HomeMy WebLinkAboutDrainage Reports - 02/14/2003"ROPFAI TY OF JUL 2 1 M
FORT COLLINS 11TRITM8FINAL �
DRAINAGE, EROSION CONTROL & EXTENDED DETENTIJN REPORT
FOR
CENTERPOINT PLAZA
PHASE 1
i
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Dade ZLJ V
SITUTATE IN THE SPRING CREEK DRAINAGE BASIN
PREPARED FOR
FRAZIER & COMPANY
FEBRUARY 14, 2003
PREPARED BY
STEWART & ASSOCIATES, INC.
103 SOUTH MELDRUM STREET
P.O. BOX 429
FORT COLLINS, CO 80522
TEL: 970.482.9331
FAX: 970.482.9382
CEMIRPUINT W dig Nt dm
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' STEWART&ASSOCIATES
February 14, 2003 Consulting Engineers and Surveyors
Mr. Basil Hamdan
Stormwater Utilities
City of Fort Collins
'
P.O. Box 580
Fort
Collins, CO 80522-0580
' Dear Basil,
EXISTING SITE:
1 The following is a Final Drainage, Erosion Control, and Extended Detention Report for
' Phase I of Centerpoint Plaza. Centerpoint Plaza is a Replat of Lot 1, Nor -Colo Subdivision and a
Tract of Land situate in the Northwest 1/4 of section 20, Township 7 North, Range 68 West of
the Sixth P.M., Fort Collins, Larimer County, Colorado. The total area is 7.0 acres net. This
' area does include 40.5 feet of Timberline Road and 3.0 feet of Midpoint Drive. This project is
located in the City of Fort Collins Spring Creek Drainage Basin. Phase I area is 1.62 acres which
is the Northern part of Lot 1.
This project is bounded on the West by Timberline Road; on the North by Midpoint
Drive; on the East by Lot 2, Nor -Colo Subdivision, which is undeveloped; and on the South by
t the Burlington Northern Railroad. There are no offsite flows from the North, East or South. A
recently updated (February, 2002) Spring Creek Master Drainage Plan shows that there is a Qloo
of 417 c.f.s. that flows across this site from the Southwest overflow of Timberline Road. They
show a ponded WSEL of4916.8 feet at the railroad tracts on Timberline. Also, the limits of that
study end at Timberline Road.
' On Lot 3 there is an existing one-story warehouse building with an asphalt parking area
and asphalt driveway from Midpoint Drive. There is also an existing railroad spur on the East
side of the building. The site West of this existing building is grass, bare ground, and weeds.
' The historic slope of this site is Northwest to Southeast. A small portion flows to Midpoint
Drive to the existing culvert; then North is a borrow ditch along Timberline Road to Spring
Creek. All of Timberline Road also flows South to North to the existing culvert. Because the
' City at conceptual review requested all runoff be directed to the Southeast corner of this project
we are considering the Historic and also the developed site as one basin. The average slope of
this site is 1.25%.
There is an existing small retention pond located at the Southeast corner of Lot 3. Runoff
is stored there until it reaches an elevation of 4908. At that elevation, runoff is to an old
irrigation ditch that is not being currently used for irrigation. This ditch is not being maintained.
The irrigation ditch runs East under the railroad spur in a 24" CMP, then East along the old fence
line toward the Larimer County Detention Center. At the "Center" the runoff is redirected to a
' retention pond developed by the "Center." Runoff from the West was included in the County's
Drainage Report. This pond is temporary until the County develops their site more. Then the
' runoff will be connected to the existing drainage channel along the developed lots in Prospect
East, which routs the runoff to the Poudre River. The existing irrigation ditch has captured and
James H. Stewart and Associates, Inc.
' rcN RPOM'rMd,g,AA. 103 S. Meldrum Street • P.O. Box 429 • Ft. Collins, CO 80522
970/482-9331 • Fax 970/482-9382
I
1 carried runoff since it was constructed. It has a prescriptive use easement and has been in
existence for many, many years.
DRAINAGE CRITERIA:
' Due to the small size of this site, the Rational Method has been utilized to determine peak
runoff rates and required detention pond volumes. The release rate is the two-year Historic rate.
' Design factors used are in accordance with the recommendations of the City of Fort
Collins Storm Drainage Criteria and Construction Standards Manual.
