HomeMy WebLinkAboutECKERD DRUG, COLLEGE & DRAKE - PDP/FDP - 25-03 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORT[1
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APPENDIX E
FIGURES AND TABLES
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Cost Est
EROSION CONTROL COST ESTIMATE
Project: ECKERDS DRUG STORE
Prepared by: SB
ITEM
IQUANTITY
JUNIT
COST/UNIT
ITOTAL COST
Silt Fence
385
LF
$3
$1,155
Straw Bale Barrier
2
EA
$150
$300
Gravel Inlet Filter
0
EA
$150
$0
Construction Entrance
1
EA
$550
$550
Subtotal
Contingency (50%)
Total
$2,005
$1,003
$3,008
CITY RESEEDING COST
Reseed/Mulch
1.7
ACRE
$650
$1,105
Subtotal
Contingency (50%)
Total
$1,105
$553
$1,658
EROSION CONTROL ESCROW AMOUNT $3,008
Page 1
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North Star Design
1200 Carousel Drive, Suite 201
Windsor, CO 80550
CONSTRUCTION SEQUENCE
STANDARD FORM C
PROJECT: ECKERDS DRUG STORE
COMPLETED BY: SB DATE: 22-Jul-03
Indicate by use of a bar line or symbols when erosion control measures will be installed. Major modifications to an
approved schedule may require submitting a new schedule for approval by the City Engineer.
2003
2004
MONTH
J
A
S
0
N
D
1 J
F
M
A
M
J
Demolition
Grading
Wind Erosion Control:
Soil Roughing
Perimeter Barrier
s
Additional Barriers
Vegetative Methods
Soil Sealant
Other
Rainfall Erosion Control
Structural:
Sediment Trap/Basin
Alto
4
Inlet Filters
Straw Barriers
Silt Fence Barriers
Sand Bags
Bare Soil Preparation
Contour Furrows
Terracing
Asphalt/Concrete Paving
Other
Vegetative:
Permanent Seed Planting
Mulching/Sealant
an
Ell
Temporary Seed Planting
Sod Installation
Netti ng s/Mats/Blankets
Other
BUILDING CONSTRUCTION
STRUCTURES: INSTALLED BY: CONTRACTOR MAINTAINED BY: DEVELOPER
VEGETATION/MULCHING CONTRACTOR: TO BE DETERMINED BY BID
DATE SUBMITTED: 6/30/03 APPROVED BY CITY OF FORT COLLINS ON:
Page 1
North Star Design
700 Automation Drive, Unit I
Windsor, CO 80550
EFFECTIVENESS CALCULATIONS
PROJECT:
ECKERDS DRUG STORE
STANDARD FORM B
COMPLETED BY:
SB
DATE: 22-Jul-03
EROSION CONTROL
C-FACTOR
P-FACTOR
METHOD
VALUE 'VALUE
COMMENT
BARE SOIL
1.00
1.00
SMOOTH CONDITION
ROUGHENED GROUND
1.00
0.90
SEDIMENTBASIN
1.00
0.50
ROADS/WALKS
0.01
1.00
GRAVEL FILTERS
1.00
0.80
PLACED AT INLETS
SILT FENCE
1.00
0.50
STRAW MULCH
0.06
1.00
ESTABLISHED GRASS
0.08
1.00
STRAW BARRIERS
1.00
0.80
EFF = (I -C*P)* 100
MAJOR
SUB
BASIN AREA
EROSION CONTROL METHODS
BASIN
BASIN
(Ac)
