HomeMy WebLinkAboutDrainage Reports - 03/23/2006 (2)Sinai Approved Report
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90% DESIGN DRAINAGE STATEMENT
FOR
LEMAY AVENUE WIDENING (2006)
Prepared for:
CITY OF FORT COLLINS
281 North College Avenue
Fort Collins, Colorado
Prepared by:
North Star Design
700 Automation Drive, Unit I
Windsor, Colorado 80550
(970)686-6939
January 30, 2006
NSD Job Number 203-24
� I
North Star
,Al`. design, inc.
January 30, 2006
' Mr. Basil Hamdan
City of Fort Collins
Stormwater Utility
' 700 Wood Street
Fort Collins, Colorado 80522-0580
RE: 90% Design Drainage Letter for Lemay Avenue Widening (2006)
Dear Basil,
' Please accept this letter as the 90% Drainage Design Statement for the above project.
Attached are all of the drainage calculations for the project as well as your redlines from
' the 50% review. Attached to this letter are four appendices.-
* Appendix A — Vicinity Map
' • Appendix B — Project Hydrology
• Appendix C — Inlet and Street Capacity Hydraulics
• Appendix D — Drainage Plan
This project is going to widen Lemay Avenue between Carpenter Road and Nassau Way
(1/2 mile). Curb will be added to the east side of the street; the west side will remain
unchanged.
Lemay Avenue between Carpenter Road and Trilby Road has one major sump (500'
' north of Carpenter Road), and one major ridge (1,900' north of Carpenter Road). There
is an inlet at the sump and also inlets at the intersection of Lemay Avenue and Nassau
Way. A new intersection (Mountain Home Drive) will be installed at the ridge. All
' water from this stretch of Lemay Avenue drains to Stanton Creek. Lemay Avenue is
bounded on the west by Provincetowne PUD and on the east by Emerson Acres, the
future Lemay Estates, and Stanton Creek Subdivision.
The existing road (constructed in 1985), Provincetowne Filing 1 and 2, Emerson Acres,
' and Stanton Creek were all designed and built when Stanton Creek was a "free release"
basin (no detention was required). Because of this, there is presently no detention
provided for any of Lemay Avenue and there is no logical place to provide any detention
at this time (this project will just widen the existing street with no reasonable opportunity
to change the drainage scheme).
The project has been divided into six basins for analysis.. Basins 1, 2, and 3 have no
appreciable change from existing conditions. Basins 4, 5, and 6 include the areas that
will be widened with the project.
700 Automation Drive, Unit I Windsor, Colorado 80550
970-686-6939 Phone 0 970-686-1 188 Fax
' Basin 1 — includes the west half of Lemay north of the ridge (Mountain Home Drive).
This basin does not change substantially from existing conditions. It drains to the north
to the inlets and storm sewer at Nassau Way.
Basin 2 — includes the west half of Lemay south of the right. This basin drains south to
' the existing 10' Type R inlet at the sump. Again, the drainage does not change
substantially, there is drainage from the west the flows into the street and has been
' accounted for in the calculations. The street capacity has been checked in this area — the
center lane is free from water during the 100-year storm and the existing inlet can take
the 100-year storm without topping the new crown of the street.
' Basin 3 — includes the west half of Lemay south of the sump. Carpenter Road will be
widened and slightly more flow will result, to the sump. As shown for Basin 2, street
' capacity and the existing inlet capacity are acceptable.
Basin 4 — includes the west half of Lemay north of Mountain Home Drive. This portion
of Lemay will drain north to the inlets at Nassau Way.
Basin 5 — includes the east half of Lemay between Mountain Home Drive and the sump.
' The south portion of this site (adjacent to Emerson Acres) will only have curb and gutter
installed at this time. The addition of sidewalk will likely wait for the redevelopment of
the existing lots. A 10' Type R inlet is proposed at the sump and it has adequate capacity
for the improvements. The existing pipes in the sump will be extended to the new toe of
slope and the existing riprap will be moved down the existing channel. There are no off
site flows to the street in this area as the land to the east all drains directly to Stanton
' Creek. This section of street easily meets the minor street capacity and the calculations
show that it will also easily meet the major storm street capacity once sidewalk is
installed on the east side of the street.