' DEVELOPED SITE:
This project is proposing to develop one office/storage building with parking, access
' drive, and landscaping. The building is Building "A" and is located at the North end of Lot 1 of
Centerpoint Plaza. The developer will build out the balance of Centerpoint Plaza when they are
no longer restricted by the City's 2% regulation, which will be when Timberline Road is
1 designed and constructed from Prospect Street to Drake Road.
A final drainage plan and report has been completed for this Total Site, being Lots 1, 2,
and 3, but have not yet been approved by the City at this time. Because the site does not meet
the City's 2% development requirement the developer is being required to submit utility plans
' and drainage plans for one building only. Therefore we have recalculated this project for the one
building only and have moved the detention pond South of the proposed parking area. This pond
is sized for the Phase 1 area and includes extended detention. The outlet of this pond will flow
South in a swale then Southeast to the existing prescriptive drainage/irrigation ditch used for the
overall development.
' Offsite flow of Qia, = 417 c.f.s. flow across the railroad track and Timberline road at our
Southwest corner of the site. We were told that the railroad track acted as a dike for runoff on the
West side of Timberline and that all the water from the Southwest was forced to cross at the low
1 point which was stated as being the railroad and Timberline Road. We surveyed the elevation of
the Southwest rail and actually found the low point in the railroad -tracks to be 100 feet West of
the center of Timberline. Our survey elevations are included at the end of this report. The low
' elevation was at 2916.0. The centerline of Timberline Road and the railroad is at elevation
4916.4. There is about 370 feet of track lower than the said centerline. Any runoff that flows
over the tracts West of the centerline of Timberline cannot get to our site because it is lower than
' our site by two feet or more.
Using the Weir equation for the railroad and the average depth of the Weir at 16.25 feet,
t 67 C.F.S. can overtop the railroad before it can cross over at Timberline to our site. Therefore,
the 417 C.F.S. is now down to 350 C.F.S. After elevation of 16.4 is reached, runoff flow will
overtop Timberline Road. 1 again used the Weir equation using elevation of 16.4 as the
overtopping elevation and added 40 more feet of length to the Weir due to overtopping the road
to the East. Length of Weir is now 410 LF. Because the Spring Creek drainage study showed
417 C.F.S., I used this number for the Weir equation. Both Weir Sections are shown on sheets 9
and 10 of this report. Using a ratio flow overtopping Timberline and flowing East is 40.9 C.F.S.
Now before this runoff can enter our site, it flows into an existing Swale (created by past runoff)
' CENTE0.MINT rm ft tdoc
1 11
' that flows North along Timberline Road to Spring Creek. This Swale slopes 1%. I calculated the
capacity of this existing Swale to be 95 C.F.S., which exceeds the estimated flow. This Swale
cross-section and design is shown on sheet 12 in this report and on sheet 4 of 8 of the Utility
Plans. This is more than double the calculated flow of 40.9 C.F.S. that reaches the Swale.
Engineering no longer wants the walk constructed on Timberline Road therefore we are final
' grading to match that original design at the right-of-way line. This creates a new Swale
configuration between the final graded area and the asphalt. I calculated the capacity of the
Swale to be 104 C.F.S. This is also more than the design capacity. This Swale's design and
cross-section are on sheet 11 of this report and also shown on sheet 4 of 8 of the Utility Plans.
The results are that the existing Swale and design Swale have the same effect and do not force
water elevation changes back to Timberline or cause any other downstream effects that don't
' already exist now. There are no changes that affect Timberline Road or the downstream
properties caused by the development of this property as far as off stream flows from the West
over Timberline Road.
' The runoff that is shown on the "City" Spring Creek Master Drainage Plan that flow "our
direction" is also temporary. The design and construction to Timberline will eliminate this runoff
across our site. I think the road will be completed within 10 years. Secondly, the reason this
runoff is shown here is an impass at the Spring Creek/Railroad underpass. This is also proposed
' for construction by your department but I don't know the time frame. This would also eliminate
runoff to our site.
' EROSION CONTROL:
The site is in the high rainfall erodibility zone and in the moderate wind erodibility zone.
The size will be developed in two phases. Part of Lot I is Phase 1 along with the access road,
which is in Lot 2 and also the detention pond. The extended detention will also be constructed
with the pond. A straw bake dike will be constructed around the area inlet. Also a silt fence will
' be constructed along the East property line and remain in place until all construction is
completed.
' The historic and developed calculations are included herein. The report and design of the
drainage system are in compliance with the City of Fort Collins Storm Drainage Design and
Criteria.
