HomeMy WebLinkAboutSTONERIDGE PUD, FOURTH FILING, PHASE II FINAL - 21 92K - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORT' Northern Engineering Services, Inc.
March 18, 1996
If
City of Fort Collins
Stormwater Utility
235 Mathews
' Fort Collins, Colorado 80522
■ RE: Stone Ridge P.U.D. Fourth Filing, Phase II
Fort Collins, Colorado
Project Number: 9613.00
Dear Staff:
LNorthern Engineering is pleased to submit this Final Drainage Report for Stone
Ridge P.U.D. Fourth Filing, Phase II for your review.
This report was prepared in compliance with technical criteria set forth in the
' City of Fort Collins Storm Drainage Design Criteria and Construction Standards
manual.
1 If you should have any questions or comments as you review this report, please
feel free to contact me at your convenience.
rSincerely,
NORTHERN ENGINEERING SERVICES, INC.
George A. Schoc
Mary B. Wohnrade,
I
1 420 S. Howes, Suite 202 • Fort Collins, Colorado 80521 • (970) 221-4158 • Fax (970) 221-4159
DEVELOPED HYDROLOGY
Stone Creek P.U.D Fourth Filing, Phase II, Fort Collins, CO.
File Number: DSNPT34.WQ1 15-Mar-96 Calc
DESIGN POINT 34: (Includes Basin 34)
TOTAL AREA = A (ac)=
4.100
RUNOFF COEFFICIENTS:
(From Table 3-3)
Impervoius Area/ Lot (ac)=
1.9400
C for Roofs =
0.95
Area of Streets and Walks(ac)=
1.1300
C for Concrete =
0.95
Area of Gravel Parking (ac)=
0.0000
C for Gravel =
0.50
Area of Lawn (ac)=
1.0300
C for Lawn =
0.25
COMPOSITE RUNOFF COEFFICIENT:
C = 0.95(1.94+1.13)+0.25(1.03) = 0.77
4.1
Cf = 1.00 (Frequency Adjustment Factor; Storm Return Period of 2- Years)
Cf = 1.25 (Frequency Adjustment Factor; Storm Return Period of 100- Years)
OVERLAND FLOW:
T2 = 1.87 (1.1 - CCf) SQRT(L) = 16.4
L (ft)= 150 CUBRT(S)
S (%) = 20.8-17.8 = 2.00 T100 = 1.87 (1.1 - CCf) SQRT(L) = 15.5
150 CUBRT(S)
C = 0.20
GUTTER FLOW: (To Sidewalk Culvert 34
L (ft)= 336 Tt =
S(%)= 17.3-15.3= 0.60
336
V(fps) = 1.90
2-YEAR TIME OF CONCENTRATION; Tc2 =
100-YEAR TIME OF CONCENTRATION; Tc100 =
RAINFALL INTENSITY:
FROM FIGURE 3-1: i2(in/hr)= 1.88
19.3 min
18.4 min
i100(in/hr)= 5.35
Q2(cfs) = CCf x i2 x A = 6.0 4:� o/< (.St -r5 , i i )
Q100(cfs)= CCf xi100xA= 21.2 < 25.(e oi�- C=cffa 1:--k. /3
I
L = 2.9
60(V)
min
min
min
■
z
DEVELOPED HYDROLOGY
Stone Creek P.U.D Fourth Filing, Phase II, Fort Collins, CO.
File Number: DSNPT34a.WQ1 15-Mar-96 Cale
DESIGN POINT 34a: (Includes Basin 34a)
TOTAL AREA = A (ac)= 2.180
RUNOFF COEFFICIENTS:
(From Table 3-3)
Impervious Area/ Lot(ac)=
1.1200
C for Roofs =
0.95
Area of Streets and Walks(ac)=
0.5900
C for Concrete =
0.95
Area of Gravel Parking (ac)=
0.0000
C for Gravel =
0.50
Area of Lawn (ac)=
0.4700
C for Lawn =
0.25
COMPOSITE RUNOFF COEFFICIENT:
C = 0.95(1.12+.59)+0.25(.47) = 0.80
2.18
Cf = 1.00 (Frequency Adjustment Factor; Storm Return Period of 2- Years)
Cf = 1.25 (Frequency Adjustment Factor; Storm Return Period of 100- Years)
OVERLAND FLOW:
T2 = 1.87 (1.1 - CCf) SQRT(L) = 16.4
L (ft)= 150 CUBRT(S)
S (%) = 20.8-17.8 = 2.00 T100 = 1.87 (1.1 - CCf) SQRT(L) = 15.5
150 CUBRT(S)
C = 0.20
GUTTER FLOW: (To Sidewalk Culvert 34
L (ft)= 336 Tt =
S(a/o)= 17.3-15.3= 0.60
336
V(fps) = 1.90
2-YEAR TIME OF CONCENTRATION; Tc2 =
100-YEAR TIME OF CONCENTRATION; Tc100 =
RAINFALL INTENSITY:
FROM FIGURE 3-1: i2(in/hr)= 1.88
Q2(cfs) = CCf x i2 x A = 3.3
Q100(cfs) = CCf x i100 x A = 11.6
I
19.3 min
18.4 min
i100(in/hr)= 5.35
L = 2.9
60(V)
min
min
min
3/
DEVELOPED HYDROLOGY
Stone Creek P.U.D Fourth Filing, Phase II, Fort Collins, CO.
