (Lot 1 Patrick Subdivision) prepared by Stewart and Associates
dated September 14, 1995.
HB 18,275 0.42 0.73 1.25 3.20
Basin HB was released undetained per Storm Drainage Report for Building Addition at
the 824 East Lincoln Avenue (Lot 1 Patrick Subdivision) prepared by Stewart and
Associates dated September 14, 1995.
Total 43,255 0.99 1.23 1.75 3.70 Release rate from HA is limited to 0.5 cfs.
sq. ft. acres
A-1 23,328 0.54 0.91 1.56 4.86 Detention required
A-2 11,103 0.25 0.30 0.52 1.37
Will be release undetained. However, basin flows into East Pond on 800 East Lincoln
Avenue.
B 532 0.01 0.01 0.01 0.03 Will be release undetained
C 8,292 0.19 0.18 0.31 0.82 Will be release undetained
Total 43,255 0.99 1.40 2.40 7.08
sq. ft. acres
A-1 23,328 0.54 1.01 1.19 1.19 Orifice plate in permeable pavers outlet will limit flow to 1.19 cfs.
A-2 11,103 0.25 0.30 0.52 1.37
Will be release undetained. However, basin flows into East Pond on 800 East Lincoln
Avenue.
B 532 0.01 0.01 0.01 0.03 Will be release undetained
C 8,292 0.19 0.18 0.31 0.82 Will be release undetained
Total 43,255 0.99 1.50 2.03 3.41 Less than historic site release rate of 3.70 cfs.
100-Year
(cfs)
Notes
HISTORIC VS DEVELOPED FLOWRATES
On-Site Historic Flowrates
On-Site Developed Flowrates (Undetained)
Odell Wine Project
F. Wegert
Area
Basin
2-Year
(cfs)
10-Year
(cfs)
February 12, 2020
10-Year
(cfs)
100-Year
(cfs)
On-Site Developed Flowrates (Detained)
Basin
Area 2-Year
(cfs)
10-Year
(cfs)
100-Year
(cfs)
Notes
Basin Notes
Area 2-Year
(cfs)
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
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
X
X
X
X
X
RD RD
X
X
D
G
G
CTV
CTV
CTV
E
E
E
E
T
T
AC
SS
SS
D
ST
ST
ST ST ST ST
ST ST ST
D
D
H
Y
D
W
C
S
VAULT
ELEC
CONTROL
IRR
CONTROL
IRR
CONTROL
IRR
CONTROL
CONTROL IRR
IRR
MH
VAULT
ELEC
VAULT
CABLE
VAULT
ELEC
D
D
D
C.O.
E
VAULT
X
X
X
X
X
X
X
D
G
G
T
AC
D
ST
ST
ST ST ST ST
ST ST ST
D
D
H
Y
D
W
C
S
VAULT
ELEC
CONTROL
IRR
CONTROL
IRR
CONTROL
IRR
CONTROL
CONTROL IRR
IRR
MH
VAULT
ELEC
VAULT
CABLE
VAULT
ELEC
D
D
D
C.O.
E
VAULT
ELEC
V.P.
ELEC
BRKR
E
GGG
C.O.
C.O.