' The erosion control required escrow amount is $1,591.65.
' If you have any questions or need any more information regarding this project or report
please let me know.
CENTS "1W fin Np mt dnc
1
STEWART&406SOCIATES
Consulting Engineers and Surveyors
' January 3, 2003
' Stonnwater Utility
City of Fort Collins
P.O. Box 580
Fort Collins, CO 80522-0580
' Dear Basil,
The following is the cost estimate for the erosion control measures for Centerpoint Plaza.
I . CONSTRUCTION COSTS
' 300 LF Silt Fence @ $3/ft $ 900.00
Straw Bake Dike $ 100.00
' Total Construction Cost Estimate $ 1,000.00
2. RESEEDING COSTS
' Reseeding -- 1.62 acres rd $655/acre $ 1,061.10
3. ESCROW REQUIED FOR SITE
' 1.5 x 1061.10 $ 1,591.65
If you have any questions or need more information regarding this estimate please let me
know.
Sincerely,
w:a[ietrn;sr
_ i n
' Franklin D. Bla e, PrE.
FDB/meh (PIA
1
James H. Stewart and Associates, Inc.
' CENfERPOINTcolt atdoc 103 S. Meldrum Street • P.O. Box 429 • Ft. Collins, CO 80522
970/482-9331 • Fax 970/482-9382
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STEWART&ASSOCIATES
Consulting Engineers and Surveyors
103 S. MELDRUM, FORT COLLINS, CO 80521
PH. 482-9331 FAX 482-9382
By: �'a w Date: /" /"Ay Client: / CAa�Sheet No. -Lof
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13 762.0 = REQ. VOLUME
CUMMULATIV! THIGH WATER
VOLUME cu.ft. LINE ft.
CONTOUR
ft.
GE AGE AREA
AVERA
s .ft.
INTERVAL
VOLUME cu.ft.
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14,584.0
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NOTES: 1. F'UH I Ht hIH.S IVU�V I V UI"1 V VLumc „tivrvw annrc ••nv n.+��•.
VOL. = 1/3 (AREA ABOVE) (DIFFERENCE IN COUNTOUR ELEV.)
2. FOR THE REMAIMDER OF THE VOLUMES BETWEEN CONTOURS (SECTION 9.2)
VOL. = DEPTH/3 (A +(AB) - .5 + B) FOR: Uniform Sides sec.(9.2)
3. HWL= (VOL.REQ. -VOL.LOW CUML)*3/(AREA LOW+AREA HIGH+(low area high area)".5)
9.61 = HWL POND j
ORIFICE SIZING
nRIGINAI DESIGN DATA
0.61 = Allowable Des. Release Rate cfs
8.50 = Flowline Orifice Elevation ft
0.65 = Orifice Coefficient Cd
1.11 = Available Driving Head ft
VERT. CIRCULAR PLATE
17.54 = Outlet Area(sq. inches)
2.36 = Circularradius inches
0.91 = Actual Hydraulic Driving Head ft
VERT. SQUARE PLATE
17.34 = ut et Areas . inc es
4.16 = Side for S . O enin inches
0.94 = Actual Hydraulic Driving Head ft
NOTE: 1. VERT. PLATES WILL BE PLACED
AT PIPE FLOWLINE
EMERGENCY SPILLWAY DESIGN
Weir Equation Q = C L (H) ^ 3/2
Q (cfs), C (weir coefficient), L (crest length, feet), H (energy head, feet)
25 = Weir Length L in feet
3.1 = Weir Coefficient
Weir Shape Broadcrested
Design Flow 12.74 (cfs)
Depth of
flow ft
Flow Over Weir
(cfs)
0.10
2.45
0.15
4.50
0.16
4.96
0.17
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0.18
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0.19
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STEWART&ASSOCIATES
Consulting Engineers and Surveyors
103 S. MELDRUM, FORT COLLINS, CO 80521
PH. 482-9331 FAX 482-9382
By: Date: Client: _�7/�/2 Sheet No. Z of
Project:
Subject:
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Consulting En3ineers and Surveyors
103 S. MELDRUM, FORT COLLINS, CO 80521
PH. 482-9331 FAX 482-9382
By: Date: O Client: �c�/mod Sheet No. _';� of
Project: �e✓! DO/iJ r /� ��� 2 J
Subject:
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EMERGENCY SPILLWAY DESIGN
Weir Equation Q = C L (H) ^ 3/2
Q (cfs), C (weir coefficient), L (crest length, feet), H (energy head, feet)
370 = Weirengt Lh L in feet
3.1 =Weir Coefficient
Weir Shape Broadcrested
Design Flow 417 (cfs)
Depth of
flow ff
Flow Over Weir
cfs)
0.10
