HomeMy WebLinkAboutSite Certifications - 05/27/2010April 12, 2010
Mr. Jay Barber
City of Fort Collins Stormwater
700 Wood Street
Fort Collins, Colorado
RE: Drainage Certification
Poudre Fire Authority Station No. 4
Dear Jay:
Jim
INTERWEST CON S U LT I N G G R O UP
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Please accept this letter and the attached documents as the Drainage Certification for the
above project. Based on the survey provided by King Surveys, a site visit, and
discussions with the contractor, the project is in substantial conformance with the
approved plans and drainage report.
The attached documents show as built elevations for the site including storm sewer pipe,
storm sewer structures, and pond grades as well as calculations for the detention and
water quality pond. The detention pond has been built correctly; however, the water
quality capture volume is slightly larger than the design, but there is still adequate pond
volume to achieve the required detention volume.
Please review this information and give me a call if you have any qudr tions.
Sincerely,
A
Robert Almirall, P.E.
oPPpO REG/,g
v SeO
F
fl 'CC
33441 F'
S70NALE* �
1218 W. ASH, STE. C, WINDSOR, COLORADO 80550
TEL. 970.674.3300 - FAX 970.674.3303
UTILITYAS--RUIL T SUR VEY
DATE:
12/01/09
20 10 0 20 40 60
SCALE IN FEET
LEGEND
a FIRE HYDRANT
O_ STORM MANHOLE
pd WXXR VALVE
Qp SANITARY SEATS MANNCIE
3 SANITARY SEXIER BESIDE
WATER MRS STOP
CO UNDER DRAIN MEAN BUT
0 :ARILAT0N MANHRE
® IRRIGATION VALVE BOX
NDTE:
uD- ELEVAnONS ARE UD ELLVAnONS
'CP. NUP ELEVAnO E ARE OPERATING NUT EL AFONS
STORM INIET BOXES ARE GRAPHIC REPRESENTAnCH
ONLY. NOT ACTUAL SIZE.
I, ROBERT A MESNITZER. A DULY REGISTERED LAND SOHIEYOR A ME
STATE OF CMRtADO. OD HEREBY STATE MAT ME UMUTES SIOAS
HEREON MERE DETERMINED FROM ME RESULTS OF AN ACTUAL
SOLD SURVEY MADE BY ME OR UNDER MY SUPERNSON AND ME
INEORMAVOR SHOWN HERECN IS MUE AND CORRECT TO THE BEST
Of MY BEUEF AND MNPMEDGE,
ROBERT J. MESNIRER FOR AND ON ME BMALIF OF KIND SURVEYORS. INC.
LS SAIIM
VERTICAL DATUM:
BENCHMARK: CITY OF FORT COLLINS VERTICAL BENCHMARK 6-02
ELEVATION-5023.27 (UNADJUSTED 1929 DATUM)
HORIZONTAL DATUM
COLORADO STATE PLANE COORDINATES HAD 83(2007) DATUM.
HORIZONTAL CONTROL BASED VRS.
NOTE,
1. ALL PROPERTY PINS. INTERSECTION MONUMENTS, AND SECTION
CORNERS DISTURBED DURING CONSTRUCTION MUST BE REFERENCED AND
REPLACED UNDER ME SUPERVISION OF A LICENSED SURVEYOR.
2. THIS AUTOCAD ORAWING CONTAINS INFORMATION THAT 15 NOT
VISIBLE ON THE PLOTTED COPY. TO OBTAIN ALL THE INFORMATION THAT
IS AVAILABLE IN THIS DRAWING, ALL ME AUTOCAD LAYERS MUST BE
TURNED ON AND THAWED.
3, THE SIZE, TYPE AND LOCATION OF ALL KNOWN UNDERGROUND
UTILITIES ARE APPROXIMATE WHEN SHOWN ON THESE DRAWINGS. IT
SHALL BE THE RESPONSIBILITY OF THE CONTRACTOR TO VERIFY THE
EXISTENCE OF ALL UNDERGROUND UTILITIES IN ME AREA OF THE WORK
BEFORE COMMENCING NEW CONSTRUCTION. ME CONTRACTOR SHALL BE
RESPONSIBLE FOR LOCATING ALL UNDERGROUND UTILITIES AND SHALL
BE RESPONSIBLE FOR ALL UNKNOWN UNDERGROUND UTILITIES,
6. ALL PROJECT CONTROL LISTED HEREON IS PROVIDED AS A
COURTESY. IT IS ME RESPONSIBILITY OF ME RECIPIENT TO VERIFY ME
ACCURACY OF ME COORDINATES AND ELEVATORS SHOWN PRIOR TO
USING MEN FOR ANY PURPOSES.
