HomeMy WebLinkAboutDrainage Reports - 09/04/2013 (2)Plans
C4',of`FL CON p ed
Approved By
NORTHERN
i EN.GINEE.RING
Drainage Letter Report
I
Date: March 26, 2013
ADDRESS: PHONE: 970.22L 158
200 S. College Ave. Suite 10 WEBSITE:
fort Collins, CO80524 FAX:1970.221.4159 www.northernengineering.com
Project: Northside Aztlan Community Center Project No. 207-008
Minor Amendment
Fort Collins, Colorado
Attn: Mr. Wes Lamarque
City of Fort Collins Stormwater Utility
700 Wood Street
Fort Collins, Colorado 80521
Dear Wes:
This letter serves to address the stormwater impacts of the Northside Aztlan Community Center Minor -
Amendment. The site is located within Lot 1 of the Northside Aztlan Community Center. More
specifically, the portion of land within Lot 1 located west of the existing Burlington Northern Railroad and
Right-of-way. The tract of land currently acts as a regional detention facility for approximately 14.6 acres.
The property is bounded by an.Express Lube and Center for Fine Art & Photography to the west, Burlington
northern Railroad to the North and East and Willow Street to the South.
Through discussion with the City, it was agreed upon that the area routed to the existing detention pond
would be modeled. This Hydrologic modeling for the existing detention area was done using the computer
program EPA SWMM 5. EPA SWMM 5 is a windows -based version of the Environmental Protection
Agency's (EPA) Storm Water Management Model with a graphic user interface.
As shown in the Overall SWMM Exhibit provided in the attachments, the existing detention area receives
storm runoff from a larger area than simply the proposed parking lot addition. Approximately 14.96 acres
extending from LaPorte Avenue to Cherry Street along the west side of College Avenue drain to the existing
detention area. This area was identified in the study, "Drainage Study for the North College Avenue
Improvements", by Felsburg Holt & Ullevig, dated May 9, 2003. In addition to this area, approximately
4.49 acres encompassing an area between Jefferson Street and the Burlington Northern Railroad Right of
Way also drains to the existing detention area.
The existing detention area drains to the Cache La Poudre River located just north of the proposed parking
lot addition. There is a 9.5-foot diameter manhole with an open top and. custom grate which serves as the
primary outlet for the existing detention area. The rim elevation of this manhole is at 4965.67, which
allows a very large release rate from the existing detention area. The manhole is connected to a 48-inch
storm line draining to the Cache La Poudre River. In addition to this manhole, there is an 18-inch storm
line stubbed out of an upstream manhole just south of the 9.5-foot diameter manhole. This storm line
currently serves to drain the existing low lying area of the detention area. The proposed plan shows a
water quality plate -and headwall being added to the 18-inch line in order to create water quality capture
JbRni1 ^nii fi;i .Bl f'� Y!?ic_JJi
fi`HRIP,G ,.l hJrV "n-'1"
volume. Thus, in the proposed condition, the 9.5-foot diameter manhole will serve as the primary
detention outlet.
The SWMM model created for this project incorporates the overall basins draining to thle existing detention
area. Timing of hydrograph peaks within the existing storm line system are accounted for, resulting in the
following results for the existing detention area.
POND
PEAK
PEAK
WATER
TOTAL
100-YEAR
100-YEAR
100-YEAR
QUALITY
POND
WATER SURFACE
STORAGE
DISCHARGE
CAPTURE VOL.
VOLUME
ELEVATION
(AC -FT)
(CFS)
(AC -FT)
(AC -FT)
(FT)
Existing
Detention
Area
0.171
31.8
0.006
0.177
4966.30
Please see the attachments SWMM Exhibit, SWMM Schematic, pond rating curves, and SWMM model
output. ,
The proposed redevelopment will include the construction of 44 parking spaced with associated landscape
islands. The proposed parking area will encroach into the western property owned by Superior Lube, Inc.
All stormwater from the site will be routed via overland flow and gutter flow and discharged into the
existing pond at three curb cut locations. These discharge location have been individually sized and are
shown within the attachments.
To account for water quality, a drain time of 40 hours was used to establish a Water Quality Capture
Volume (WQCV) of 0.006 ac-ft. This WQCV is established at an elevation of 4965.2 feet. A perforated
orifice plate is designed to control this water quality volume. In maintaining the existing configuration of
the detention pond, the current volume allowed before overtopping is 1.17 acre feet. On the chance that
both inlets clog, the stormwater will over top the railroad to the east and enter into a swale that was
designed within Northside Aztlan Center and into the same existing storm sewer.