AC
AC
M
Channel Report
Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Tuesday, Oct 15 2019
15-in HDPE Storm Sewer
Circular
Diameter (ft) = 1.25
Invert Elev (ft) = 4942.40
Slope (%) = 0.25
N-Value = 0.012
Calculations
Compute by: Known Q
Known Q (cfs) = 0.59
Highlighted
Depth (ft) = 0.35
Q (cfs) = 0.590
Area (sqft) = 0.28
Velocity (ft/s) = 2.08
Wetted Perim (ft) = 1.40
Crit Depth, Yc (ft) = 0.30
Top Width (ft) = 1.13
EGL (ft) = 0.42
0 1 2 3
Elev (ft)
Section
4941.50
4942.00
4942.50
4943.00
4943.50
4944.00
Reach (ft)
15" HDPE Upstream from Pavers
Basins OS1 & OS2 - 100-Year Storm
Channel Report
Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc. Wednesday, Jan 8 2020
15-in HDPE Storm Sewer with Flow from Pavers
Circular
Diameter (ft) = 1.25
Invert Elev (ft) = 4942.40
Slope (%) = 0.25
N-Value = 0.012
Calculations
Compute by: Known Q
Known Q (cfs) = 1.77
Highlighted
Depth (ft) = 0.63
Q (cfs) = 1.770
Area (sqft) = 0.62
Velocity (ft/s) = 2.85
Wetted Perim (ft) = 1.97
Crit Depth, Yc (ft) = 0.53
Top Width (ft) = 1.25
EGL (ft) = 0.76
0 1 2 3
Elev (ft)
Section
4941.50
4942.00
4942.50
4943.00
4943.50
4944.00
Reach (ft)
OS1, OS2 and Permeable Paver
Release Rate - 100-Year Storm
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
Q = 3 . 0 P H 1 . 5
Q = 0 . 67 A ( 2 gH ) 0 . 5
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
Discharge (cfs)
Stage (ft)
Stage - Discharge Curves
Weir Flow
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
Q = 3 . 0 P H 1 . 5
Q = 0 . 67 A ( 2 gH ) 0 . 5
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
Discharge (cfs)
Stage (ft)
Stage - Discharge Curves
Weir Flow
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
100-Year Design Flow = 0.58 cfs 10-Year Design Flow = 0.22 cfs
Q = 3 . 0 P H 1 . 5
Q = 0 . 67 A ( 2 gH ) 0 . 5
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
Discharge (cfs)
Stage (ft)
Stage - Discharge Curves
Weir Flow
Orifice Flow
Final Drainage Certification Memorandum
Date: February 3, 2014
Project: 2013 Odell Brew House Expansion Project No. 100-009
Fort Collins, Colorado
Attn: Mr. Glen Schlueter
City of Fort Collins – Stormwater Utility
700 Wood Street
Fort Collins, Colorado 80521
Dear Glen:
This memorandum serves to supplement the Commercial, Multi-Family and Subdivision
Certification Checklist, as published on the City of Fort Collins’ website. Specifically, it is intended
to document the modifications and current condition of the East Pond.
Due to the transplanting of several mature trees from the adjacent Link-N-Greens construction site,
as well as the presence of buried electrical lines and irrigation facilities, the East Pond fell short of
the required detention storage volume when initially surveyed for certification purposes. An
alternative design was subsequently developed, and vetted in the field with Wes Lamarque of Fort
Collins Stormwater.
While the pond was deficient in total volume, it met the requirements for site generated runoff from
Odell Brewing Co. The shortage was purely due to the off-site volume burden from Fort Collins
Monument and Stone (FCM&S). It is anticipated that FCM&S will construct their own detention
pond, thereby relieving the 2,554 cu.ft. of storage volume currently imposed on the Odell East
Pond. However, until said pond is built and certified, Odell will make an effort to provide the
interim volume, or increased water quality measures as an offset.
It is with those intentions in mind that the East Pond was modified after the aforementioned trees
were transplanted. The pond bottom was over-excavated two feet. 4-in. of topsoil was then
placed above 8-in. of sand, resulting in a nominal pond bottom approximately one foot lower than
the original design (4939.0 instead of 4940.0). This puts the pond bottom slightly below the
existing gravity outfall. While this is good from a low-impact development (LID) perspective, there
is a strong objective to minimize the potential depth and frequency of standing water. For these
reasons, a fourth dry well was added in addition to the sand bottom.
2013 Odell Brew House Expansion | Final Site Drainage Certification | 02.03.14
D:\Projects\100-009\Drainage\DrngCert\Odell_FinalDrngCertMemo_2014-02-03.docx Page 2 of 2
The permeable paver system was constructed pursuant to the approved plans and specifications.
This provides roughly 2,261 cu.ft. of LID detention storage in the sub-surface aggregate void
space. When combined with the 9,620 cu.ft. of open air detention volume, the East Pond
provides approximately 11,881 cu.ft. of total storage.
At this time it is kindly requested that the Temporary Certificate of Occupancy be switched to a
permanent Certificate of Occupancy given the substantial completion of the drainage
improvements. The attached Record Drawings and Checklist, as well as this memo, serve to
document the constructed condition. The slight shortage in detention volume in the East Pond is
not expected have adverse impacts to public health or safety. The additional trees and LID/water
quality benefits employed are viewed as positive offsets to the storage volume that will ultimately
reside on the FCM&S property.