Basin 6 — includes the east half of Lemay south of the sump. This is a very small area
that drains in the new curb and gutter to the north and into the new inlet at the sump.
' I appreciate your time in reviewing this information and the 90% plans. It is our intent to
review the Erosion Control Plan with Bob Zakely directly and not provide erosion control
' design calculations in the final report (similar to what was done on the Timberline
Project). Please call me if you have any questions or need any additional information.
' Sincerely,
North Star Design, Inc.
i---- - P"'J(
Michael Oberlander, P.E., L.S.I.
Appendix A — Vicinity Map
PROJECT
LOCATION
VICINITY MAP
SCALE: 1" = 1.000'
' Appendix B — Project Hydrology
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Appendix C — Inlet and Street Hydraulics
IF ..... ... . .. ....... - . ..... .INLET OR SAO. LOCATION.
....... .... ..
.... . . ... .
Project .. ........ �....vLEMAY.n0v
.... ... . . .
.. ......... . EXISTING . .. ....... .... ..
Inlet ID FXIS.-MG IV. INLET Witst...
Waning �
'I , Lo (C)I
H-Curb H-Vert c,
LolGl
Design Information (input)
Type of Inlet
Type = cbOT:Type R Curb Opening,
Local Depression (in addition to gutter depression'a'from'Q-Allow)
aw,6
: -3.00 inches
Number of Unit Inlets (Grate or Curb Opening)
No
2
Grate Information
Length of a Unit Grate
L, (G)
:N/A: feet
Width of a Unit Grate
W
N/A feet
Area Opening R ado for a Grate (typical values 0. 15-0.90)
Ag.
N/A'
Clogging Factor for a Single Grate (typical value 0.50)
Cf (G)
N/A'
Grate Weir Coefficient (typical value 3.00)
C„ (G)
NIA
Grate Orifice Coefficient (typical value 0.67)
C, (G)
WA
Curb Opening Information
Length of a Unit Curb Opening
L, (C)
.5.00 feet
Height of Vertical Curb Opening in Inches
H.d = 1
6:00 inches.
Height of Curb Orifice Throat in Inches
H,.j -
:::5:96 inches
Angle of Throat (see USDCM Figure ST-5)
Theta
63-4 degrees
Side Width for Depression Pan (typically the gutter width of 2 feet)
W,
400 feet
Clogging Factor for a Single Curb Opening (typical value 0.10)
Cf (C)
0 10
Curb Opening Weir Coefficient (typical value 2.30-3.00)
(C)
.2 30.
Curb Opening Orifice Coefficient (typical value 0.67)
C, (C)
67
Resulting Gutter Flow Depth for Grate Inlet Capacity in a Sump
Clogging Coefficient for Multiple Units
Coef
Clogging Factor for Multiple Units
Clog
As a Weir
Flow Depth at Local Depression without Clogging (0 cfs grate, 21.5 cfs curb)
cl�
WA. inches
Flow Depth at Local Depression with Clogging (0 cfs grate, 21.5 cfs curb)
d.
NIA inches
s an Orifice
Flow Depth at Local Depression without Clogging (0 cfs grate, 21.5 cfs curb)
cl
inches
Flow Depth at Local Depression with Clogging (0 cfs grate, 21.5 cfs curb)
cl„
WA inches
Resulting Gutter Flow Depth Outside of Local Depression
inches
Resulting Gutter Flow Depth for Curb Opening Inlet Capacity in a Sump
Clogging Coefficient for Multiple Units
Coef =
12 56
Clogging Factor for Multiple Units
Clog =
Curb as a Weir, Grate as an Orifice
Flow Depth at Local Depression without Clogging (0 cfs grate, 21.5 cfs curb)
d
9i4i inches
Flow Depth at Local Depression with Clogging (0 cfs grate, 21.5 cfs curb)
cl.�
9 6 inches
'Curb as an Orifice, Grate as an Orifice
Flow Depth at Local Depression without Clogging (0 cfs grate, 21 .5 cfs curb),
cl� �:i: .i�
11.4; inches
Flow Depth at Local Depression with Clogging (0 cfs grate, 21.5 cfs curb)
cl
1.15 inches.