1
0.19
BARE SOIL
0.02 Ac.
ROADS/WALKS
0.15 Ac.
STRAW MULCH
0.00 Ac.
ROUGHENED GROUND
0.02 Ac.
ABLISHED GRASS
0.00 Ac.
C-FACTOR
0.22
P-FACTOR
L
0.48
= (I-C*P)* l00 =
89.6%
2
1.02
BARE SOIL
0.27 Ac.
ROADS/WALKS
0.48 Ac.
STRAW MULCH
0.00 Ac.
ROUGHENED GROUND
0.27 Ac.
ESTABLISHED GRASS
0.00 Ac.
NET C-FACTOR
0.53
NET P-FACTOR
0.38
EFF = (1-C*P)* 100 =
79.7%
3
_
0.37
BARE SOIL
0.02 Ac.
ROADS/WALKS
0.33 Ac.
STRAW MULCH
0.00 Ac.
ROUGHENED GROUND
0.02 Ac.
ESTABLISHED GRASS
0.00 Ac.
NET C-FACTOR
0.12
NET P-FACTOR
0.95
EFF = (I-C*P)* 100 =
88.9%
4
0.08
BARE SOIL
0.04 Ac.
ROADS/WALKS
0.00 Ac.
STRAW MULCH
0.00 Ac.
ROUGHENED GROUND
0.04 Ac.
ESTABLISHED GRASS
0.00 Ac.
NET C-FACTOR
1.00
NET P-FACTOR
0.48
EFF, = (I-C*P)* 100 =
52.5%
' TOTAL AREA = 1.66 ac
TOTAL EFF = 81.6%
REQUIRED PS = 78.4%
' Erosion.xls 1 of 1
North Star Design
700 Automation Drive, Unit I
Windsor. CO 80550
LOCATION: ECKERDS DRUG STORE
PROJECT NO: 192-04
COMPUTATIONS BY: SB
SUBMITTED BY: North Star Design, Inc.
DATE: 7/22/03
RAINFALL PERFORMANCE STANDARD EVALUATION
PROJECT: ECKERDS DRUG STORE STANDARD FORM A
COMPLETED BY: SB DATE: 22.1ul-03
DEVELOPED
ERODIBILITY
Asb
Lsb
Ssb
Ai * Li
Ai * Si
Lb -
Sb
PS
SUBBASIN(s)
ZONE
(AC)
(FT)
(%)
(FT)
1
MODERATE
0.19
110
1.5
20.9
0.3
2
MODERATE
1.02
520
0.9
530.4
0.9
3
MODERATE
0.37
240
0.9
88.8
0.3
4
MODERATE
0.08
15
5.0
1.2
0.4
Total
1
1 1.66
1
1
1 641.30
1 1.94
1 386.3
1.2
78.4%
Ash = Sub -basin area
Lsb = Sub -basin flow path length
Ssb = Sub -basin slope
Lb = Average flow path length = sum(Ai Li)/sum(Ai)
Sb = Average slope = sum(Ai Si)/Sum (Ai)
PS is taken from Table 8-a (Table 5.1, Erosion Control Reference Manual) by interpolation.
An Erosion Control Plan will be developed to contain 78.4% of the rainfall sedimentation
that would normally flow off a bare ground site during a 10-year, or less, precipitation event.
Erosion.xls 1 of 1
' APPENDIX D
EROSION CONTROL CALCULATIONS
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1
[1
I
7/22/03
LOCATION:
JOB NO:
COMPUTATIONS BY:
SUBMITTED BY:
DATE:
100-Year WSEL.
WATER QUALITY CAPTURE VOLUME
ECKERDS DRUG STORE
192-04
SB
North Star Design, Inc.
7/22/03
STAGE / STORAGE TABLE
WQ POND
Stage
(ft)
Surface
Area
(ft)
Incremental
Storage
(ac-ft)
Total
Storage
(ac-ft)
5015.3
0
5015.5
324
0.000
0.000
5015.75
1529
0.005
0.005
5016.00
2616
0.012
0.017
5016.20
3243
0.013
0.031
5016.25
3399
0.004
0.034
WQVOL.xls
r r r r r i■■i r r r r r r r r r r� r r
7/22/03
WATER QUALITY CAPTURE VOLUME
LOCATION: ECKERDS DRUG STORE
JOB NO: 192-04
COMPUTATIONS BY: SB
SUBMITTED BY: North Star Design, Inc.
DATE: 7/22/03
From Urban Strom Drainage Criteria Manual, September 1999
Use: 40 -hour brim -full volume drain time for extended detention BASIN
Water Quality Capture Volume = WQCV = a * (0.91 * I3 - 1.19 * I2 + 0.78 * I )
I = Imperviousness
Required storage = WQCV / 12 * tributary drainage area
Hour Brim Full = 40
a= 1
Trib.
% Imperv.
