HomeMy WebLinkAbout2001-08-23 BRAA Email Re Drainage-Pond Calculations:: n1eIson
Postler, Dennis M [dpostler a@bonestroo. com]
, st: Thursday, August 23, 2691 2:15 PM
�: Jay Johnson �E- mail); Kimberly Kamper (E-mail)
EC: Kris Danielson (E- mail); Mark Vierling (E- mail); S cott Richards (E -mail)
Subject: Sigstad Carpets -- Drainage /Pond Calculations
I have had a chance to review the drainage calculations and pond sizing for
Sigstad's and talked A to the engineer at Otto Associates would prepared them,
In short, the drainage calculations, pond sizing and proposed stormwater
runoff for the developed conditions are acceptable as submitted.
A "brief' explanation:
The existing site conditions have slightly over half of the site draining to
the north /northeast to the southerly ditch of 60th Street North, which then
drains easterly. Slightly less than half of the site drains to an existing
swale to the southeast corner of the site, then easterly. Drainage from
both directions eventually ends up at the lowpoint in the southwest corner
of 69th St. N. and Oakgreen Avenue.
The proposed site conditions take almost all of the storm water runoff from
the site to a pond in the southeast corner of the property. Although half
of the site that used to drain northeasterly is now redirected to the
southeast, the pond retains the runoff under various sized storm events and
discharges approximately the same rate of runoff to the southeast that the
existing site conditions do. Overall, the developed site is discharging at
a rate less than the existing site conditions. And when we use the term
"redirected ", this flow is tributary to the same ultimate ponding area, so
the developed scenario is actually better than the existing conditions, in
firms of rate control.
Dennis M. Postler
Eonestroo, Rosene, Anderlik & Associates
2335 West Highway 36, St. Paul, MN 55113
Direct: (651) 694 --4815
Office: (651) 636 -4666, x4815
Fax: (651) 635 -1311
Cellular: (612) 865.9187
E -mail: dpostler@bonestroo.com
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