An Erosion and Sediment Control Plan (along with associated details) is included with the construction
drawings. It should be noted that this Erosion and Sediment Control Plan serves only as a general guide to
the Contractor. Staging and/or phasing of the BMPs depicted, and additional or different BMPs from those
shown may be necessary during construction, or as required by the authorities having jurisdiction.
It shall be the responsibility of the Contractor to ensure erosion control measures are properly maintained
and followed. The Erosion and Sediment Control Plan is intended to be a living document, constantly
adapting to site conditions and needs. The Contractor shall update the location of BMPs as they are
installed, removed or modified in conjunction with construction activities. It is imperative to appropriately
reflect the current site conditions at all times.
The plan addresses both temporary measures to be implemented during construction, as well as
permanent erosion control protection. Best Management Practices (BMPs) from the UDFCD will be
utilized. Among the measures expected are: gutter protection in the adjacent roadways and inlet
protection at the existing and proposed storm drains. Vehicle tracking control pads, spill containment and
clean-up procedures, and designated concrete washout areas shall also be provided by the Contractor. A
■V NORTHERN
ENGINEERING
Stormwater Management Plan and Stormwater Discharge Permit will be required prior to construction.
The contractor should refer to current state requirements at time of construction.
i I I
The drainage design proposed with the Northside Aztlan Community Center Minor Amendment project
complies with the City of Fort Collins' Stormwater Criteria Manual. The drainage design proposed complies
with the City of Fort Collins' Master Drainage Plan.for the Foothills Drainage Basin. There is no FEMA
100-year regulatory floodplain within the site. The drainage plan and stormwater management measures
proposed with this project are compliant with all applicable State and Federal regulations governing
stormwater discharge.
The drainage design proposed the Northside Aztlan Community Center Minor Amendment project will
effectively limit any potential damage or erosion associated with its stormwater runoff by providing a water
quality pond that will service the proposed parking area and existing facilities located west of the site. The
proposed Northside Aztlan Community Center Minor Amendment will not have any impact on the Master
Drainage Plan recommendations for the Cache La Poudre River Drainage Basin.
Please do not hesitate to contact me if you have questions or require additional information.
Sincerely, r
Nicholas W. Haws, PE. LEED
Project Manager AP
Cod Snowdon
Project Engineer
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3/26/2013 Northern Engineering Services, Inc. 207-008 Broad -Crested Weir.xls
By: CNS Northside Aztlan Community Center Minor Amendment p1 Curb Cut
Project No. 207-008
Broad -Crested Weir: P1 Curb Cut
Project: Northside Aztlan Community Center Minor Amendment
Design: CNS
Project # 207-008
Governing Equations:
If the weir is long in the direction of flow so that the flow leaves the weir in essentially a horizontal direction, the weir is a broad -
crested weir. Reference 1) "Hydraulic Engineering, Roberson, Cassidy & Chaudhry., John Wiley & Sons, 1995, pg 212)"
Q= 0.385CiLV 2g H-
• where Q is flow rate in CFS
- where C is ratio of actual discharge to theoretical discharge.
A value of C can be obtained from Figure 4-36 of Reference 1.
" where L is the crest length of the weir (F7)
" where H is the height of flow over the crest (F7)
" where P is the vertical distance from weir crest to pondlchannel invert (F7)
Broad -Crested Weir Coefficient (C)
fir+
L
V um
S
H }
f BROAD -CRESTED
Ow
0 0.2 o.a oa na t
WEM
HI(H+P)
'-------._;----.___.