WQCV
Req. Storage
DWQ
req. vol
req. area/row
area
(in. of runoff)
Req. Stor *1.2
(in 2/row)
(ac)
(I)
from Fig. 5-1
(ac-ft)
(ft)
(ac-ft)
from Fig. 5-3
WQ Required 1.67
76
0.305
0.042
0.95
0.051
0.351
WQ Proposed 1.07
79
0.322
0.029
0.95
0.034
0.238
WQ outlet sizing for pond 1
From Figure 5,
for 1/2 in. hole diameter
Area / Hole = 0.196 in
# of columns = 1
Area provided/row = 0.196 in
Area Required/row = 0.238 in2
Use 1 columns of 1/2" diameter holes
WQVOL.xls
APPENDIX C
WATER QUALITY CALCULATIONS
I
CURB CUT
RECTANGULAR WEIR EQUATION
CE REFERENCE MANUAL - 7TH - LINDEBURG 19-10-14
LOCATION: ECKERDS DRUG STORE
PROJECT NO: 192-04
COMPUTATIONS BY: SB
SUBMITTED BY: North Star Design, Inc.
DATE: 7/22/03
CURB CUT MINIMUM WIDTH
Q. = (2/3)*Cl.b*sgrt(2g)*HA(1.5)
where Q. = flow (cfs)
Ca = discharge coefficient 0.62
g = gravitational acceleration = 32.2 ft/s
b= width of curb opening
H= height of curb opening
Q required = 9.8 cfs
h = 0.70 ft
solve for: b = 5.00 ft
check: Q = 9.71 cfs
USE 5.0 FOOT CURB CUT
FIND ACTUAL DEPTH:
h = 0.71 ft
1
1
M = = = i = M = = M = = M = M M
North Star Design, Inc.
700 Automation Drive, Unit I
Windsor, CO 80550
LOCATION:
PROJECT NO:
COMPUTATIONS BY:
DATE:
ECKERDS DRUG STORE
192-04
SB
7/22/03
RATIONAL METHOD PEAK RUNOFF
(100-YEAR)
DIRECT RUNOFF
CARRY OVER
TOTAL
Inlet Capacity
REMARKS
Design
Point
SUBBASIN
DESIGNATION
A
(ac)
C1W
TOC,w
(min)
i
(in/hr)
Qim
(cfs)
from
Design
Point
Qim
(cfs)
Qjw Total
(cfs)
(cfs)
EXISTING
1.67
1.00
5.0
9.95
16.59
16.59
PROPOSED
1
1
0.19
0.97
5.0
9.95
1.88
1.88
2
2
1.07
1.00
5.4
9.69
10.33
10.33
3
3
0.38
1.00
5.0
9.95
3.79
3.79
4
4
0.08
0.31
5.0
9.95
0.26
0.26
"Composite
1.72
1.00
5.4
9.69
16.72
16.72
16.2 cfs without Sinclair station area
Q=CiA
Q = peak discharge (cfs)
C = runoff coefficient
i = rainfall intensity (in/hr) from IDF curve
A = drainage area (acres)
Flow.xls Q100
North Star Design, Inc.
700 Automation Drive, Unit I
Windsor, CO 80550
LOCATION:
PROJECT NO:
COMPUTATIONS BY:
DATE:
ECKERDS DRUG STORE
192-04
SB
7/22/03
RATIONAL METHOD PEAK RUNOFF
(10-YEAR)
DIRECT RUNOFF
CARRY OVER
TOTAL
Inlet Capacity
REMARKS
Design
Point
SUBBASIN
DESIGNATION
A
(ac)
C)a
TOC,
(min)
i
(in/hr)
Qno
(cfs)
from
Design
Point
Q10
(cfs)
Quo Total
(cfs)
(cfs)
EXISTING
1.67
0.88
5.0
4.87
7.14
7.14
PROPOSED
1
l
0.19
1 0.78
5.0
4.87
0.74
0.74
2
2
1.07
0.83
7.6
4.16
3.67
3.67
3
3
0.38
0.88
5.0
4.87
1.63
1.63
4
4
0.08
0.25
5.0
4.87
0.10
0.10
"Composite
1.72
0.81
7.9
4.16
5.78
5.78
5.6 cfs without Sinclair station area
Q=CiA
Q = peak discharge (cfs)
C = runoff coefficient