The Overall Site Drainage Certification for the 2013 Odell Brew House is based upon field survey
information and site observation(s) conducted by Northern Engineering, as well as information and
testimony supplied by the General Contractor.
Please feel free to contact me if you have any questions.
Sincerely,
Nicholas W. Haws, PE, LEED AP
cc: Ben Basalay – RB+B Architects
Brian Cass – GH Phipps Construction Companies
enc.
02.03.14
Addendum to Final Drainage Certification Memorandum
Date: February 18, 2014
Project: 2013 Odell Brew House Expansion Project No. 100-009
Fort Collins, Colorado
Attn: Mr. Wes Lamarque
City of Fort Collins – Stormwater Utility
700 Wood Street
Fort Collins, Colorado 80521
Dear Wes:
This addendum letter is provided pursuant to your request to further document the interim volume
shortage in the East Pond. According to the 04.22.13 Drainage Addendum Letter for the Odell
Brewing Co. expansion applications (PDP120032 and MA130002), the required storage volume is
13,672 cu.ft. (11,118 cu.ft from Odell + 2,554 cu.ft. from Fort Collins Monument & Stone). The
volume currently provided (per the 02.03.14 Odell Record Drawings) is 11,881 cu.ft. (2,261
cu.ft. under the pavers + 9,620 cu.ft. in the open pond). This results in an interim volume
shortage of 1,791 cu.ft. (13,672 – 11,881).
According to recent soils reports (Terracon Proj. No. 20125035), infiltration rates of the native
soils range from 0.1 – 1 in/hr for upper lean clay and clayey sand soils to 2 – 6 in/hr for lower
sands and gravels. I chose to conservatively use 0.25 in/hr for infiltration at the installed dry wells.
There are four (4) dry wells, each 2 ft. diameter by 6 ft. deep. The total flow rate of all four dry
wells combined using an infiltration rate of 0.25 in/hr is 0.26 cfs. The estimated time to drain
1,791 cu.ft. of volume at 0.26 cfs is 1.9 hrs. Since the volume in question can theoretically be
drained in less than 2 hours, I feel the constructed pond remains adequate as-is.
Please feel free to contact me if you have any questions.
Sincerely,
Nicholas W. Haws, PE, LEED AP
02.18.14
CTV CTV CTV CTV CTV
CTV
CTV
T
X
D
ST ST ST
ST
ST
ST ST
ST ST ST
ST ST ST ST
ST
ST ST
ST ST ST ST
ST
D
MH
VAULT
CABLE
D
D
D
C.O.
V.P.
C.O.
C.O.
AC
AC
M
X
X
X
X
X X
X
X
X X
ST
ST
ST ST ST
UD UD
UD UD
0.54 ac.
A-1
0.17 ac.
OS-1
0.03 ac.
OS-2
0.19 ac.
0.25 ac. C
A-2
EAST POND
(EXISTING)
CONCRETE WALK
OUTDOOR PATIO
EXISTING CONCRETE APRON
EXISTING BUILDING
(824 E. LINCOLN AVE.)
ODELL BREWING
EXISTING OUTDOOR PATIO
EXISTING PARKING LOT
PERMEABLE
PAVERS
PERMEABLE
PAVERS
EXISTING SIDEWALK
EXISTING 327.12 LF OF 15" HDPE STORM SEWER S = 0.25%
0.01 ac.
B
0.02 ac.
OS-3
0.03 ac.
OS-5
0.01 ac.
OS-4
EXISTING
RETAINING WALL
EX. OVERHEAD
STRUCTURE
EXISTING
DOWNSPOUT (TYP.)
EXISTING BOLLARD (TYP.)