File Number: DSNPT34a.WQ1 15-Mar-96 Calc
DESIGN POINT 34b: (Includes Basin 34b)
TOTAL AREA = A (ac)= 1.920
RUNOFF COEFFICIENTS:
(From Table 3-3)
Impervious Area/Lot (ac)=
0.8700
C for Roofs =
0.95
Area of Streets and Walks(ac)=
0.5500
C for Concrete =
0.95
Area of Gravel Parking (ac)=
0.0000
C for Gravel =
0.50
Area of Lawn (ac)=
0.5000
C for Lawn =
0.25
COMPOSITE RUNOFF COEFFICIENT:
OVERLAND FLOW:
C = 0.95(.87+.55)+0.25(.50) = 0.77
1.92
Cf = 1.00 (Frequency Adjustment Factor; Storm Return Period of 2- Years)
Cf = 1.25 (Frequency Adjustment Factor; Storm Return Period of 100- Years)
-12 = 1.87 (1.1 - CCf) SQRT(L) = 10.0 min
L (ft)= 57.5 CUBRT(S)
S (%) = 18.2-17.0 = 2.09 T100 = 1.87 (1.1 - CCf) SQRT(L) = 9.4 min
57.5 CUBRT(S)
C = 0.20
GUTTER FLOW: (To Sidewalk Culvert 34
L (ft)=
318.5
S (%) =
16.65-15.3 =
318.5
V(fps) =
1.45
0.42
Tt = L = 3.7 min
2-YEAR TIME OF CONCENTRATION; Tc2 = 13.6 min
100-YEAR TIME OF CONCENTRATION; TC100 = 13.1 min
RAINFALL INTENSITY:
FROM FIGURE 3-1: i2(in/hr)= 2.20 i100(in/hr)= 6.35
Q2(cfs) = CCf x i2 x A = 3.2
Q100(cfs) = CCf x i100 x A = 11.7
I
60(V)
4/
DEVELOPED HYDROLOGY
Stone Creek P.U.D Fourth Filing, Phase II, Fort Collins, CO.
File Number: DSNPT35.WQ1
DESIGN POINT 35: (Includes Basin 34 and
TOTAL AREA BASIN 34 = 4.100
TOTAL AREA BASIN 35 = 1.950
TOTAL AREA BASIN 34 AND 35= 6.050
RUNOFF COEFFICIENTS:
C FOR BASIN 34 = 0.7700
C FOR BASIN 35 = 0.3300 (See Pg. 11, Appendix)
COMPOSITE RUNOFF COEFFICIENT:
15-Mar-96 Calc
C = 0.77(4.1)+0.33(1.95) = 0.63
6.05
Cf = 1.00 (Frequency Adjustment Factor; Storm Return Period of 2- Years)
Cf = 1.25 (Frequency Adjustment Factor; Storm Return Period of 100- Years)
BASIN 34 TIME OF CONCENTRATION:
2-YEAR TIME OF CONCENTRATION; Tc2= 19.3 min.