Valid if 0.1<H/L<0.8
Input Parameters:
Length (L)= 2.00
FT
Crest Elevation = 4970,06
FT
Upsteam Invert Elevation= 4970.06
FT
Q10 = 1.2
CFS
Q10, = 2.7
CFS
Depth vs. Flow:
Depth Above Elevation
Flow
CHECK
Crest (ft) (ft) H/(H+P)
C
cfs
H/L
0.00 4970.06 NA
NA
NA
NA
0.10 4970.16 1.00
1.31
0.26
INVALID
0.20 4970.26 1.00
1.31
0.72
INVALID
0.30 4970.36 1.00
1.31
1.33
0.150
0.40 4970,46 1.00
1.31
2.05
0.200
0.48 4970.54 1.00
1.31
2.70 4-- Q100
0.240
0.50 4970.56 1.00
1.31
2.86
0.250
0.60 4970.66 1.00
1.31
3.76
0.300
0.70 4970.76 1.00
1.31
4.74
0.350
0.80 4970.86 1.00
1.31
5.79
0.400
0.90 4970.96 1.00
1.31
6.91
0.450
1.00 4971.06 1.00
1.31
8.10
0.500
Page 1 of 3
3/26/2013 Northern Engineering Services, Inc. 207-008 Broad -Crested Weir.xls
By: CNS Northside Aztlan Community Center Minor Amendment p2 Curb Cut
Project No. 207-008
Broad -Crested Weir: P2 Curb Cut
Project: Northside Aztlan Community Center Minor Amendment
Design: CNS
Project # 207-008
Governing Equations:
If the weir is long in the direction of flow so that the flow leaves the weir in essentially a horizontal direction, the weir is a broad -
crested weir. Reference 1) "Hydraulic Engineering, Roberson, Cassidy 8 Chaudhry., John Wiley 8 Sons, 1995, pg 212)"
Q= o.385 CL� 2g H V2
' where Q is flow rate in CFS
` where C is ratio of actual discharge to theoretical discharge. A value of C can be obtained from Figure 4-36 of Reference 1.
' where L is the crest length of the weir (FT)
' where H is the height of flow over the crest (FT)
' where P is the vertical distance from weir crest to pondlchannel invert (FT)
Broad -Crested Weir Coefficient (C)
F
L
IT
09
` H
0.a9
0 9.2 04 06 9.e ,
BROALL-CRESrED
H/(H+P)
,.'-WEIR
----..- ---------- -----
Valid if 0.1 <H/L<0.8
Input Parameters:
Length (L)= 2.00 FT
Crest Elevation = 4970.06 FT
Upsteam Invert Elevation= 4970.06 FT
Q10 = 1.6 CFS
Q100 = 3.7 CFS
Depth vs. Flow:
Depth Above Elevation
Flow
CHECK
Crest (ft) (ft) H/(H+P) C
cfs
H/L
0.00 4970.06 NA NA
NA
NA
0.10 4970.16 1.00 1.31
0.26
INVALID
0.20 4970.26 1.00 1.31
0.72
INVALID
0.30 4970.36 1.00 1.31
1.33
0.150
0.40 4970.46 1.00 1.31
2.05
0.200
0.50 4970.56 1.00 1.31
2.86
0.250
0.59 4970.65 1.00 1.31
3.70 -4- Q1oo
0.297
0.60 4970.66 1.00 1.31
3.76
0.300
0.70 4970.76 1.00 1.31
4.74
0.350
0.80 4970.86 1.00 1.31
5.79
0.400
0.90 4970.96 1.00 1.31
6.91
0.450
1.00 4971.06 1.00 1.31
8.10
0.500
Page 2 of 3
3/26/2013 Northern Engineering Services, Inc. 207-008 Broad -Crested Weir.xls
By: CNS Northside Aztlan Community Center Minor Amendment p3 Curb Cut
Project No. 207-008
Broad -Crested Weir: P2 Curb Cut
Project: Northside Aztlan Community Center Minor
Amendment
Design: CNS
Project # 207-008
Governing Equations:
If the weir is long in the direction of flow so that the flow leaves the weir in essentially a horizontal direction, the weir is a broad -
crested weir. Reference 1) "Hydraulic Engineering, Roberson, Cassidy & Chaudhry., John
Wiley & Sons, 1995, pg 212)"
Q= 0,385 CL� 2g H 3/2
' where Q is flow rate in CFS
- where C is ratio of actual discharge to theoretical discharge.
A value of C can be obtained from Figure 4-36 of Reference 1.
` where L is the crest length of the weir (FT)
' where H is the height of flow over the crest (FT)
• where P is the vertical distance from weir crest to pondlchannel invert (FT)
Broad -Crested Weir Coefficient (C)
os
U
09
N J
_ ...
P I BROAD -CRESTED
�,,
n2 04 os "1 t
ffls'
H/(H+P)
---.t.._i------ -------- -.--- ___�............. .___......