EXISTING VALLEY PAN
EXISTING STORM MH
RIM=4947.83 (RECORD)
INV IN=4943.22 (N)
INV OUT=4943.23 (S)
EXISTING STORM MH
RIM=4946.55
INV IN=4941.75 (W)
EXISTING OUTLET
STRUCTURE
EXISTING STORM MH
RIM=4946.20
INV IN=4942.08 (N)
INV IN=4942.12 (NE)
INV OUT=4942.01 (S)
EXISTING 22.74 LF
15" HDPE @ 0.92%
EXISTING STORM MH
RIM=4946.15
INV IN=4942.40 (N)
INV OUT=4942.33 (SW)
EXISTING 30.6 LF
18" HDPE @ 0.85%
a-1
b
os-1
os-2
a2
c
os-4
PROPOSED
RETAINING WALL
PROPOSED BRIDGE
PROPOSED
CLEANOUT (TYP.)
PROPOSED BOULDER WALL
(RE: LANDSCAPE ARCHITECT)
PROPOSED
VALLEY PAN
PROPOSED SWALE
PROPOSED INLET
CTV CTV CTV CTV CTV
CTV
CTV
T
X
D
ST ST ST
ST
ST
ST ST
ST ST ST
ST ST ST ST
ST
ST ST
ST ST ST ST
ST
D
MH
VAULT
CABLE
D
D
D
C.O.
V.P.
C.O.
C.O.
AC
AC
M
X
X
X
X
X X
X
X
X X
ST
ST
ST ST ST
W
W
W W
W
EAST POND
(EXISTING)
EXISTING CONCRETE APRON
EXISTING BUILDING
(824 E. LINCOLN AVE.)
ODELL BREWING
EXISTING OUTDOOR PATIO
EXISTING PARKING LOT
EXISTING SIDEWALK
EXISTING 327.12 LF OF 15" HDPE STORM SEWER S = 0.25%
0.42 ac.
HB
0.57 ac.
HA
0.03 ac.
HOS4
0.17 ac.
HOS1
0.03 ac.
HOS2
0.03 ac.
HOS3
EXISTING
RETAINING WALL
EX. OVERHEAD
STRUCTURE
EXISTING
DOWNSPOUT (TYP.)
EXISTING BOLLARD (TYP.)
EXISTING VALLEY PAN
EXISTING STORM MH
RIM=4947.83 (RECORD)
INV IN=4943.22 (N)
INV OUT=4943.23 (S)
EXISTING STORM MH
RIM=4946.55
INV IN=4941.75 (W)
EXISTING OUTLET
STRUCTURE
EXISTING STORM MH
RIM=4946.20
INV IN=4942.08 (N)
INV IN=4942.12 (NE)
INV OUT=4942.01 (S)
EXISTING 22.74 LF
15" HDPE @ 0.92%
EXISTING STORM MH
RIM=4946.15
INV IN=4942.40 (N)
INV OUT=4942.33 (SW)
EXISTING 30.6 LF
18" HDPE @ 0.85%
hb
hos3
hos1
hos2
ha
Sheet
ODELL WINE PROJECT These drawings are
instruments of service
provided by Northern
Engineering Services, Inc.
and are not to be used for
any type of construction
unless signed and sealed by
a Professional Engineer in
the employ of Northern
Engineering Services, Inc.
NOT FOR CONSTRUCTION
REVIEW SET
E NGINEER ING
N O R T H E RN
FORT COLLINS: 301 North Howes Street, Suite 100, 80521
GREELEY: 820 8th Street, 80631
970.221.4158
northernengineering.com
of 12
( IN FEET )
0
1 INCH = 20 FEET
20 20 40 60
NORTH
CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOU
DIG, GRADE, OR EXCAVATE FOR THE MARKING OF
UNDERGROUND MEMBER UTILITIES.
CALL UTILITY NOTIFICATION CENTER OF
COLORADO
Know what'sbelow.
Call before you dig.