Resulting Gutter Flow Depth Outside of Local Depression
n ches
Resultant Street Condition
Total Inlet Length -
L
feet
Total Inlet Interception Capacity (Design Discharge from Q-Peak)
0.
:21;5: cfs
Resultant Gutter Flow Depth (based on sheet Q-Allow geometry)
d
6.5 inches
Resultant Street Flow Spread (based on sheet Q-Allow geometry)
T
feet
Resultant Flow Depth at Maximum Allowable Spread
dSPREAD
inches
Waming 5: Outter flow depth isgrtattn than the 6 inches allowed for the MINOR STORM (set shett'2-Allov;';
INLETS.xis, Inlet In Sump 01130/2006, 7:24 AM
INLET IN A: SUMPOR SAG LOCATIONsq
Project
Inlet ID
,F—Lo (C) I
�ASi+�S 5-�-4
Design Information llngutl
Type of Inlet
Type CDOT Type R Curb Opening
Local Depression (in addition to gutter depression'a' from'D-AIIoW)
a„ a
3.00inches
Number of Unit Inlets (Grate or Curb Opening)
No ............
........i
Grate Information
...........................
Length of a Unit Grate
L, (G)
N/A` feet
Width of a Unit Grate
W
N/A: feet
ea Opening Ratio fora Grate (typical values 0.15-0,90)
haeo
.....
.... WA-:
Clogging Factor for a Single Grate (typical value 0.50) -
C, (G)
WA.
Grate Weir Coefficient (typical value 3.00)
G. (G)
NIA:
Grate Orifice Coefficient (typical value 0.67)
C, (G)
:N/A
Curb Opening Information
Length of a Unit Curb Opening
L, (C)
5 00. feet
Height of Vertical Curb Opening in Inches
H,,,,
6 00 inches
Height of Curb Orifice Throat in Inches
He,- a
5:96. inches
Angle of Throat (see USDCM Figure ST-5)
Theta
63;A. degrees
Side Width for Depression Pan (typically the gutter width of 2 feet)
W,
2.00' feet
Clogging Factor for a Single Curb Opening (typical value 0.10)
Cr (C)
0,10'.
Curb Opening Weir Coefficient (typical value 2.30-3.00)
C. (C)
2i30!
Curb Opening Orifice Coefficient (typical value 0.67
Co (C)
0,67
Resulting Gutter Flow Depth for Grate Inlet Capacity in a Sump
Clogging Coefficient for Multiple Units
Coef
SAY:
Clogging Factor for Multiple Units
..........................
Clog
NPA
As a Weir
...........................
Flow Depth at Local Depression without Clogging (0 cfs grate, 15.1 cfs curb)
...........................
...........................
inches
Flow Depth at Local Depression with Clogging (0 cfs grate, 15.1 cfs curb)
d,„, ,,....:.�
:::Nip! inches
As an Orifice
Flow Depth at Local Depression without Clogging (0 cfs grate, 15.1 cfs curb)
d
WA': inches
Flow Depth at Local Depression with Clogging (0 cfs grate, 15.1 cfs curb)
d„N..fA:
inches
Resulting Gutter Flow Depth Outside of Local Depression..::.NIAi
Inches
Resultina Gutter Flow Depth for Curb Opening Inlet Capacity in a Sum
.....................
...........................
.
Clogging Coefficient for Multiple Units
...........................
...........................
Coef =:#i35i
Clogging Factor for Multiple Units
Clog =0.06I
Curb as a Weir, Grate as an Orifice
...........................
...........................
Flow Depth at Local Depression without Clogging (0 cfs grate, 15.1 cfs curb)
...........................
...........................
d„,
inches
Flow Depth at Local Depression with Clogging (0 cfs grate, 15.1 cis curb)
ci„
k!6! inches
Curb as an Orifice, Grate as an Orifice
...........................
...........................
Flow Depth at Local Depression without Clogging (0 cfs grate, 15.1 cfs curb)
...........................
..........................
d
��: '6:5' inches
Flow Depth at Local Depression with Clogging (0 cis grate, 15.1 cfs curb)
d„
.:;:.70 inches
Resulting Gutter Flow Depth Outside of Local Depression
d,z,,,,
4:6 inches
Resultant Street Conditions
Total Inlet Length
L
10.0� feet
Total Inlet Interception Capacity (Design Discharge from O-Peak)
Q.