Valid if 0.1<H/L<0.8
Input Parameters:
Length (L)= 2.00
FT
Crest Elevation = 4970,06
FT
Upsteam Invert Elevation= 4970.06
FT
Ole = 3.2
CFS
0100 = 7.6
CFS
Depth vs. Flow:
Depth Above Elevation
Flow
CHECK
Crest (ft) (ft) H/(H+P)
C
cfs
H/L
0.00 4970.06 NA
NA
NA
NA
0.10 4970.16 1.00
1.31
0.26
INVALID
0.20 4970.26 1.00
1.31
0.72
INVALID
0.30 4970.36 1.00
1.31
1.33
0.150
0.40 4970.46 1.00
1.31
2.05
0.200
0.50 4970.56 1.00
1.31
2.86
0.250
0.59 4970.65 1.00
1.31
3.70
0.297
0.60 4970.66 1.00
1.31
3.76
0.300
0.70 4970.76 1.00
1.31
4.74
0.350
0.80 4970.86 1.00
1.31
5.79
0.400
0.90 4970.96 1.00
1.31
6.91
0.450
0.96 4971.02 1.00
1.31
7.60 -- Q100
0.479
1.00 4971.06 1.00
1.31
8.10
0.500
Page 3 of 3
-- SWMM Appendix
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PROJECT OUTFALLS VIA
-
EXISTING STORM SYSTE
TO CACHE LA POUDRE
C16
IVER
I I C15
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II C14
-GEND
SWMM BASIN 1
OVERALL BASIN IDENTI
C1 C ND I
IN "DRAINAGE STUDY OR
THE NORTH COLLEGE �jVE.
ENTS, 8Y I
P1 '
11
LSBURG H
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NOR
NORTHERN
SWMM SCHEMATIC
DRAWN BY: A.CVAR
SHEET NO:
ENGINEERING
200 South College Avenue. Su
10 HONE: 970.221.4158 FAX: 970.221.4158
SCALE: NTS
ISSUED: 2/1/13
Fort Collins, Colorado 80524 www.northemenglnsering.eom
SWMM RATING CURVE
Existing Detention Area
Project: 207-008
Date: 2.7.13 ( ( I
By: ATC
Required Water Quality Capture Volume:
.006 ac-ft (M cu.ft.) of Water Quality Capture Volume Req'd
I I I
STAGE
FT
DEPTH
FT
SURFACE AREA
OF CONTOUR
SF
STORAGE
CF
STORAGE
AC -FT
RELEASE
CFS
4,963.40
0
0.15
0
0.000
0.00
4,964.00
0.60
10.56
2.13
0.000
0.00
4,965.20
1.80
688.11
289.91
0.007
0.00
4,966.00
2.60
6,131.24
2594.59
0.060
8.50
4,967.00
3.60
29,219.38
19688.73
0.452
66.70
Area Inlet Performance Curve:
Manhole ID: Existing Detention Area Outlet (9.5' dia. manhole.with custom grate)
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 1 5
• where H corresponds to the depth of water above the flowline IQ 3 • O P H
At higher Flow depths, the inlet will act like an orifice governed by the following equation: 1_ O . 67 A Z gH ) 0.5
' 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)
I
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:
t Weir Flow
t—Orifice Flow
If H > 1.792 (Afl, then the grate operates like an orifice; otherwise it operates like a weir.
Input Parameters:
Type of Grate:
PERFORATED MANHOLE COVER
Diameter of Grate (ft):
9.5
Open Area of Grate (ftZ):
56.70
Flowline Elevation (ft):
4965.670
Reduction Factor:
50%
Depth vs. Flow:
Shallow
Orifice
Actual
Elevation
Weir Flow
Flow
Flow
Depth Above Inlet (ft)
(ft)
(cfs)
(cfs)
(cfs)
0.00
4965.67
0.00
0.00
0.00
0.33
4966.00
8.49
87.52
8.49
0.83
4966.50
33.85
138.81
33.85
1.33
4967.00
68.67
175.71
68.67
EPA STORM WATER MANAGEMENT MODEL - VERSION 5.0 (Build 5.0.022)
--------------------------------------------------------------
++++++++++++xxxxxxxxxxx+++++++x+++++xxxxxxx+++++++++RR+++
NOTE: The summary statistics displayed in this report are
based on results found at every computational time step,
not just on results from each reporting time step.