R
C603
DRAINAGE EXHIBIT
13
LEGEND:
PROPOSED CONTOUR
PROPOSED STORM SEWER
PROPOSED SWALE
EXISTING CONTOUR
PROPERTY BOUNDARY
DESIGN POINT A
FLOW ARROW
DRAINAGE BASIN LABEL
DRAINAGE BASIN BOUNDARY
PROPOSED SWALE SECTION
1 1
B2
1.45 ac
PROPOSED AREA DRAIN INLET
PROPOSED UNDERDRAIN UD
HISTORIC BASIN BOUNDARIES DEVELOPED BASIN BOUNDARIES
DEVELOPED DRAINAGE SUMMARY
Design
Point Basin ID
Total
Area
(acres)
C2 C100
2-Yr Tc
(min)
100-Yr Tc
(min)
Q2
(cfs)
Q100
(cfs)
a-1 A-1 0.536 0.75 0.94 9.91 9.91 0.91 4.86
a-2 A-2 0.255 0.57 0.71 11.64 11.64 0.30 1.37
b B 0.012 0.20 0.25 5.69 5.69 0.01 0.03
c C 0.190 0.43 0.54 10.13 10.13 0.18 0.82
os-1 OS-1 0.174 0.27 0.34 8.02 8.02 0.11 0.50
os-2 OS-2 0.035 0.20 0.25 6.23 6.23 0.02 0.08
os-3 OS-3 0.017 0.20 0.25 5.00 5.00 0.01 0.04
os-4 OS-4 0.011 0.67 0.83 5.00 5.00 0.02 0.09
os-5 OS-5 0.030 0.43 0.54 5.00 5.00 0.04 0.16
HISTORIC DRAINAGE SUMMARY
Design
Point Basin ID
Total
Area
(acres)
C2 C100
2-Yr Tc
(min)
100-Yr Tc
(min)
Q2
(cfs)
Q100
(cfs)
ha HA 0.573 0.67 0.84 11.16 11.16 0.82 4.14
a1 HB 0.420 0.61 0.77 5.18 5.18 0.73 3.20
hos1 HOS1 0.174 0.20 0.25 8.48 8.48 0.08 0.36
a3 HOS2 0.035 0.20 0.25 6.23 6.23 0.02 0.08
hos3 HOS3 0.028 0.35 0.44 7.05 7.05 0.02 0.11
a5 HOS4 0.030 0.42 0.52 5.00 5.00 0.04 0.15
DETENTION POND SUMMARY
Pond ID
Volume
(cu. ft.) WSEL
Release
Rate (cfs)
Permeable Pavers 2,515 4946.39 1.19
Orifice Flow
Assumes permeable pavers are 100% clogged.
Orifice Flow
Assumes permeable pavers are 100% clogged.
G
G
G
G
ST
VAULT
ELEC
EXISTING
DRAINAGE
EASEMENT
PROPOSED
DRAINAGE
EASEMENT
PERMEABLE PAVERS
(SOLID AREA)
P:\100-020\DWG\DRNG\100-020_DRAINAGE EASEMENT.DWG
824 E. LINCOLN AVENUE
FORT COLLINS
COLORADO
Fort Collins: 301 N. Howes St., Ste. 100, 80521
Greeley: 820 8th Street, 80631
ENGINEER ING
N O R T H E RN
PHONE: 970.221.4158
www.northernengineering.com
DESCRIPTION
DRAINAGE EASEMENTS
DRAWN BY
F. WEGERT
DATE
FEBRUARY 12, 2020
PROJECT
100-020 DR-C2
SCALE DRAWING
1"=50'
ELEC
V.P.
ELEC
BRKR
E
GGG
C.O.
C.O.