36.27
0.15
66.63
0.20
102.59
0.25
143.38
0.30
188.47
0.35
237.50
0.40
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0.45
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EMERGENCY SPILLWAY DESIGN
TIMBERLINE OVERTOPPING
Weir Equation Q = C L (H) ^ 3/2
Q (cfs), C (weir coefficient), L (crest length, feet), H (energy head, feet)
410 = Weir Length L in feet
3.1 = Weir Coefficient
Weir Shape Broadcrested
Design Flow 417 (cfs)
Depth of
flow (ft)
Flow Over Weir
(cfs
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0.20
113.68
0.30
208.85
0.35
263.18
0.40
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0.45
383.68
0.47
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0.48
422.68
0.49
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0.50
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DRAINAGE CRITERIA MANUAL
RUNOFF
50
MA
f- 20
z
w
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2
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IL 10
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0 5
to
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11-III"I
MR
ME
.2 .3 •5 1 1, 2 3 5 10 20
VELOCITY IN FEET PER SECOND
FIGURE 3-2. ESTIMATE OF AVERAGE FLOW VELOCITY FOR
USE WITH THE RATIONAL FORMULA.
*MOST FREQUENTLY OCCURRING "UNDEVELOPED"
LAND SURFACES IN THE DENVER REGION.
REFERENCE: "Urban Hydrology For Small Watersheds" Technical
Release No. 55, USDA, SCS Jan. 1975.
5 -1-84
URBAN DRAINAGE & FLOOD CONTROL DISTRICT
No Text
1
1
1
1
City of Fort Collins
Rainfall Intensity -Duration -Frequency Table
for using the Rational Method
(31 minutes - 60 minutes)
Figure 3-1 b
Duration
(minutes)
2-year
Intensity
in/hr
10-year
Intensity
in/hr
100-year
Intensity
in/hr
31.00
1.27
2.16
4.42
32.00
1.24
2.12
4.33
33.00
1.22
2.08
4.24
34.00
1.19
2.04
4.16
35.00
1.17
2.00
4.08
36.00
1.15
1.96
4.01
37.00
1.13
1.93
3.93
38.00
1.11
1.89
3.87
39.00
1.09
1.86
3.80
40.00
1.07
1.83
3.74
41.00
1.05
1.80
3.68
42.00
1.04
1.77
3.62
43.00
1.02
1.74
3.56
44.00
1.01
1.72
3.51
45.00
0.99
1.69
3.46
46.00
0.98
1.67
3.41
47.00
0.96
1.64
3.36
48.00
0.95
1.62
3.31
49.00
0.94
1.60
3.27
50.00
0.92
1.58
3.23
51.00
0.91
1.56
3.18
52.00
0.90
1.54
3.14
53.00
0.89
1.52
3.10
54.00
0.88
1.50
3.07
55.00
0.87
1.48
3.03
56.00
0.86
1.47
2.99
57.00
0.85
1.45
2.96
58.00
0.84
1.43
2.92
59.00
0.83
1.42
2.89
60.00
0.82
1.40
2.86
I
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1
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11
1
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1
1
L
City of Fort Collins
Rainfall Intensity -Duration -Frequency Table
for using the Rational Method
(5 minutes - 30 minutes)
Figure 3-1a
Duration
(minutes)
2-year
Intensity
in/hr
10-year
Intensity
in/hr
100-year
Intensity
in/hr
5.00
2.85
4.87
9.95
6.00
2.67
4.56
9.31
7.00
2.52
4.31
8.80
8.00
2.40
4.10
8.38
9.00
2.30
3.93
8.03
10.00
2.21
3.78
7.72
11.00
2.13
3.63
7.42
12.00
2.05
3.50
7.16
13.00
1.98
3.39
6.92
14.00
1.92
3.29
6.71
15.00
1.87
3.19
6.52
16.00
1.81
3.08
6.30
17.00
1.75
2.99
6.10
18.00
1.70
2.90
5.92
19.00
1.65
2.82
5.75
20.00
1.61
2.74
5.60
21.00
1.56
2.67
5.46
22.00
1.53
2.61
5.32
23.00
1.49
2.55
5.20
24.00
1.46
2.49
5.09
25.00
1.43
2.44
4.98
26.00
1.40
2.39
4.87
27.00
1.37
2.34
4.78
28.00
1.34
2.29
4.69
29.00
1.32
2.25
4.60
30.00 1
1.30
2.21
4.52
1
' ! ` CUP! TRUCTION SEQUENCE
PROJECT: C��'/77�/0(�//�T z,7 STANDARD FORM
QUE.ICE. FOR :W�ONLY COMPLETED BY:
�G/ DATE: %
�dicate by use of a bar line or sxAnbols when erosion control measures will be installed.
jor modifications to an approved schedule may require submitting a new schedule for
approval by the City Engineer.