++++++++++++++++
Analysis Options
Flow Units ...............
CFS
Process Models:
Rainfall/Runoff ........
YES
Snowmelt ...............
NO
Groundwater ............
NO
Flow Routing ...........
YES
Ponding Allowed ........
NO
Water Quality ..........
NO
Infiltration Method ......
HORTON
Flow Routing Method ......
KINWAVE
Starting Date ............
APR-22-2011 00:00:00
Ending Date ..............
APR-22-2011 06:00:00
Antecedent Dry Days ......
0.0
Report Time Step .........
00:15:00
Wet Time Step ............
00:05:00
Dry Time Step ............
01:00:00
Routing Time Step ........
30.00 sec
WARNING 08: elevation drop exceeds length for Conduit 5
WARNING 08: elevation drop exceeds length for Conduit 9
WARNING 02: maximum depth increased for Node 6
WARNING 02: maximum -depth increased for Node 8
**************************
Volume
Depth
Runoff Quantity Continuity
+RxRRRRRR++Y++++++++hRRRRR
acre-feet
inches
Total Precipitation ......
5.947
3.669
Evaporation Loss .........
0.000
0.000
Infiltration Loss ........
0.089
0.055
Surface Runoff ...........
5.837
3.601
Final Surface Storage ....
0.059
0.036
Continuity Error (8) .....
-0.627
**************************
Volume
Volume
Flow Routing Continuity
++++++++++RRRRR+++++++x+++
acre-feet
10^6 gal
Dry Weather Inflow .......
---------
0.000
---------
0.000
Wet Weather Inflow .......
5.837
1.902
Groundwater Inflow .......
0.000
0.000
RDII Inflow ..............
0.000
0.000
External Inflow ..........
0.000
0.000
External Outflow .........
4.829
1.573
Internal Outflow .........
0.993
0.323
Storage Losses ...........
0.000
0.000
Initial Stored Volume ....
0.000
0.000
Final Stored Volume ......
0.010
0.003
Continuity Error (o) .....
0.106
Highest Flow Instability Indexes
SWMM 5 Page 1
Link 10 (2)
Link 9 (1)
Link 16 (1)
i
Routing Time Step Summary
i)
Minimum Time Step
30.00 sec
Average Time Step
30.00 sec
Maximum Time Step
30.00 sec
Percent in Steady State
0.00
Average Iterations per Step
1.53
Subcatchment Runoff Summary
---------------------------------
Total
Total
Total
-------------------------------
Total
Total
Total
Peak
-
Runoff
Precip
Runon
Evap
Infil
Runoff
Runoff
Runoff
Coeff
Subcatchment
in
in
in
in
in
10^6 gal
CFS
---------------------
1
3.67
---------------------------------------------------------------------
0.00
0.00
0.05
3.60
1.46
147.59
0.982
2
3.67
0.00
0.00
.0.05
3.60
0.44
44.30
0.982
Node Depth Summary
--------------------------------------
Average Maximum Maximum Time of Max
Depth
Depth
HGL
Occurrence
Node
Type
Feet
Feet
Feet
days
hr:min
------------------------
4
JUNCTION
---------------------------------
0.45
1.74
60.49
0
00:34
7
JUNCTION
0.43
1.65
65.85
0
00:33
9
JUNCTION
0.51
2.01
64.41
0
00:33
10
JUNCTION
0.51
2.01
63.12
0
00:34
11
JUNCTION
0.41
1.89
52.06
0
00:46
5
OUTFALL
0.41
1.89
51.23
0
00:40
6
DIVIDER
0.32
1.15
66.64
0
00:22
8
DIVIDER
0.30
1.56
66.56
0
00:32
3
STORAGE
1.78
3.00
12.00
0
00:47
*******************
Node Inflow Summary
*******************
Maximum
Maximum
Lateral
Total
Lateral
Total
Time
of Max
Inflow
Inflow
Inflow
Inflow
Occurrence
Volume
Volume
Node
-------------------------------------------------------------------------------------
Type
CFS
CFS
days
hr:min
10^6 gal
10^6 gal
4
JUNCTION
0.00
73.78
0
00:46
0.000
1.575
7
JUNCTION
0.00
42.05
0
00:33
0.000
1.247
9
JUNCTION
0.00
42.05
0
00:33
0.000
1.247
10
JUNCTION
0.00
42.03
0
00:34
0.000
1.246
11
JUNCTION
0.00
73.78
0
00:46
0.000
1.574
5
OUTFALL
0.00
73.78
0
00:40
0.000
1.573
6
DIVIDER
147.59
147.59
0
00:40
1.463
1.463
8
DIVIDER
44.30
44.30
0
00:40
0.439
0.439
3
STORAGE
0.00
149.89
0
00:40
0.000
0.656
++++++++++++++++++++++
Node Surcharge Summary
SWMM 5 Page 2
No nodes were surcharged.
