08-20-1997 - Laserfiche WebLink

Home Browse Search

��- ��• 1.%J. J.'t• rAA oic 4au LiaU 5EH 002 • ,sei • MEMORANDUM ■ST.PAUL,MN ❑MINNEAPOLIS, MN C Sr CLOUD, MN C CHIPPEWA FALLS,WI C MADISON, WI C LAKE COUNTY,IN TO: Jim Ericson, City of Mounds View FROM: Rocky J. Keehn ‘ DATE: August 8, 1997 RE: Silverview Estates, City Planning Case 495-97, SEH File No. AMOUND9701.00 Our review was based on a set of plans received by the City on July 25, 1997. The preliminary grading and erosion control plan was dated 7/11/97. One item not submitted was a drainage map showing the subwatersheds to each pond. The map should include roof drainage and show those areas that will flow to the garage and thus need to be drained using pumps (show where the pump runoff will discharge). Based on this set of plans,the major pond in the center of the site appears to be adequate. The other two ponds need further refinement. The minimum depth of a NURP ponds is four feet. The proposed pond next to the 1 story office building does not meet this criteria. The pond located next to Silver Lake Road has no separation between the inlet and the outlet on the south side of the pond.. This will cause short circuiting and thus greatly reduce the efficiency ill of the pond. The site also greatly infringes on the 100-foot buffer around the wetland. Although some measure have been done to protect the wetland, there are several highly used impervious surface next to the wetland. To help this problem at the 1 story office building parking lot,we would like the developer to investigate if they can move the building 10 feet further northwest. This will create two additional parking stalls which allows them to eliminate the two parking areas closest to the wetland. The City should also consider obtaining a 20 foot easement around the delineated wetland.. By obtaining the easement, the City can control land use (mowing, etc) in the reduced buffer. We would also recommend that plantings be used in the easement which deter people from going into the area. We noticed that on one drawing the central pond has a walkway on the wetland side. The problem with this is that the grading plan shows a riprap overflow in the same location. The developer should correct this inconsistency in the plane. In order to complete our final review,the developer should submit the following: 1. Drainage Map showing the proposed subwatersheds to each pond and parking garage. 2. Address the feasibility of changing the parking lot of the 1 story office building to reduce the impact on the wetland buffer. 3. Address the feasibility of providing a 20 foot easement around the wetland so the City has control of the buffer. 4. Revise the grading and drainage plans so the 1 story office building pond has four feet of depth and the senior housing pond will not short circuit. If you have any questions or if I may be of further service please call me at 490-2026. RJK/rjk