i = rainfall intensity (in/hr) from IDF curve
A = drainage area (acres)
FlowAs O70
LOCATION:
PROJECT NO:
COMPUTATIONS BY:
DATE:
ECKERDS DRUG STORE
192-04
SB
7/22/03
TIME OF CONCENTRATION
100-YEAR
SUB -BASIN DATA
INITIAL / OVERLAND TIME
(t�
TRAVEL TIME / CHANNEL FLOW
(t,)
t, CHECK
(URBANIZED BASIN)
FINAL
t�
REMARKS
DESIGN
POINT
SUBBASIN
DESIGNATION
(1)
Area
(ac)
(2)
C*Cf
(Cf= 1.25)
(3)
Length
(ft)
(4)
Slope
(%)
(5)
t;
(min)
(6)
Length
(ft)
(7)
Slope
(%)
(8)
V
(ft/s)
(9)
t,
(min)
(10)
t,
(min)
(11)
Total L
(ft)
(12)
t� (L / 180)+10
(min)
(13)
(min)
(14)
EXISTING
1.67
1.00
35
2.0
0.88
350
2.0
2.8
2.06
2.9
385
12.1
5.0
PROPOSED
1
1
0.19
0.97
60
1.5
1.61
50
1.5
2.4
0.34
1.9
110
10.6
5.0
2
2
1.07
1.00
70
2.0
1.24
450
o.8
1.8
4.19
5.4
520
12.9
5.4
3
3
0.38
1.00
70
2.5
1.15
170
0.7
1.7
1.69
2.8
240
11.3
5.0
4
4
0.08
0.31
15
5.0
3.34
0
2.0
2.8
0.00
3.3
15
10.1
5.0
**Composite
1.72
1.00
70
2.0
1.24
450
0.8
1.8
4.19
5.4
520
12.9
5.4
EQUATIONS:
tc=ti+4
t;=[1.87(1.1-C*Cf)Los]/Sua
t,=L/V where V=C,*Sw5
(C from Table RO-2)
final t, = minimum of t; + t, and urbanized basin check
M M M M M M M M M M M M r M M M M M M
LOCATION:
PROJECT NO:
COMPUTATIONS BY:
DATE:
ECKERDS DRUG STORE
192-04
SB
7/22/03
TIME OF CONCENTRATION
10-YEAR
SUB -BASIN DATA
INITIAL / OVERLAND TIME
W
TRAVEL TIME / CHANNEL FLOW
(tt)
t, CHECK
(URBANIZED BASIN)
FINAL
t,
REMARKS
DESIGN
POINT
SUBBASIN
DESIGNATION
(1)
Area
(ac)
(2)
C*Cf
(Cf= 1.0)
(3)
Length
(ft)
(4)
Slope
(%)
(5)
ti
(min)
(6)
Length
(ft)
(7)
Slope
M(ft/s)
(8).
V
(9)
t
(min)
(10)
t,
(min)
(11)
Total L
(ft)
(12)
t,=(L / 180)+10
(min)
(13)
(min)
(14)
EXISTING
1.67
0.88
35
2.0
1.94
350
2.0
2.8
2.06
4.0
385
12.1
5.0
PROPOSED
1
1
0.19
0.78
60
1.5
4.07
50
1.5
2.4
0.34
4.4
110
10.6
5.0
2
2
1.07
0.83
70
2.0
3.39
450
0.8
1.8
4.19
7.6
520
12.9
7.6
3
3
0.38
0.88
70
2.5
2.52
170
0.7
1.7
1.69
4.2
240
11.3
5.0
4
4
0.08
0.25
is
5.0
3.60
0
2.0
2.8
0.00
3.6
15
10.1
5.0
**Composite
1.72
0.81
70
2.0
3.66
450
0.8
1.8
4.19
7.9
520
12.9
7.9
EQUATIONS:
t;=[1.87(1.1-C*Cf)L05I/Su3
t,=L/V where V=C,*SH5
(C, from Table RO-2)
final t, = minimum of t; + 4 and urbanized basin check
i NoiDesi�
700 Automation Drive, Unit I
Windsor, CO 80550 '
LOCATION:
PROJECT NO:
COMPUTATIONS BY:
DATE:
RUNOFF COEFFICIENTS & % IMPERVIOUS
ECKERDSDRUG STORE
192-04
SB
7/22/03
Recommended % Impervious from Urban Storm Drainage Criteria Manual
Streets, parking lots (asphalt):
Sidewalks (concrete):
Roofs:
Lawns (Average 2-7%, heavy soil):
Runoff
%
'coefficient
Impervious
C
0.95
100
0.95
90
0.95
90
0.25
0
SUBBASM
DESIGNATION
TOTAL
AREA
(ac.)