AC
AC
M
G
G
G
G
E
E
E
E
E
E
X
T
T T
X
T
T
T
T
ST
SS
SS
SS
VAULT
ELEC
E
E
E
E
E
E
PROPOSED
CONCRETE
PROPOSED
GRAVEL
EXISTING
CONCRETE
EXISTING
ROOF
P:\100-020\DWG\DRNG\100-020_LID.DWG
824 E. LINCOLN AVENUE
FORT COLLINS
COLORADO
Fort Collins: 301 N. Howes St., Ste. 100, 80521
Greeley: 820 8th Street, 80631
ENGINEER ING
N O R T H E RN
PHONE: 970.221.4158
www.northernengineering.com
DESCRIPTION
NEW IMPERVIOUS AREA
AND LID TREATMENT
DRAWN BY
F. WEGERT
DATE
FEBRUARY 12, 2020
PROJECT
100-020 DR-C1
SCALE DRAWING
1"=50'
PAVERS
LID TREATMENT OF
IMPERVIOUS AREAS
PROPOSED
CONCRETE
NEW IMPERVIOUS AREA
NOT TREATED BY LID
2,881 ft2
662 ft2
1,405 ft2
4,092 ft2
2,986 ft2
TOTAL TREATED 9,040 ft
2
NEW IMPERVIOUS
AREA TREATED 5,497 ft
2
1,718 ft2
NEW IMPERVIOUS
AREA NOT TREATED 1,718 ft
2
AREA REQUIRING LID (2015):
AREA REQUIRING LID (2020):
TOTAL AREA REQUIRING LID:
TOTAL IMPERVIOUS AREAS
RECEIVING LID TREATEMENT:
RUN ON AREA / TREATMENT AREA:
1,573 FT2
7,215 FT2
8,788 FT2
9,040 FT2
3.0
C =
Design Storm
Page 1 of 1
100-020_Pond_FAA.xls
FEBRUARY 12, 2020
PROJECT
100-020 DR-A1
SCALE DRAWING
1"=50'
LANDSCAPE 10,184 0% 0 LANDSCAPE 14,177 0% 0
9,645
8,645
2,711
9,589
11,726
9,589
100-Yr
(min)
a-1 A-1 143 47.72 46.11 1.13% 7.4 7.4 3.4 N/A N/A N/A 126 46.11 45.71 0.32% 0.85 2.48 11.49 9.91 11.49 9.91 11.49 5.86
a-2 A-2 125 47.50 45.91 1.27% 10.2 10.2 7.5 N/A N/A N/A 170 45.91 45.35 0.33% 0.86 3.29 11.64 11.64 11.64 11.64 11.64 10.79
b B 25 46.30 45.39 3.64% 5.5 5.5 5.2 N/A N/A N/A 35 45.39 44.31 3.09% 2.63 0.22 10.33 5.69 10.33 5.69 10.33 5.39
c C 35 47.50 47.00 1.43% 6.6 6.6 5.5 N/A N/A N/A 225 47.00 45.88 0.50% 1.06 3.54 11.44 10.13 11.44 10.13 11.44 9.07
os-1 OS-1 69 56.00 47.50 12.32% 5.6 5.6 5.1 N/A N/A N/A 100 47.50 47.29 0.21% 0.69 2.42 10.94 8.02 10.94 8.02 10.94 7.57
os-2 OS-2 69 56.00 47.50 12.32% 6.1 6.1 5.7 N/A N/A N/A 23 47.50 47.00 2.17% 2.21 0.17 10.51 6.23 10.51 6.23 10.51 5.89
os-3 OS-3 20 46.54 45.39 5.75% 4.2 4.2 4.0 N/A N/A N/A 35 45.39 44.31 3.09% 2.63 0.22 10.31 5.00 10.31 5.00 10.31 5.00
os-4 OS-4 25 46.45 45.58 3.48% 2.7 2.7 1.6 N/A N/A N/A N/A N/A N/A 10.14 5.00 10.14 5.00 10.14 5.00
os-5 OS-5 10 45.77 45.58 1.90% 3.2 3.2 2.7 N/A N/A N/A N/A N/A N/A 10.06 5.00 10.06 5.00 10.06 5.00
a-1 A-B 125 47.50 45.91 1.27% 8.0 8.0 4.7 N/A N/A N/A 317 45.91 39.00 2.18% 2.21 2.39 12.46 10.35 12.46 10.35 12.46 7.04
a-1 Pavers 125 47.50 45.91 1.27% 9.4 9.4 6.4 N/A N/A N/A 126 46.11 45.71 0.32% 0.85 2.48 11.39 11.39 11.39 11.39 11.39 8.93
a-1 A-OS1 69 56.00 47.50 12.32% 3.6 3.6 2.7 N/A N/A N/A 327 43.22 42.40 0.25% 0.75 7.26 12.20 10.87 12.20 10.87 12.20 9.92
c C-OS2 69 56.00 47.50 12.32% 4.8 4.8 4.1 N/A N/A N/A 225 47.50 44.31 1.42% 1.79 2.10 11.63 6.85 11.63 6.85 11.63 6.19
Velocity (Gutter Flow), V = 20·S½
Rational Equation: Q = CiA (Equation 6-1)
Intensity, i (per Table 3.4-1 of the Fort Collins Stormwater Manual)
Velocity (Swale Flow), V = 15·S½
Odell Wine
F. Wegert
February 12, 2020
DEVELOPED TIME OF CONCENTRATION COMPUTATIONS
Overland Flow, Time of Concentration:
Gutter/Swale Flow, Time of Concentration:
Tt = L / 60V (Equation 6-4 per MHFD)
Tc = Ti + Tt (Equation 6-2 per MHFD)
Combined Basins
Channelized Flow Swale Flow
Design
Point
Basin
Overland Flow Time of Concentration
(Equation 6-4 per MHFD)
(Equation 3.3-2 per Fort Collins
}
𝑇𝑖 =
1.87 1.1 − 𝐶 ∗ 𝐶𝑓 𝐿
𝑆 ൗ
1
3
Notes:
1) Add 4900 to all elevations.