For POUDREFIREIVO. 4
FOR_DRAHOTA CONSTRUCTION
STORM MANHOLE
,RIM=5077.8
INV W=5072.55
INV SE=5072.99
I
STORM MANHOLE NV N=5072.72
RIM=5077.0 %
INV E=5071.27
INV SW=5071.19 R ''
soli--` Ilrl
/ STORM INLET'
FL CURB=5075.02
INVERT-5070.28
r '
R 8
r �rrr S r" rfk� OaOn
W,
50�° 18" RCP W/ FES /
ELEV=5070.05
6' PVC PIPE �/1.'`, s°0,0�
ELEV=5068.86 a a
r
r •
r , '
•
r [\ r _ r r
OUTLET STRUCTURE /
TOP GRATE=5069.09 �.
6" PLATE=5067.53
5 1/4" PLATE=5067.51 SO ------
.0 .: 13' -0 LAN -
STAFF GAUGE 5068 - ------- ----------
5
"6AUGE-0=5068.0------------
r ow
-- yoeg 5p65 _
m
DIRT POND SPILLWAY 4" ADS PIP,£
ELEV=5064�.24
ELEV=5070.10 `
506 7-
15" RCP W/ FES
ELEV=5067.32
STORM INLET
FL CURB=50
INVERT-5074
- - 5p65_
__ b
e� w
\ pb
h
E.E.tEV= PIPE
----------' r�LEV5062.91
24
WATER VALVE
LID=5077.4
a OP NUT=5073.3
WATER VALVE
LID=5077.4
OP NUT=5073.5
STORM INLET
FL CURB=5076.09
INVERT=5073.68
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SHEET I OF I
AS BUILT Detention Pond - Stage/Storage
LOCATION:
PFA #4
PROJECT NO:
1094-052-00
COMPUTATIONS BY:
SB
DATE:
4/12/2010
WQ WSEL-
100-yr WSEL-
TOP OF BERM -
V=1/3d(A+B+sgrt(A'B))
where V = volume between contours, ft3
d = depth between contours, ft
A = surface area of contour
WATER QUALITY REQD:
0.06 (Ac-Ft)
DETENTION REQD:
0.26 (Ac-Ft)
TOTAL REQD:
0.32 (Ac-Ft)
Stage
(Elev)
Surface
Area
(Ft^2)
Incremental
Storage
(Ac-ft)
Detention
Storage
(Ac-ft)
Total
Storage
(Ac-ft)
5067.6
0
5068.0
610
0.00
0.00
0.00
5069.0
6602
0.07
0.00
0.07
5069.1
7423
0.02
0.00
0.09
5070.0
14810
0.23
0.23
0.31
5070.1
15248
0.03
0.26
0.35
5071.0
19185
0.35
0.61
0.70
04-10-10 Detention Pond ASB.xIs
Proposed Detention Pond - Stage/Storage
LOCATION: PFA #4
PROJECT NO: 1094-052-00
COMPUTATIONS BY: ES
DATE: 7/20/2009
WQ WSEL-
100-yr WSEL-
TOP OF BERM -
V=1/3d(A+B+sgrt(A'B))
where V = volume between contours, fe
d = depth between contours, ft
A = surface area of contour
WATER QUALITY READ: 0.06 (Ac-Ft)
DETENTION READ: 0.26 (Ac-Ft)
TOTAL READ: 0.32 (Ac-Ft)
Stage
(Elev)
Surface
Area
(Ft^2)
Incremental
Storage
(Ac-ft)
Detention
Storage
(Ac-ft)
Total
Storage
(Ac-ft)
5067.6
0
5068.0
502
0.00
0.00
0.00
5068.9
5748
0.05
0.00
0.06
5069.0
6331
0.01
0.01
0.07
5070.2
14051
0.27
0.29
0.34
5070.5
16623
0.11
0.39
0.45
5071.0
19195
0.21
0.60
0.65
07-20-09 Detention Pond A.xls