151> cfs
Resultant Gutter Flow Depth (based on sheet Q-Allow geometry)
d— .............:......:4:8:
Inches
Resultant Street Flow Spread (based on sheet Q-Allow geometry)
T =;.,,;,;,,,.�!:_;,;,,.;
1?;H: feet
Resultant Flow Depth at Maximum Allowable Spread
dzree,,e =
0 Inches
INLETS.xis, Inlet In Sump
OV30/2006, 7:24 AM
LOCATION: LEMAY 2006
ITEM: STREET CAPACITY
COMPUTATIONS BY: MPO
SUBMITTED BY: NORTH STAR DESIGN INC.
10-year design storm
Design in accordance to "Storm Drainage Design Criteria and Construction Standards"
City of Fort Collins, May 1984.
Street with 74' Roadway, vertical curb and gutter
no curb topping, flow may spread to crown of street
calculate for channel slopes from 0.4% to 7%
Theoretical Capacity: use revised Mannings eq.
Allowable Gutter Flow:
Q=0.56-Z/n-S12'y&'
Qall=F'Q
where
Q =
theoretical gutter capacity (cfs)
F = reduction factor (Fig. 4-2)
Z =
reciprocal of cross slope (ft/ft)
Qall = allowable gutter capacity (cfs)
n =
roughness coeff.
S =
channel slope (ft/ft)
Q = Qa - Qb + Qc
y =
depth of flow at face of gutter (ft)
sec. A
FL
Z
n
ya
S
Q.
12
0.013
0.5
0.40%
5.15
12
0.013
0.5
0.50%
5.76
B
12
0.013
0.5
0.60%
6.31
12
0.013
0.5
0.80%
7.28
12
0.013
0.5
1.00%
8.14
12
0.013
0.5
1.50%
9.97
12
0.013
0.5
2.00%
11.51
12
0.013
0.5
3.00%
14.10
12
0.013
0.5
4.00%
16.28
12
0.013
0.5
5.00%
18.20
12
0.013
0.5
6.00%
19.94
12
0.013
0.5
7.00%
21.54
Spr. R
Z
n
yb
S
Qb
12
0.013
0.33
0.40%
1.70
12
0.013
0.33
0.50%
1.90
12
0.013
0.33
0.60%
2.08
12
0.013
0.33
0.80%
2.40
12
0.013
0.33
1.00%
2.69
12
0.013
0.33
1.50%
3.29
12
0.013
0.33
2.00%
3.80
12
0.013
0.33
3.00%
4.66
12
0.013
0.33
4.00%
5.38
12
0.013
0.33
5.00%
6.01
12
0.013
0.33
6.00%
6.59
12
0.013
0.33
7.00%
7.11
SPr r
q
�-- yb=y°= 0.33ft
ya= 0.5 ft
Z. =
24"/2" =
12
Zb =
2472" =
12
Z° =
1 /0.02 =
50
Both sides
n = n= - nh + nr of CIrPPI
Z
n
Y.
S
Q°
Q
F
Qan
Clan
50
0.016
0.33
0.40%
5.76
9.20
0.50
4.60
9.20
50
0.016
0.33
0.50%
6.44
10.29
0.65
6.69
13.38
50
0.016
0.33
0.60%
7.05
11.27
0.80
9.02
18.04
50
0.016
0.33
0.80%
8.14
13.02
0.80
10.41
20.83
50
0.016
0.33
1.00%
9.10
14.55
0.80
11.64
23.29
50
0.016
0.33
1.50%
11.15
17.83
0.80
14.26
28.52
50
0.016
0.33
200%
12.87
20.58
0.80
16.47
32.93
50
0.016
0.33
i l)0%
15.76
25.21
0.72
18.15
36.30
50
0.016
0.33
4.00%1
18.20
29.11
0.60
17.47
34.93
50
0.016
0.33
5.00%1
20.35
32.54
0.48
15.62
31.24
50
0.016
0.33
6.00%1
22.29
36.72
0.40
14.69
29.38
50
0.016
0.33
7.00%1
24.08
38.51
0.34
13.09
26.18
SlrtcaplAs 1 of 1
LOCATION: LEMAY 2006
ITEM: STREET CAPACITY
COMPUTATIONS BY: MPO
SUBMITTED BY: NORTH STAR DESIGN INC.