Page 1 of 1
Streets, Parking Lots, Roofs, Alleys, and Drives:
Lawns and Landscaping:
Combined Basins
2) Composite Runoff Coefficient adjusted per Table 3.2-3 of the Fort Collins
Stormwater Manual (FCSM).
Lawns, Clayey Soil, Flat Slope < 2%
USDA SOIL TYPE: C
Lawns, Sandy Soil, Flat Slope < 2% Composite Runoff Coefficient2
1) Runoff coefficients per Tables 3.2-1 & 3.2 of the FCSM. Percent impervious per Tables 4.1-2 & 4.1-3 of the FCSM.
Page 1 of 1
100-Yr
(min)
ha HA 147 48.00 45.91 1.42% 8.6 8.6 5.2 N/A N/A N/A 248 45.91 43.00 1.18% 1.63 2.54 12.19 11.16 12.19 11.16 12.19 7.77
a1 HB 15 47.50 47.00 3.33% 2.4 2.4 1.6 N/A N/A N/A 257 47.00 44.38 1.02% 1.51 2.83 11.51 5.18 11.51 5.18 11.51 5.00
hos1 HOS1 69 56.00 47.50 12.32% 6.1 6.1 5.7 N/A N/A N/A 100 47.50 47.29 0.21% 0.69 2.42 10.94 8.48 10.94 8.48 10.94 8.14
a3 HOS2 69 56.00 47.50 12.32% 6.1 6.1 5.7 N/A N/A N/A 23 47.50 47.00 2.17% 2.21 0.17 10.51 6.23 10.51 6.23 10.51 5.89
hos3 HOS3 40 46.45 45.60 2.13% 6.9 6.9 6.1 N/A N/A N/A 30 45.60 44.38 4.07% 3.02 0.17 10.39 7.05 10.39 7.05 10.39 6.24
a5 HOS4 25 45.84 43.00 11.36% 2.8 2.8 2.4 N/A N/A N/A N/A N/A N/A 10.14 5.00 10.14 5.00 10.14 5.00
Channelized Flow Swale Flow
Design
Point
Basin
Overland Flow Time of Concentration
Velocity (Gutter Flow), V = 20·S½
Rational Equation: Q = CiA (Equation 6-1)
Intensity, i (per Table 3.4-1 of the Fort Collins Stormwater Manual)
Velocity (Swale Flow), V = 15·S½
Odell Wine
F. Wegert
February 12, 2020
HISTORIC TIME OF CONCENTRATION COMPUTATIONS
Overland Flow, Time of Concentration:
Gutter/Swale Flow, Time of Concentration:
Tt = L / 60V (Equation 6-4 per MHFD)
Tc = Ti + Tt (Equation 6-2 per MHFD)
(Equation 6-4 per MHFD)
(Equation 3.3-2 per Fort Collins
}
𝑇𝑖 =
1.87 1.1 − 𝐶 ∗ 𝐶𝑓 𝐿
𝑆 ൗ
1
3
Notes:
1) Add 4900 to all elevations.
Page 1 of 1
Calculations By:
Date:
Character of Surface
Streets, Parking Lots, Roofs, Alleys, and Drives:
Page 1 of 1