Node Flooding Summary
Flooding refers to all water that overflows a node, whether it ponds or not
Total
Maximum
Maximum
Time of Max
Flood
Ponded
Hours Rate
Occurrence
Volume
Volume
Node Flooded CFS -
days hr:min
10^6 gal
1000 ft3
-----------------------------------------
3 0.21 113.73
0 00:40
-------------
0.323
0.000
Storage Volume Summary
*****«««*««x##x###++++
---------------------------------------------------------------------
Average
Avg
E&I
Maximum
Max
Time of Max
Maximum
Volume
Pcnt
Pcnt
Volume
Pcnt
Occurrence
Outflow
Storage Unit 1000 ft3
Full
Loss
1000 ft3
Full
days hr:min
CFS
------------------------------------------------
3 0.848
11
0
---------------------------------
7.450
100
0 00:35
31.78
Outfall Loading Summary
-----------------------------------------------------------
FlowAvg. MaxTotal
Freq. Flow Flow Volume
Outfall Node Pont. CFS CFS 10^6 gal
5 97.64 9.96 73.78 1.573
--- -------------- --------------
System 97.64 9.96 .73.78 1.573
Link Flow Summary
Link
5
9
10
11
12
13
14
15
16
2
Type
CONDUIT
CONDUIT
CONDUIT
CONDUIT
CONDUIT
CONDUIT
CONDUIT
CONDUIT
CONDUIT
DUMMY
Conduit Surcharge Summary
«*****************##+++++
Maximum
Time
of Max
IFlowl
Occurrence
CFS
days
hr:min
--------------------
123.61
0
00:40
26.27
0
00:40
24.05
0
00:23
18.05
0
00:33
42.05
0
00:33
42.03
0
00:34
42.02
0
00:34
73.78
0
0 0 : 4 6
73.78
0
00:40
31.78
0
0 0 : 4 7
------------------------
Maximum
Max/
Max/
Velocl
Full
Full
ft/sec
------------------------
Flow
Depth
>50 00
0.00
0.04
>50.00
0.00
0.02
8.25
0.94
0.77
6.87
0.96
0.78
10.53
0.59
0.55
8.39
0.79
0.67
9.91
0.64
0.58
15.64
0.34
0.40
12.63
0.45
0.47
SWMM 5 Page 3
--------- Hours Full --------
Conduit Both Ends Upstream Dnstream
----------------------------------------------------
10 0.01 ,0.01 0.01
Analysis begun on: Thu Feb 07 15:29:24 2013
Analysis ended on: Thu Feb 07 15:29:24 2013
Total elapsed time: < 1 sec
Hours Hours
Above Full Capacity
Normal Flow Limited
1.18 0.01
SWMM 5 Page 4
Water Quality Appendix
Pond
ATC
a: 2.1.13
IONS
:QUIRED STORAGE & OUTLET WORKS:
BASIN AREA = 0.190 <-- INPUT from impervious calcs
BASIN IMPERVIOUSNESS PERCENT = 90.00 <-- INPUT from impervious calcs
BASIN IMPERVIOUSNESS RATIO = 0.9000 <--CALCULATED
WQCV (watershed inches) = 0.401 <-- CALCULATED from Figure EDB-2
WQCV (ac-ft) = 0.006 <-- CALCULATED from UDFCD DCM V.3 Section 6.5
WQ Depth (ft) = 1.800 <-- INPUT from stage -storage table
AREA REQUIRED PER ROW, a (in2) = 0.027 <-- CALCULATED from Figure ED13-3
CIRCULAR PERFORATION SIZING:
dia (in) = 1/4
<-- INPUT from Figure 5
n = 5.000
<-- INPUT from Figure 5
t (in) = 0.500
<-- INPUT from Figure 5
number of rows = 1.000
<-- CALCULATED from WQ Depth and row spacing
DRAWING FILENAME: D:\ProJects\207-008\Dwg\Omg\207-008—DRNG.dwg LAYOUT NAME: C4.00 DATE: Mor.28, 2013 — 6:36om CAD OPERATOR: cody
UST OF %REFS [207-007—XEUTIL] [207-007�Exst] [207-007. Site] [207-007�Topo] [207—OO8-,xExst Off —Site] [207-008—xPgrod] [207-008�Site] [207-008�Topo Off —Site] [Newnan—x8order]
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INV. SE. 4961'11((162'RCPADS)
/
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INV. NE � 4956.75 (W RCP)
IHV. 9W - e95R61 (36 RCP)
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GRAPHIC SCALE
e NORTH
30 0 50 60 90 Feel
„ IN FEET )
1 eN - 30 ft.