100 YEAR TIME OF CONCENTRATION; Tc100= 18.4 min.
SWALE FLOW: (FROM DESIGN POINT 34 TO DESIGN POINT 35)
L (ft)= 575 Tt = L
S (%) = 15.3 - 11.2= 0.71 60(V)
575
V(fps) = 1.32
COMPOSITE TIME OF CONCENTRATION (BASIN 34 + BASIN 35)
2-YEAR TIME OF CONCENTRATION; Tc2 = 26.6 min
100-YEAR TIME OF CONCENTRATION; Tc100 = 25.7 min
RAINFALL INTENSITY:
FROM FIGURE 3-1: i2(in/hr)= 1.57 i100(in/hr)= 4.55
Q2(cfs) = CCf x i2 x A = 6.0
Q100(cfs) = CCf x i100 x A = 21.6
I
= 7.3 min
1
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■1 -
Stoneridge PUD, Fourth Filing TPM
Kaplan Co. 4-28-94 rev'd 2-28-95
This sheet calculates the composite "C" values for the Rational Method.
Design
Area
Imperviou
"C"
Perviou
"C"
A,total A,imp
ac. ac.
Percent
Im erv.
Percent
Perviou
Comp.
"C"
31
0.95
6.2
1.1C81
0.736
66.4
33.6
0.70
32
0.95
0.2
1.243
0.4
32.2
67.8
0.44
33
0.95
0.2
2.563
0.835
32.6
67.4
0.44
34
0.95
0.2
4.099
2.42
59.0
41.Oj
0.64
35
0.95
0.2
1.945
0.334
17.2
82.8
0.33
36
0.95
0.2
1.340
0.27
20.1
79.9
0.35
37
0.95
0.2
4.750
2,19
46.1
53.9
0.55
38
0.95
.0.21
1.7151
0.101
5.9
94.1
0.24
39
0.95
0.2
1.379
i.0.179
13.0
87.0
0.30
40
0.95
0.25
6.109i 2.539
41.6
58.41
0.54
41
0.95
0.25
0.9901. 0.155
15.7
84.3
0.36
42
0.95
0.21
C,.350 0.186
53.1
46.9
0.60
431
0.95
0.21
1.193
0.9551
80.1
19.9
0.80
441
0.95
0.2
0.900
0.101.1
11.2
88.8
0.28
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UNLINED CHANNEL DESIGN CRITERIA
' REFERENCE:
THE CITY OF FORT COLLINS "STORM DRAINAGE DESIGN CRITERIA
AND CONSTRUCTION STANDARDS", MAY, 1984.
SECTION 7.2, UNLINED CHANNELS
r1
)
MAXIMUM SIDE SLOPES = 4: 1
2)
MAXIMUM DEPTH OF FLOW IN CHANNEL = 4.0'
3)
SUBCRITICAL FLOW ONLY
4)
MINIMUM FREEBOAP.D = ADDITIONAL CAPACITY
FOR 1 /3 OF THE DESIGN FLOW.
5)
CHANNEL VELOCITY < 7.5 fps DURING
THE 1 00—YF STORM.
6)
CHANNEL VELOCITY > 2.0 fps DUPING
THE 2—YR STORM.
7)
MANNINGS "n" = 0.035 (See Tcble 2-4)
1
8)
MINIMUM SLOPE OF CHANNEL = 2.0%
(FOR `LOPES LESS THAN 2.07. A
A SUBDP.AII',I SHALL BE PROVIDED)
9)
MINIMUM PADIUS = 1 00' OR TWICE
THE TOPWIDTH OF THE DESIGN FLOW.
I
I
1 s/
Triangular Channel Analysis & Design
Open Channel - Uniform flow
'
Worksheet Name: STONE RIDGE
PUD
'
Comment: SWALE #34, Q2=6.0
Solve For Depth
CFS
Given Input Data:
'
Left Side Slope..
4.00:1 (H:V)
Right Side Slope.
4.00:1 (H:V)
Manning's n......
Channel Slope....
0.035
0.0060 ft/ft
Discharge........
6.00 cfs
'
Computed Results:
Depth.. •......
0.89 ft
Velocity.........
1.88 fps
Flow Area........
Flow Top Width...
3.19 sf
7.14 ft
Wetted Perimeter.
7.36 ft
'
Critical Depth...
Critical Slope...
0.67 ft
0.0267 ft/ft
Froude Number....
FULL
IM
I]
I
Open Channel Flow Module, Version 3.42 (c) 1991
Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708
I
1
Triangular Channel Analysis & Design
Open Channel - Uniform flow
Worksheet Name: STONE RIDGE P.U.D.]
Comment: Swale #34; Q100= 21.2 cfs
Solve For Depth
Given Input Data:
Left Side Slope..
Right Side Slope.
Manning's n......
Channel Slope....
Discharge........
Computed Results:
Depth............
Velocity.........
Flow Area........
Flow Top Width...
Wetted Perimeter.
Critical Depth...