TOTAL
AREA
(sq.ft)
ROOF
AREA
(sq.ft)
PAVED
AREA
(sq.ft)
SIDEWALK
AREA
(sq.ft)
LANDSCAPE
AREA
(sq.ft)
RUNOFF
COEFF.
(CIO)
RUNOFF
COEFF.
(Cim)
Impervious
EXISTING
1.67
72,640
14,677
45,031
5,572
7,359
0.88
1.00
87
PROPOSED
1
0.19
8,463
0
6,289
101
2,073
0.78
0.97
75
2
1.07
46,400
15,282
22,190
771
8,157
0.83
1.00
79
3
0.38
16,571
310
14,227
414
1,620
0.88
1.00
90
4
0.08
3,693
0
0
0
3,693
0.25
0.31
0
--Composite
1.72
75,127
15,593
42,706
1,286
15,543
0.81
1.00
77
"NU I L: I he composite area includes a small area (UM acres) of the Sinclair station
Fiow.xis Cval
I]
I
APPENDIX B
' HYDROLOGIC & HYDRAULIC COMPUTATIONS
1
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No Text
I
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APPENDIX A
VICINITY MAP
W
7. REFERENCES
1. City of Fort Collins, "Storm Drainage Criteria Manual", (SDCM), dated March
1999.
2. Urban Drainage and Flood Control District, "Urban Storm Drainage Criteria
Manual", Volumes 1 and 2, dated June 2001, and Volume 3 dated September
2001.
H.
' calculations are included in Appendix D of this report.
The erosion control escrow amount is $3,000.
5.2. Specific Details
To limit the amount of silt leaving the site several erosion control measures shall be
implemented during construction. Straw bales will be used where appropriate and the
east boundary shall have silt fence installed. A vehicle tracking pad shall be installed at
' the connection to Thunderbird Drive to control the mud being tracked onto the existing
pavement. During overlot grading, disturbed areas are to be kept in a roughened
' condition and watered to reduce wind erosion. The water quality pond will be used as
sediment traps during construction.
' 6. CONCLUSIONS
' 6.1. Compliance with Standards
All computations that have been completed within this report are in compliance with the
City of Fort Collins Erosion Control Reference Manual for Construction Sites and the
Storm Drainage Design Criteria Manual. Variances being requested for the proposed
' Eckerds site are: to reduce the minimum water quality capture volume from 0.051 acre-
feet to 0.034 acre-feet; to reduce the minimum freeboard requirement from 1.0 feet to 0.6
' feet.
6.2. Drainage Concept
Conveyance elements have been designed to convey required flows to the existing curb
and gutter of the adjacent streets and to minimize future maintenance. Variances to the
water quality capture volume and minimum freeboard requirement are being sought.
' If, at the time of construction, groundwater is encountered, a Colorado Department of
Health Construction Dewatering Permit will be required.
' 5
I
' Basin 1 contains the majority of the north parking lot and access drive. Runoff from this
' basin will be conveyed via concrete pan and curb and gutter to the East Drake Road curb
and gutter. Basin 1 runoff is 0.74 cfs. for the minor storm and 1.9 cfs for the major storm.
Basin 2 contains the portion of the site that will be treated by the water quality pond,
including the proposed building and adjacent parking and walks. Runoff from this basin
1
is conveyed to the water quality pond via concrete pans and curb and gutter. From there,
the water is released into the East Drake Road curb and gutter. Runoff from Basin 2 is.
'
3.76 cfs for the 10-year storm and 10.3 cfs for the 100-year storm.
Basin 3 contains the south access drive and parking. Runoff from this basin will be
Jconveyed
via concrete pan and curb and gutter to the Thunderbird Drive curb and gutter.
Runoff from Basin 3 is 1.63 cfs for the 10-year storm and 3.8 cfs for the 100-year storm.
Basin 4 contains landscaping area adjacent to the existing residential properties. Runoff
from this basin will sheet flow onto the adjacent properties as it has historically done.
Total runoff from Basin 4 is 0.1 cfs for the 10-year storm and 0.3 cfs for the 100-year
storm.
4.3. Drainage Summary
Drainage facilities located outside of the right-of-way (including the water quality pond,
existing and proposed storm drain systems, and the pond outlet) will be maintained by the
owners of the property. A water quality pond is proposed that will treat a portion of the
site. The treated water will be released into the East Drake Road curb and gutter. The
remainder of the site will release untreated to the curb and gutter of the adjacent
roadways.