LEGEND
PROPERTY BOUNDARY
PROPOSED BASIN UNES
— — — — — —
EXISTING STOMM SEWER LINE W/ MH
TeeNESSEE@
PROPOSED UNDERDRAIN
UO
EXISTING INLET GRATE
® O
PROPOSED CONTOUR
93—
EXISTING CONTOUR
- - - -5013- - - -
PROPOSED VERDCAL
CURB k GUTTER
PROPOSED OVERLAND ROW OIRFCTMI
w�
PROPOSED BASIN ONNEAiICN
B1
PROPOSED MINOR RUNOFF COFFIdENT
PROPOSED O MAJOR RUNOFF CFFICIENT
PROPOSED BASIN ACREAGE
PROPOSED DESIGN PUNT
R
NOTES:
THE SIZE, TYPE AND LOCATION CF ALL KNOWN UNDERGROUND
UTILITIES ARE APPROXIMATE 'MIEN SHOWN ON THESE ORAVANGS.
IT SHALL BE THE RESPONSIBILITY OF THE CONTRACTOR TO
VERIFY THE EXISTENCE OF ALL UNDERGROUND UTILITIES IN THE
AREA OF THE WORN. BEFORE COMMENCING NEW CONSTRUCTION
THE CONTRACTOR SHALL BE RESPONSIBLE FOR LOCATING ALL
UNDERGROUND UTIUTIES AND SHALL BE RESPONSIBLE FOR FOR
ALL UNKNOWN UNDERGROUND UTILITIES
BENCHMARK
1-00: LOCATED ON A CATCH BASIN AT THE SOUTHEAST CORNER OF
THE INTERSECTION OF MNE DRIVE AND COLLEGE AVENUE.
ELEVATION - 4965,57 (NGYO 29 UNADJ STED)
5-00, LOCATED ON THE TOP OF CURB AT THE SIGNAL POE BASE
AT ME NORTHWEST CORNER OF UNOEN STREET AND JEFFERSON
STREET.
ELEVATION . 4974 B] (NOW 29 UNADJUSTED)
FOR DRAINAGE REVIEW ONLY
NOT FOR CONSTRUCTION
cAu uTnNrr NO O R ADON CFNTEB OF
caoRADo
AKn.
Cell b61orsyou 61g.
e,Mr.c aW N•9 rass Nunes.
City of Fort Collins, Colorado
UTILITY PLAN APPROVAL
APPROVED:
Lily ng nccr
CHECKED BY:
r
CHECKED BY:� —Tate—
CHECKED BY:
Perks k ecreetum �e
CHECKED BY: -----TFaIlr)`Tn—eer --Z-a—
CHECKED BY:
Environmental Planner --Zar�--
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STORM Mill-
1. HIM .4967.e5
.11 W V. N.4962.e0 (36- RCP)
I WV. S.4962.70 (56- PCP)
.� WV. SW. 4963.85 (IS ' RCP)
�PROPOSFD WATER
ORIFICE KATEW/
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(9 NORTH
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CN . SO 11
LEGEND
PROPERTY BOUNDARY
EXISTING STORM SEWER LINE W/ MH
EXISTING INLET DRAT:
13
PROPOSED CONTOUR
9S
EXISTING CONTOUR
----5015----
PROPOSED INFLOW CURB k GUTTER
PROPOSED RIBBON CURB
APPROXIMATE UNITS OF DISTURBANCE
LCO—
WATTLE INLET PROTECTION
(p
WATTLE
O
rrsarsa
WATTLE SEDIMENI TRAP
$T
CONCRETE WASHOUT AREA
O
VEHICLE IRACIONO PAID
VT
PLANTED RIPRAP
RR.