Critical Slope...
Froude Number....
4.00:1
(H:V)
4.00:1
(H:V)
0.035
0.0060
ft/ft
21.20 cfs
1.43 ft
2.58 fps
8.21 sf
11.46 ft
11.82 ft
1.12 ft
0.0226 ft/ft
0.54 (flow is Subcritical)
Open Channel Flow Module, Version 3.42 (c) 1991
Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708
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Triangular Channel Analysis & Design
Open Channel - Uniform flow
Worksheet Name: STONE RIDGE PUD
Comment: SWALE #34, Q100 x 33% = 28.20 cfs
Solve For Depth
Given Input Data:
Left Side Slope.. 4.00:1 (H:V)
Right Side Slope. 4.00:1 (H:V)
Manning's n...... 0.035
Channel Slope.... 0.0060 ft/ft
Discharge........ 28.20 cfs
Computed Results:
Depth............
1.59
ft
Velocity.........
2.77
fps
Flow Area.... ...
10.17
sf
Flow Top Width...
12.76
ft
Wetted Perimeter.
13.15
ft
Critical Depth...
1.25
ft
Critical Slope...
0.0217 ft/ft
Froude Number....
FULL
1 Open Channel Flow Module, Version 3.42 (c) 1991
Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708
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' Final Drainage Report
for
Stone Ridge P.U.D. Fourth Filing, Phase II
1 1. INTRODUCTION
1.1 Objective
To provide a final drainage scheme for the proposed Stone Ridge planned unit
development Fourth Filing, Phase II based on master drainageway planning and
preliminary drainage concepts developed by others. Specific objectives as part of this
study are:
1. To adopt the drainage and grading concepts contained in the Final
Drainage and Erosion Control Study for Stone Ridge P U D
Fourth Filing, Phase I, (Reference 1),
2. To consider the drainage schemes of adjacent Stone Ridge P.U.D.
filings,
L3. To consider any possible adverse effects downstream of the
development due to developed stormwater,
1.2 Mapping and Surveying
1 Field survey information was provided by RBD, Inc. which included topographic
mapping with a contour interval of one (1) foot.
1.3 Site Reconnaissance
A site visit was conducted on Monday February 26, 1996 by the project
engineer. Based on the topographic mapping, existing drainage basins and land use
were confirmed as well as existing adjacent structures. The location of existing swales
and storm inlets were verified as well as their condition and flow direction.
II. SITE LOCATION AND DESCRIPTION
2.1 Site Location
The project is located in the South Half of the Southeast Quarter of Section 29,
Township 7 North, Range 68 West of the 6th Principal Meridian in Fort Collins,
' Colorado. The project is bounded by Horsetooth Road to the south and County Road
9 to the east. (See Vicinity Map). Adjacent developments include Stone Ridge P.U.D.
Fourth Filing, Phase I to the north and south.
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TABLE 4-1
INITIAL STORM - STREET RUNOFF ENCROACHMENT
Street Classmcatlon Maxkm Encroachment
LOCAL (Includes places, alleys No curb -overtopping. 'Flow may spread to
marginal access) crown of street.
COLLECTOR No curb -overtopping. 'Flow spread must
leave at least one lane width free of water,
MAJOR ARTERIAL No curb - overtopping. *Flow spread must
leave at least one-half of roadway
width free of water in each direction.
*. Where no curb overtopping exists, encroachment shall not extend over property lines.
TABLE 4-2
MAJOR STORM - STREET RUNOFF ENCROACHMENT
Street ClaaaMloason
Maxkr Enwcect m t
LOCAL (Includes places, alleys
Residential dwellings, public,
marginal access. & collector)
commercial and industrial buildings
shall not be inundated at the ground line
unless buildings are flood -proofed. The
depth of water over the crown shall not
exceed six (6) inches.
MAJOR ARTERIAL
Residential dwellings, public,
commercial and industrial buildings
shall not be inundated at the ground line
unless buildings are flood -proofed. Depth of
water at the street crown shall not exceed
six (6) inches to allow operation of emergency
vehicles. The depth of water over the
iu,tter flowline shall not exceed 18 inches.
In Borne cases, the 18 inch depth over the
gutter flowline is more restrictive than the
6 inch depth over the street crown. For
these conditions, the most restrivtive of
the two criteria shall govern.
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SLOPE OF CUTTER (7.)