I 5. EROSION CONTROL
' 5.1. General Concept
This site lies within the Moderate Rainfall and Wind Erodibility Zone per the City of Fort
Collins and into adjacent properties. Potential also exists for tracking of mud onto
existing streets which could then wash into existing storm systems. The required
' performance standard for the site is 78.4%. During construction and after paving, this
figure has been exceeded with the use of silt fence, inlet filters, straw bales, and by using
the water quality pond as a sediment trap during construction. All erosion control
4
I
There are no proposed storm pipes with this design. All basins will release into the
' existing curb and gutter of the adjacent streets.
4. DRAINAGE FACILITY DESIGN
4.1. General Concept
Water quality is required for this site. However, due to the flat slope of the site, the
' adjacent existing improvements that are to remain, and the absence of any nearby storm
sewer system, the proposed drainage concepts presented in this report and on the
construction plans do not provide for the minimum requirement for stormwater quality
treatment of the proposed site. Runoff from a portion of the site will be routed to the
water quality pond and the treated water will be released into East Drake Road. The
' remainder of the site will be released into the curb and gutter of East Drake Road and
Thunderbird Drive without water quality extended detention.
A portion of the proposed site will be routed to the proposed water quality pond. This
pond will be incised into the berm and will have a water quality outlet structure mounted
' in a headwall. A 2' concrete channel will convey the clean water to the existing East
Drake Road curb and gutter. There will be no pipe outlet for the pond. The wall will act
' as the spillway and will overtop into the proposed channel in larger storms.
A variance is being sought to reduce the required water quality extended detention from
0.051 acre-feet to 0.034 acre-feet. A variance is also being sought to reduce the required
freeboard in the pond from 1' to the 0.6' that is provided. The flat slope of the site, the
adjacent existing improvements that are to remain, and the absence of any nearby storm
sewer system all contribute to the limitations of an on -site water quality pond. Please
' note that there is currently no water quality detention for the existing site or any of the
adjacent properties. Therefore, while the minimum requirement for the site will not be
met, there will be a marked improvement in water quality detention when compared with
the existing site.
4.2. Specific Flow Routing
A summary of the drainage patterns within each basin is provided in the following
paragraphs.
1 3
development, on site detention is not required. Water quality extended detention,
however, is required on this site.
2.2. Sub -basin Description
' There are three drainage basins for the proposed site. Basin 1 drains via curb and gutter
and concrete pans to the proposed water quality pond, and then is conveyed to the East
Drake Road curb and gutter via a concrete channel. Runoff from Basin 2 is released
directly into East Drake Road via curb and gutter and concrete pans. Basin 3 runoff is
' conveyed to Thunderbird Drive curb and gutter via gutter flow. See Section 4 of this
report for a more detailed explanation of subbasin flows.
3. DRAINAGE DESIGN CRITERIA
3.1. Regulations
1 This report was prepared to meet or exceed the "City of Fort Collins Storm Drainage
Design Criteria Manual' specifications. Where applicable, the criteria established in the
"Urban Storm Drainage Criteria Manual" (UDFCD), 2001 has been used.
3.2. Development Criteria Reference and Constraints
The runoff from this site has been routed to conform to the requirements of the City
Stormwater Department. Detention is not proposed for this site. Water quality facilities
' are required for the site.
3.3. Hydrologic Criteria
Runoff computations were prepared for the 10-year minor and 100-year major storm
frequency utilizing the Rational Method. All hydrologic calculations associated with the
basins are included in Appendix B of this report. Water quality volume was calculated
using the method recommended in the "Urban Storm Drainage Criteria Manual'. All
water quality calculations are included in Appendix C of this report.
' 3.4. Hydraulic Criteria
' All hydraulic calculations within this report have been prepared in accordance with the
City of Fort Collins Drainage Criteria and are included in Appendix B of this report.
1 2
1. GENERAL LOCATION AND DESCRIPTION
' 1.1. Location
' The proposed Eckerds Drug Store is located in Fort Collins at the southeast corner of the
intersection of East Drake Road and College Avenue. This project is located in the
Northwest Quarter of Section Twenty-five, Township Seven North, Range Sixty-nine
West of the Sixth Principal Meridian, in the City of Fort Collins, Larimer County,
1 Colorado. See the location map in Appendix A.
The site is bounded on the north by East Drake Road, on the east by existing residential
lots, on the south by Thunderbird Drive, and on the west by South College Avenue.