NOTES
I. THE SIZE, TYPE AM LOCATION OF ALL KNOWN UNDERGROUND UTWTCS
ARE APPROXIMATE MEN SHOWN ON THESE DRAWNCS, IT SHALL BE ONE
RESPCN9BILI7Y BE ME CONTRACTOR TO WRIFY THE EXISTENCE BE ALL
UNDERGROUND UTILITIES IN ME AREA OF ME WORK. BEFORE
COMMENCING NEW CONSTRUCTION, THE CONTRACTOR SHALL BE
RESPONSIBLE FOR LOCATING ALL UNDERGROUND UTWTES AND SHALL BE
RESPONSIBLE FOR ALL UNKNOWN UNDERGROUND UTILITIES,
2. EROSION CONTROL PRAC110E5. SITE PROTECTION, AND RELSGETATION
METHODS SHALL FOLLOW CITY REGULATIONS
3, IT SHOULD BE NOTED THAT ANY EROSION CONTROL PLAN SERVES ONLY
AS A GODELINE TO THE CONTRACTOR STAGING AND/M PHASING OF
BEST MANAGEMENT PRACTICES (BVP.)IS EXPECTED. ADDITIONAL
AND/OR DIFFERENT BMI FROM M04 ORIGINALLY DEPICTED MAY BE
NECESSARY DURING CONSTRUCTION DUE TO CHANGING SITE CONDITIONS
OR AS REQUIRED BY LCCAL AUTHORITIES,
♦. THIS EROSION CONTROL PLAN IS SCHEMATIC IN NATURE. AS SUCH,
GRAPHICAL SYMBOLS MAY NOT BE TO SCALE. NOW ARE THEY
NECESSARILY SHOWN IN THEIR EXACT LOCATION.
5. THE CONTRACTOR SHALL BE RESPONSIBLE FOR ALL PERMNTNG (CITY.
STATE DISCHARGE PERMIT, ETC.) AND COMPLIANCE WIN GOVERNING
AUTHORITIES. IT SHALL BE THE RESPONSIBILITY OF THE CONTRACTOR
(OR PERMIT HOLDER) TO ENSURE EROSION CONTROL MEASURES ARE
PROPERLY MAINTAINED AND FOLLOWED,
6. CONTRACTOR SHALL IMPLEMENT THE APPROPRIATE EROSION CONTROL
MEASURES ACCORDING ME THE CONSTRUCTION SEQUENCING AND LEAL
OF SITE STABtt1ZATCN.
). CONTRACTOR SHALL IMPLEMENT APPROPRIATE INLET PROTECTION FOR ALL
STERN DRAINS UNTIL SITE IS FULLY STABIUZED, INLET PROTECTION SHALL
BE ADAPTED, AS NECESSARY. TO THE SURROUNDING SURFACE TYPE AND
COMMON (i.e.. STATUE-ORIVEN WATTLES FOR BARE SEL SAND BAGS OR
GRAVEL SOCKS FOR PAVEMENT. ETC.)
B. CONTRACTOR IS RESPONSIBLE FOR STABILIZING ALL SLOPES
PARTICULARLY THOSE STEEPEN THAN 6:1, CRIMP MULCHING. HYDRO
MULCHING, EROSION MATS. TEMPORARY IRRIGATION. AND ADOTCNAL
WATTLES OR SILT FENCING MAY BE NECESSARY TO ESTABLISH
VEGETATIVE COVER AND STABUZE THE SLOPE.
9. SCE LANDSCAPE PLANS FOR ADDITIONAL INFORMATION ON RANTING,
RMGETAMBN. HARDSCAPE AND OTHER PERMANENT SITE STABILIZATION
METHODS
10. SEE 'GRADING A EROSION CONTROL NOTES' ON SHEET C0.02 BETHE
MINOR AMENDMENT PLAN SET FOR THE NOIMMOF AMAN COMMUNITY
CENTER PREPARED BY NORTHERN ENENEERWG DATED FEBRUARY 26M.
2013 FOR ADDITIONAL WFCRMAMCN,
TABLE OF CONSTRUCTION
SEQUENCE AND BMP APPLICATION
Pro Am Nomwde ANlan CommOniN Center
PRXIEW. Krxue IINIeI
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