' YEAR I
MONTH-
SI -- I
----------------
____
�ERLOT GRADING
I
WIND EROSION CONTROL I
'Soil Roughing
Perimeter Barrier
Additional Barriers
'Vegetative Methods
Soil Sealant
Other
tFALL EROSION CONTROL
'STRUCTURAL:
Sediment Trap/Basin
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
tTemporary Seed Planting
Sod Installation
Nettings/Mats/Blankets
Other
--------------------------------+
UTURES: INSTALLED BY
f TATION/MULCHING
CONTRACTOR
SUBMITTED
ISF-C:1989
MAINTAINED BY
APPROVED BY CITY OF FORT COLLINS ON
151C�, I tiI-L)
1--r-T---- T---- T----
RAINFALL PERFORMANCE STANDARD EVALUATION
------- ------
IPROJECT: CC.v
COMPLETED BY:
--------------
DEVELOPEDIERODI
SUBBASIN I ZO
-------------------------------------------------------
>EQ PDivT pl-AZA STANDARD FORM A
K•A.2 DATE:
-------------------------------------------------------
BILITYI Asb I Lsb I Ssb I Lb I Sb I PS
NE----I_(ac)--I (ft) I (A) ((feet) I (a) I (e)
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WN
---------------------------------------------------------------------I
DI/SF-A:1989
WN
---------------------------------------------------------------------I
DI/SF-A:1989
EFFECTIVENESS CALCULATIONS
PROJECT: C.e.jTaFP0,,,, pLAzq
COMPLETED BY: te. A .le
Erosion Control
Method
SARC SOIL-
Ic—D/rgEUT 0, 1Y'tl
A p"AC'7f ro.,c.
Dry LAuD GRASS
SILT Fe&)eG
STIEAIJ BA,ES
IBASIN 1 (1)
BASIN (Ac)
C-Factor
Value
/•00
J. 00
0.01
O.G7
/, 00
1.00
P-Factor
Value
CALCULATIONS
DATE: q '„
Co=ent
3, 14 A
C= (/'00XF-ZI)+(0.O-7x'.:c-�
7,00
Z'67-I-- 0.0119+0.Z19B _Z•9017
-7.00 — 7•ov =
0,5e) X 0.50 = 0. 4-D
6.4IS- X 6.40)] X /DO
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RaSF"EC D
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asstii„ri"k `V •a u_,a',-"� .., it .1aq {5 "-
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e`� \ LEGEND
a ' III as t Va R567 HEC—RAS CROSS SECTION
Ii.
