07-22-1991 Council Packet - Laserfiche WebLink

Home Browse Search

8. phosphorus) and pesticides within at Icxst the l,000-fc>->t shoreland management districts of Lake Minnetonka. The MCWD should work with the cities, county extension offices and other cooperating agencies to develop a comprehensive program of public education on fertilizers and chemicals (what types to buy and prop>er use), the need for ground cover to prevent erosion, proper cutting and control of lawns, leaves and other vegetative matter, and the licensing of commercial applicators. Minimize the pollutants reaching Lake Minnet leachate and residues from past treatment prac d its tributaries via septic tank Lead Agency: Cities Cooperating Agencies: MWCC. MCNVT). MPCA DNR, Council In the late 1960s, the Metrof>oIitan Sewer Board (now the Metropolitan Waste Control Commission) was organized. One of the reasons that it was created was tc '-'al with the pollution of Lake Minnetonka caused in part municipal wastewater treatrr '.ans. The decision was made to phase-out all of the "municipar treatment plants on the L .^nd convey the sanitary sewage via metropolitan interceptor sewers to new state-of-the-art metropolitan wastewater treatment plants off the lake. That plan was carried out and as a result, the water quality in Lake Minnetonka improved dramatically. Another part of problem has not yet been fully addressed...on-s:te septic systems. Properly designed and operating on-site systems, like the municipal wastewater treatments plants on Lake Minnetonka, do treat the wastes and improve the quality of the effluent Like the former municipal plants, they arc much better than allowing sewage to flow into the lake untreated; but, they are not the best way to deal with sanitary sewage in the Lake Minnetonka watershed. The water quality assessment identified in policy # 1 should identify not only the types but sources of pollutants in the lake. It is expected that non-point sources will prove to be the biggest contributor of pollutants, but on-site systems arc also expected to be a source of contamination. Residues from past in-iake dumping of sewage treatment effluent and concentrations of phosphorus in bottom sediments fro: i a wide variety of sources, are also likely to contribute to the existing water quality probleitis in the lake. The cities should concentrate their efforts on dealing with on-site systems located within the 1,000-foot shoreland protection zone of the lake and its wetlands, and within the floodplain of its tributaries; with programs expanded tu include entire cities by the end of 1992. City programs for managing on-site systems (including private larger-scate treatment systems should include: mapping the location of each parcel seived by an on-site system within the shoreland zone; annual inspections of each on-sHe system by a state-certified inspector; reporting of problems and corrective measures nroposed/taken to the city, record-keeping by the city; annual reporting by the city to the MWCC or other appropriate agency for distribution to interested parties including the LMCD’s Water Quality advisory committee. The exact extent to which residues in the lake contribute to water quality problems should be determined as part of the initial assessment, and a program developed to address the problem if it is determined to be significant 7/il Draft - 12