REDUCTION FACTOR, F
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0.80
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SLOPE OF GUTTER (%)
Figure 4-2
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REDUCTION FACTOR FOR ALLOWABLE GUTTER CAPA.;ITY W
Apply reduction factor for applicable slope to the theoretical gutter capacity to obtain
allowable gutter capacity.
0
REFERENCE,
U.S. DEPARTMENT OF COMMERCE i
BUREAU OF PUBUC ROADS, 1965.
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Riprap Erosion Protection Calculations
Reference: Urban Storm Drainage Criteria Manual, Volume 2, Urban Drainage
and Flood Control District, March, 1969.
From Section 5.6 Erosion Protection at Conduit Outlets, for Froude numbers
up to 2.5.
Location #1: At proposed curb cut, upstream end of Swale #34.
Design Parameters:
100-yr Froude Number,
100-yr Design Discharge,
Diameter of Circular Conduit,
Width of Rectangular Conduit,
Height of Rectangular Conduit,
Tailwater Depth,
F
= 0.54
Q (cfs)=
21.2 cfs at Design Point 34.
D (ft)
= N.A.
W (ft)
= 12.0
H (ft)
= 1.43 (Assumed)
Y, (ft)
= 1.43 (See pg.16, Appendix)
Required Rock Size:
Select required rock size from Figure 5-7 for circular conduits and from
Figure 5-8 for rectangular conduits.
Figure 5-7 is valid for Q/D2.5 of 6.0 or less,
Figure 5-8 is valid for Q/WH1-5 of 8.0 or less.
Q/WH15 = 21.2/12(1.43)' 5 = 1.03 < 8.0, OK.
Q/WHO-5 = 21.2/12(1.43)1.5 = 1.48
Y,/H = 1.43/1.43 = 1.0
From Figure 5-8, Use Type L riprap for a distance of 3H downstream.
3H = 3(1.43)= 5.29 ft, Use a distance of 8 ft.
GS
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Use Ho
instead of H whenever culvert
has supercritical flow in the barrel.
**Use
Type L for a distance of
3H downstream.
FIGURE 5-8. RIPRAP EROSION
PROTECTION AT RECTANGULAR
CONDUIT OUTLET.
FIGURE 5-8 IS VALID FOR Q/ WHO'S
OF 8.0 OR LESS,
Y
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D= DESIGN DISCHARGE IN CFS
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W AND H=- WIDTH AND HEIGHT OF
RECTANGULAR CONDUIT IN FEET
Y. = TAILWATEF DEPTH
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Final Drainage Report Page 2
Stone Ridge Fourth Filing, Phase II
2.2 Site Description
Stone Ridge P.U.D. Fourth Filing, Phase II is approximately 8.322 acres and
' has historically been furrowed agricultural land. The site has been previously overlot
graded as part of previous Stone Ridge P.U.D. filings. The Fossil Creek Reservoir
Inlet is located east of the site across County Road 9 and flows from northwest to
' southeast.
2.3 Irrigation Ditches and Reservoirs
There are no irrigation laterals located on the Fourth Filing, Phase II site.
1 III. HISTORIC DRAINAGE BASIN
' 3.1 Major Basin Description
The site is located in the Foothills Basin (Basin G) and is included in the report
entitled Foothills Basin (Basin G) Drainage Master Plan, by Resource Consultants,
Inc., February, 1981. The master plan calls for an on -site detention facility for the
Stone Ridge P.U.D. site which was designed by RBD Inc. and included in the report
Stone Ridge P.U.D. Overall Site Detention Pond, March, 1994. The pond was
constructed as part of Stone Ridge P.U.D. Third Filing and is intended to detain all
developed stormwater within the Stone Ridge P.U.D..
3.2 Historic Drainage Patterns
The site has historically drained from west to east at a very gradual slope of
approximately 0.5%. Off -site flows enter Phase II of the Fourth Filing from the west
1 from Stone Ridge Fourth Filing, Phase I, Sub -Phase A.
IV. DEVELOPED DRAINAGE BASIN
4.1 Developed Conditions
The proposed development of the site includes:
• extension of a private drive,
• new water services and sanitary sewer,
• and improvements to temporary swale #34.
4.2 Design Criteria and References
Drainage criteria outlined in both the City of Fort Collins Storm Drainage Design
Criteria Manual.(SDDCM) and Storm Drainage Criteria Manual by the Urban Drainage
and Flood Control District have been referenced for this Final Drainage Study.
