07-22-1985 Council Packet - Laserfiche WebLink

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Zoning File #852 July 19, 1985 Page 2 I have enclosed the report from Glenn, Cook (Exhibit C included in Council packets and discussed at your last meeting) that outlines the issues that must be addressed in each land alteration application. We have no performance standards to offer except for the Nutrient Quality Analysis (Exhibit I) submitted by the applicant's engineer based on standards established by the Rice Creek Watershed District (Exhibit J). The M.C.W.D. has suggested that we consider the use of these standards when matters of water quality are in question. In review of that analysis, it would appear there will be no change in the nutrient loading and assimilative capacities of both pond areas as a result of the alteration. Before I respond to each issue and comment on the reports of the various reviewing bodies, I would like to bring you up to date with the preliminary facts about the proposal. The formal or decorative pond (80' x 801) will be constructed within a low area covering approximately 3/4 of an acre in area below the OHM of Lake Minnetonka at 929.4. The southern portion of the pond is protected by a conservation and f lowage easement. At the time of the Gregory/Duff lot line rearrangement, the subject area functioned as both a retention area for the localized watershed of 2 to 3 acres and as an overflow area for wildlife pond to north. When the Gregorys constructed the new access road, the overflow to the south was in- hibited - culvert was placed only at intersection with County Road 15 to not hinder flow of drainage in County Road ditch area. The old driveway bed was removed changing the elevations along the roadway portions of the property and drainage now flows from retention area out to lake via southern culvert (see Exhibit K grading map). The plan shows the decorative pond receiving runoff from a water- shed of 2.6 to 3 acres. The pond will drain north to the wildlife pond and out via the most northern culvert. A proposed outlet channel will allow vegetation to become established and act as a filter for water flowing into the wildlife pond. The pond will be aerated by a fountain to reduce algae growth and maintain good water quality. Dr. Hanson says that the aereation of this pond is crucial. Planning Commission wants the applicant to specify the type of pump to be used. Berming must be done between decorative pond and ditch along County Road 15 so that drainage no longer flows through southern culvert but into channel - wildlife pond - through skimmer and northern culvert to Lake Minnetonka. A total of 3000 cubic yards of earth will be al- tered. 1800 cubic yards excavated for pond area and 1200 cubic yards to be altered in reshaping the upland slope to the west and berminq along County Road 15.