1994-07-08 Storm Water Calculations
MEYER-ROHLIN, INC.
ENGINEERS-LAND SURVEYORS 1111 Hwy. 25 N., Buffalo, Minn. 55313 Phone 612-682-1781
July 8, 1994
Mr. Bob Robertson
R.C.M.
10901 Red Circle Drive
Minnetonka, MN 55343
RE: Psyks 6th Addition
Albertville, Minnesota
Dear Bob;
Enclosed are the storm water calculations, a possible future
storm sewer location and estimates of cost for this storm sewer
for the cost sharing as has been proposed for the psyk 6th
Addition.
As per the attached psyk concept plan, we show 7.39 acres of the
psyk property draining to the northeast, of which 4.54
encompasses the 6th Addition. The balance of the 2.85 acres will
be future additions to the west.
We also show 5.84 acres of the Marx property currently draining
into the cornmon low area adj acent to the psyk Addition. No
preliminary plat or grading plan has been submitted to date for
the Marx property; however, as the land is developed with
streets, etc., it would appear that a much greater area than the
5.84 acres will be serviced by the proposed storm sewer.
Conservati vely, we are using an 8.0 acre area from the Marx
property in calculating the storm water runoff. The attached
calculation sheets are based upon 7.39 acres of psyk property
and 8.0 acres of Marx property being serviced by the proposed
storm sewer. Based on the assumption that the Marx property
would develop as the psyk property (1/3 acre lots), we calculate
a peak flow for the 5-year storm event for storm sewer design to
be 11.96 cfs. A 21" storm sewer at 0.5% grade is sized for this
peak flow.
The cost estimate for this storm sewer, based upon the sketch
plan enclosed, is:
21" RCP (under streets)
21" Dual-wall PE pipe
Catch basin/manhole
Sedimentation pond with
outlet control, skirrmer etc.
72 If @ 25.00/1f =
300 If @ 22.00/1f =
5 each @ 1000/ea =
1,800
6,600
5,000
1 Is @ 5000/1s =
5,000
Thore P. Meyer, Professional Engineer ,l1obert Roh!in, Licensed Land Surveyor
$18,400
J!11
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page 2
Mr. Bob Robertson, R.C.M.
The contributing areas in this proposal are approximately the
same, resulting in a 50%-50% cost sharing. Obviously, as the
Marx property develops, at the time of the storm sewer
installation, the drainage area from the Marx property could be
substantially increased, increasing the pipe size and costs, and
hence increasing their proportionate cost sharing. We feel,
however, this proposal is a realistic approach at this time.
If you have any questions, please feel free to contact me.
Respectfully submitted,
cc: Mike Couri
Doug psyk
File 94120