100-year design storm
Design in accordance to "Storm Drainage Design Criteria and Construction Standards"
City of Fort Collins, May 1984.
Street with 74' Roadway, vertical curb and gutter - collector street
depth of water over crown not to exceed 6", buildings shall not be inundated at the ground line
calculate for channel slopes from 0.4% to 7%
Theoretical Capacity: use Mannings eq. Allowable Gutter Flow:
Q=1.486/n-R' -S1n'A Qall =F'Q
where _Q = theoretical gutter capacity (cfs) F = reduction factor (Fig. 4-2)
n = roughness_ coeff. Qall = allowable gutter capacity (cfs)
R= A/P
A = cross sectional area (ft) Q = Qa + Qb
P = wetted perimeter (ft)
S = channel slope
sec. A sec. B
A = 11.20 A = 2.25
P = 33.80 P = 15.30
R= 0.33 R= 0.15
n = 0.016 n = 0.035 Both sides
of ctroot
S
Qa
S
Qb
Qtot
F
Qall
Qall
0.400/6
31.59
0.40%
1.69
33.28
0.50
16.64
33.28
0.50%
35.32
0.50%
1.89
37.20
0.65
24.18
48.36
0.60%
38.69
0.60%
2.07
40.75
0.80
32.60
65.21
0.80%
44.67
0.80%
2.39
47.06
0.80
37.65
75.29
1.00%
49.94
1.000%
2.67
52.61
0.80
42.09
84.18
1.50%
61.17
1.50%
3.27
64.44
0.80
51.55
103.10
2.00%
70.63
2.00%
3.77
74.41
0.80
59.53
119.05
3.00%
86.51
3.00%
4.62
91.13
0.72
65.61
131.23
4.00%
99.89
4.00%
5.34
105.23
0.60
63.14
126.27
5.00%
111.68
5.00%
5.97
117.65
0.48
56.47
112.94
6.00%
122.34
6.00%
6.54
128.88
0.40
51.55
103.10
7.00%
132.14
7.00%
7.06
139.20
0.34
1 47.331
94.66
FL CL
all
0.63'
0.17'
Area A = (0.15')(23') + (2"/12)-(2')-(1/2) + (5.52"/12)'(2') + (5.52"/12)'(23')'(l/2) = 9.83 sq. ft.
Area B = (14')`(3.36/12)'(1/2) = 1.96 sq. ft.
' Strtcapl.xls 1 of 1
LOCATION: LEMAY 2006
ITEM: STREET CAPACITY
COMPUTATIONS BY: MPO
SUBMITTED BY: NORTH STAR DESIGN INC.
Note: Design flows and street capacities are given for one side of the street unless otherwise indicated
Des.
Street Name
Roadway
Slope
10 yr
Design flow
meets
100 yr
Design flow
meets
Width-
(°/,)
Capacity
Q(10)
criteria?
Capacity
Q(100)
criteria?
Point
(ft)
(cfs)
(cfs)
(cfs)
(cfs)
2
WEST SIDE LEMAY
74
0.5
6.7
3.0
yes
24.2
13.1
yes
5
EAST SIDE LEMAY
74
0.5
6.7
2.7
yes
24.2
11.4
yes
1 of
Appendix D — Drainage Plan
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EXISTING PIPES
® 60 ]0 0 60 130
PROPOSED STORM PIPE
. PROPOSED INILET LOCATION SCALE: ,' = 60
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♦------- EXISTING Y CONTOUR CALL UTILITY COLORADON
PROPOSED s CGNTWR 1-800 922-1987
t H]s — PROPOSED V CONTOUR CALL 3 DAYS Al I t / Q BEFORE IOU
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— oEEIGNEO DY DRA APPROVED BY SOUTH EMAY AVENUE WIDENING (2006)lHLEI
— CITY OF FORT COLLINS, COLORADO MPO I MPOI
- _-- - lifirT.AI^� SCALe DATE - cNECBED DY: DNTC - 90% SUBMITTAL or
-- ENGINEERING DIVISION �> �°^ 1"=60' 1/19/06 _- DRAINAGE- PLAN _— I