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Final Drainage Report Page 3
Stone Ridge Fourth Filing, Phase II
4.3 Hydrologic Criteria
The Rational Method has been used to estimate peak stormwater runoff from
the developed site. The initial 2-year and major 100-year design storms have been
used in the evaluation of the proposed drainage system. Rainfall intensity data for the
Rational Method has been taken from Figure 3-1 of SDDCM.
4.4 Hydraulic Criteria
The City of Fort Collins Storm Drainage Design Criteria has been referenced for
all hydraulic calculations. In addition, the following computer program has been
utilized:
• The computer program "Flowmaster" has been used to analyze
the capacity of proposed Swale # 34.
4.5 Drainage Concept
Drainage basins located on the Phase II site (Basins' 31-37) coincide with those
delineated on the Final Drainage Plan by RBD, Inc. for Stone Ridge P.U.D. Fourth
Filing, Phase I. Composite runoff coefficients and areas in all basins except Basin 34
have remained relatively unchanged from those calculated by RBD in the Final
Drainage Report for the Fourth Filing, Phase I.
Design Point 35 has been recalculated to reflect final runoff coefficients and
design flows from Basin 34. Final design flows from Basin 34 are less than those
I estimated in the Phase I, Final Drainage Report for developed conditions (See pages
11 and 13, Appendix) therefore downstream conveyance elements will not require re-
design.
1 Developed stormwater from Stone Ridge Fourth Filing, Phase II will be
conveyed overland in drive -over curb and gutter and in Swale #34 to existing open
grass -lined swales (#33, #35, #36 and #38) and the overall site detention pond located
in the northeast corner of the Stone Ridge P.U.D.. The existing temporary swale #34,
which was constructed as part of the Fourth Filing, Phase I, will be improved and will
' contain an underdrain due to a proposed slope of 0.60%.
Off -site stormwater from Phase I (Sub -Phase A) of the Fourth Filing will be
conveyed through Phase II to the existing overall site detention pond via proposed
Swale #34.
Storm sewer will not be required as part of the Fourth Filing, Phase II
improvements.
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Final Drainage Report Page 4
Stone Ridge Fourth Filing, Phase II
V. EROSION CONTROL
5.1 Erosion Control Plan
Permanent riprap will be provided at the proposed curb cut located at the
upstream end of Swale #34. The improved temporary Swale #34 shall be seeded
immediately upon completion with the permanent seed mix specified on the Grading
Plan.
' Temporary sediment control consisting of straw bale dikes will be used in Swale
#34 until permanent vegetation is established. A gravel filter will be required at the
curb cut and silt fencing installed adjacent to all swales.
VI. CONCLUSIONS
6.1 Compliance with Standards
All drainage analyses have been performed according to the City of Fort Collins
Storm Drainage Design Criteria Manual (SDDCM) and the Urban Drainage and Flood
Control District's Drainage Criteria Manual.
Let me emphasize here, that many of the hydraulic calculations for downstream
I street and swale capacities have been completed in connection with previous filings of
Stone Ridge P.U.D. by RBD, Inc.. These calculations are still valid because design
flows for Phase 2 of the Fourth Filing are the same or less than those estimated by
RBD for this phase. I would refer the reviewer to the report, Final Drainage and
Erosion Control Study for Stone Ridge P.U.D. Fourth Filing, Phase I for verification of
downstream capacities, these do not require modification as part of Phase 2 due to
consistent design flows.
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' Final Drainage Report Page 5
Stone Ridge Fourth Filing, Phase II
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REFERENCES
a
1. Final Drainage and Erosion Control Study for Stone Ridge
P.U.D. Fourth Filing, Phase I, Fort Collins, Colorado, RBD,
Inc. Engineering Consultants, March 3, 1995.
! 2. Foothills Basin (Basin G) Drainage Master Plan, Fort
Collins, Colorado, Resource Consultants, Inc., February
1981.
3. Storm Drainage Design Criteria and Construction
Standards, City of Fort Collins, Colorado, May, 1984.
4. Drainage Criteria Maunal, Urban Drainage and Flood
Control District, Wright -McLaughlin Engineers, Denver,
Colorado, March, 1969.
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Final Drainage Report
Stone Ridge Fourth Filing, Phase II
Page 6
APPENDIX
PAGE
Developed On -Site Hydrology ............................................... 1 - 8
Developed Hydrology
Stone Ridge Fourth Filing, Phase I ....................................... 9 -13
Design of Swales................................................................. 14 -18
StreetCapacity.................................................................... 19 -24
Design of Riprap Outlet Protection .................................... 25- 26
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