HomeMy WebLinkAboutSite Certifications - 12/21/2001 (2)STEWARr&ASSOCIATES
Consulting Engineers and Surveyors
December 19, 2001
Mr. Jay Barber
Stormwater Utility
City of Fort -Collins
P.O. Box 580
Fort Collins, CO 80522-0580
Dear Jay,
r/'65dVOi T nJ4S 11-;0J V'` 4
RE: MIDPOINT SELF -STORAGE SOLUTION FACILITY
I have inspected the "AS BUILT" construction of the storm drainage facilities and surveyed the
elevations of the curbs, flow lines and detention ponding areas.
The storm drainage facilities, including the proper sized restricted outlet openings, have all been
installed according to the approved plans.
There were some changes made during construction. The pan grades were changed to keep .
water away from the building entrance.
The revisions made will not adversely affect storm drainage.
The detention ponds have been graded per the plans and will provide the required volumes of
ponding.
The landscapers will seed in the spring.
I have attached a print of the grading plan, on which the surveyed "AS BUILT" elevations and
pond calculations are shown.
Please call if you have any questions regarding this project.
Sincerely,
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Franklin D.
FDB/meh
James H. Stewart and Associates, Inc.
103 S. Meldrum Street • P.O. Box 429 • Ft. Collins, CO 80522
970/482-9331 • Fax 970/482-9382
AS BUILT DETENTION POND HIGH WATER LINE
MIDPOINT STORAGE SOLUTIONS POND ° A °
REQ.= 0.05 ACFT
2 178 Q REQ. VOLUME::
CONTOUR AREA AVERAGE AREA INTERVAL CUMMULATIVE HIGH WATER
(sq.ft.) (sq.ft.) VOLUME (cu.ft.) VOLUME (cu.ft.) LINE (ft.)
88.41 0.0
1 89.01 1,407.01 1 1 1 0.01
1 90.01 2,288.01 1 1 1 90.01
90.51 3,027.0
NOTES: 1. FOR THE FIRST CONTOUR VOLUME A CONIC SHAPE WAS ASSUMED
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)
n
AS BUILT DETENTION POND HIGH WATER LINE
MIDPOINT STORAGE SOLUTIONS POND " B "
REQ.= 6.06 ACFT
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)
IV
SCALE 1" IN
50'
M/pPOINT DR/VE—
I
LEGEND
—I- Ed,
PIECE SPECIVICE
X,
,
N11111" "rip
CIIIII,; MCI
SEW PEW WIrro
Wass SEW
Y7 All
d,
POND 'A"
A TRIBUTARY AREA'S IMPI RVIOUSNESS RA DO 10 = 90x
i=0.9
B. CONTRIBUTING WATERS ED AREANESS RA TO A Now 1.36 ACRES
C. WATER OUALITY CAPTUF E VOLUMEESS RATIO WOW = 0.40 WATERSHED INCHES
D. DESIGN Ll7LUMEY CAPT IRE VOLUMEESS RATIO VOL. = 0.05 AC —FT
E. AS —BUILT VOLUME VOL. = 0.08 AC —FT
POND 'IB"
A TRIBUTARY AREA'S IMPI RV 0USNESS RATIO 10 = BOX
i PEN 0.8
B. CONTRIBUTING WATERS EO AREANESS RATIO A = 1.76 ACRES
VOLUMEESSC. WATER DUALITY CMETUAE D. DESIGN VOLUMEY CAP REE VOLUMEESS A AHWATERSHED INCHES
O VOL, = 0.06 AC FT
E. AS —BUILT VOLUME VOL. = 0.06 AC —FT
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