Ch asso BASE FLOOD ELEVATION
PONOID WS L '1� ! _ __-- 1/2—FOOT FLOODWAY BOUNDARY
491:E.8 FT, GVD
100—YR FLOODPLAIN BOUNDARY
FLOW PATH DIVIDE
r
AREAS OF FLOODING DETERMI
NED
BY APPROXIMATE METHODS
' _ .. III III �1 II • _
i"
p
f
• ,4' 1T A _r." N lfi a n\_ g •\\ 9"f [5i'. } '� �,J
RTVi COFCI) TAW/MRC "
IQ2 SCALE 1' = 200• ,na,�, ,�,p„ 100-YEAR FLOODPLAIN/FLOODWAY MAP
t"4 N MdBeonCorsul E a I CITY OF FORT COLLINS FULLY -DEVELOPED CONDITION WITH as 3
aTva CONTOUR INTERVAL = 2 FT RRoroBA sc.owc BLV/OCS }�}�4 "WI "�
CiWa'a\cRmvw 6mwanm}d SPRING CREEK MASTER DRAINAGE PLAN EXISTING FACILITIES
afV6 OI/IA/2003 GJK amaaua•r�mgawaV
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t ..MIDPOINT DRIVEED,—
No construction in Ombedine I r= r - - - - _
Road at this time. This project will
require deposit escrow for their i -`1?M1 — - CIENCiMUTE MI10
shore of road development
,-
w0t
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LEGEND aft' .'., ',, b f DI ___
^ w'BNNI AN
RE
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095
AUD
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AND
RE
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t ,x, •,xxLN 605 halt c rt'- p p
CCIRCIRI
0.1UIRRICIIII
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DRAINSAI 0
i = _ _ < _ _ 8,5 Y R 0401V
49'
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09.61
wl
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SN/
0+00 0+15
SPILLWAY PROFILE mm 0
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SCALE. I" - 40'
a
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rg,\A ,
.' I i Existing 1 Story
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IN : 7% FINISH FLOOR 11.76
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STORM DRAIN PROFILE
HORIZ. 1 "w 50' VERT. I" = 5'
0+00 0+50 1+00
ADRRHII
NAMDC FF= 14.6
NOW lswur Drew 1 e-$ DEVELOPED SWALE WITH PHASE 7 GRADING
142, '' _--1--r---- 1----------,i__I-- D= 104. CIDS fNORTH
BEFORE SACKING ONTO 77MBERINE
1---i-ar _t__
99/e 1 { Il0RTH IN EXISTING SWALE
9 fnslxc ylwlc umH• 00 95. 19 CFS FLOW/Ng NORTH
¢s' BEFQRE OVERFLOWING AND GOING E45T
EXISTING SWALE EAST SIDE TIMBERLINE
SECTION A — A
NTS
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Of pR
IPSS�A�S
PROJECTS.
RIAI 15 A
NOTE.'
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DETENTION POND FACIU77ES SHOWN ARE FOR PHASE 1 ONLY.
N>
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THIS PROJECT IS CONSIDERED TO BE ONE BASIN ONLY.
w
77MBERLINE ROAD /S NOT BEING DESIGNED WITH THIS PROJECT.
IY
THEREFOR THE BASIN LINE /S THE SUBDJNSION BOUNDARY LINE
z
O
SEE SHEET 8 FOR CRY GRAD/NC AND EROSION CONTROL NOTES
O
RESEEDING CALCULATIONS ARE FOR DISTURBED AREAS
CAUSED BY CONSTRUCDON WHICH ARE NOT TO BE LANDSCAPED
c
AT THAT PHASE OR USED IN THE DETENTION MIND AREA.
w
ALL DISTURBED AREAS NOT IMMEDM TELY LANDSCAPED -
e
--
p
MUST BE RESEEDED AND MULCHED
d
THE DETENTION POND AREA IS TO BE USED AS A SEDIMENT
9
TRAP DURING CONSTRUCTION B1' INSTALLING A GRAVEL FILTER
AROUND THE OUTLET STRUCTURE
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BASIN DATA: SITE AREA 70 ACRES
^
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HISTORIC 0 2 AN2.64 ICES
V ' onLD
HISTORIC 0 10 - 4.50 CFS
Q
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HISTORIC 0 100 = 13. 15 ICES TOTAL S17E
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DEVELOPED 0 2 - 772 CFS
l^�]�J
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' v
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DEVELOPED 0 100 = J6.06 CFS
W
rc
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RELEASE RATE 2.64 CFS
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PHASE I SITE AREA 1.62 ACRES
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DEVELOPED 0 1 = 7.72 CES
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DEVELOPED 0 /0 AIRIJ. 19 CFS PHASE 1
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DEVELOPED 0 100 AD:J605 CFS
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RELEASE RATE 0.61 CFS
9
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4SRNO I
FOR
DRAINAGE OURET
`RIPIIVE (15E EASEMENT
APPROVED FOR CONSTRUCTION AS
SHOWN ON THIS SHEET FOR GRADING AND = 2
STORM SEWER /N THE too FOOT R
PUTTE RIVER POWER AUTHERRY EASEMENT
> Q oO
BY'�w..7�C...•..,r� a W 2
W
U W Pi 3i r"
DATE•—Df � y DEC,
2 ci
0
wo LEA
City of
Fart Collins, Colorado
LTTIUTI' PLAN APPROVAL
APPROVED:
CRy Eyimm,
Dar,
CHECKED BY..
wA« a Iw t,"t,r DRAY
a,r.
CHECKED BY.'
VERDI Ittnirr
Len
CHECKED BY..
va* A n rya n,
CHECKED BY..
imMie fpinw
Mls
CHECKED BY.-
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