There is an existing Sinclair Gas Station on the northwest comer of the site, existing
1 Moot House Restaurant on the southwest corner of the site, and an existing State Farm
Insurance office on the northeast comer of the site.
' 1.2. Description of Property
The project consists of approximately 1.7 acres of land. The proposed improvements on
this site consist of a single -story building with associated drives, walks, and parking.
Access is obtained on the north from East Drake Road, on the south from Thunderbird
Drive, and on the west from the frontage road. No portion of the proposed project is
within a designated floodplain area.
Existing development on the site includes a single story brick building and a motel with a
single story office and a small pool along with drives, walk, and parking. The southern
portion of the site currently drains into Thunderbird Drive and the northern portion of the
site currently drains into East Drake Road. There are currently no existing detention or
water quality structures on the site or on any of the adjacent sites.
' 2. DRAINAGE BASINS AND SUB -BASINS
2.1. Major Basin Description
' The proposed development lies within the Spring Creek Drainage Basin. Because this is
a redevelopment area and the imperviousness on site is not being increased with this
1
I
TABLE OF CONTENTS
TABLEOF CONTENTS....................................:..........................................................................
iii
'
1.
GENERAL LOCATION AND DESCRIPTION
1.1 Location...................................................................................................................1
1.2 Description of Property............................................................................................1
2.
DRAINAGE BASINS AND SUB -BASINS
2.1 Major Basin Description..........................................................................................2
'
2.2 Sub -Basin Description.............................................................................................2
3.
DRAINAGE DESIGN CRITERIA
'
3.1 Regulations..............................................................................................................2
3.2 Development Criteria Reference and Constraints....................................................2
3.3 Hydrologic Criteria..................................................................................................3
3.4 Hydraulic Criteria....................................................................................................3
4.
DRAINAGE FACILITY DESIGN
4.1 General Concept.......................................................................................................3
4.2 Specific Flow Routing.............................................................................................4
4.3 Drainage Summary ...................................................................................................5
5.
EROSION CONTROL
'
5.1 General Concept......................................................................................................5
5.2 Specific Details
........................................................................................................5
6.
CONCLUSIONS
6.1 Compliance with Standards....................................................................................6
6.2 Drainage Concept.....................................................................................................6
7.
REFERENCES
...........................................................:........................................................7
APPENDICES
A Vicinity Map
B. Hydrologic & Hydraulic Computations
C Water Quality Pond Sizing
D Erosion Control Calculations
E Figures and Tables
1
North Star
design, inc.
July 22, 2003
Basil Hamdan
City of Fort Collins Stormwater
'
700 Wood Street
Fort Collins, CO 80522-0580
RE: Final Drainage and Erosion Control Report for Lots 2, 4, & 6 of Thunderbird
' Estates 6`h Subdivision (Eckerds Drug Store)
Dear Basil,
1
I am pleased to submit for your review and approval, this Final Drainage & Erosion Control
' Report for Lots 2, 4, & 6 of Thunderbird Estates 6`h Subdivision, hereafter referred to as Eckerds
Drug Store. I certify that this report for the drainage design of Eckerds Drug Store was prepared
in accordance with the criteria in the City of Fort Collins Storm Drainage Manual.
I appreciate your time and consideration in reviewing this submittal. Please call if you have any
questions.
' Prepared by: Reviewed By: ~QJ `� Y••'��r`S�({f'�,�'
3
Shane Boyle, EIT Patricia Kroetch, E
' North Star Design, Inc. North Star Design, Inc.
I
' 700 Automation Drive, Unit I Windsor, Colorado 80550
970-686-6939 Phone , 970-686-1 188 Fax
i
FINAL DRAINAGE AND EROSION CONTROL REPORT
LOTS 2149 & 6 OF
THUNDERBIRD ESTATES 6TH SUBDIVISION
(ECKERDS DRUG STORE)
Prepared for:
HUNT DOUGLAS
5100 W. Kennedy Blvd, Suite 225
Tampa, FL 33609
Prepared by:
North Star Design
700 Automation Drive, Unit I
Windsor, Colorado 80550
(970)686-6939
July 23, 2003
Job Number 192-04