05/02/1994 Park Board Packet - Laserfiche WebLink

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WATER QUALITY IMPLEMENTATION STRATEGY SURFACE WATER MANAGEMENT NONPOINT SOURCE POLLUTION TO ALL METROPOLITAN WATERS Summary of The Policy Issue In 1990 the U.S. Environmental Protection Agency (EPA) and the Minnesota Pollution Control Agency (MPCA) agreed on a goal to reduce nonpoint source pollution in the Minnesota River by 40 percent from pre-1980 levels. The two agencies have set 1996 as the target date to achieve this goal. To accomplish this goal, current land development and agricultural practices must be altered to restrict nonpoint source pollutants from entering area water bodies. While the Minnesota River may be an acute case of water quality degradation due to nonpoint source pollution all water bodies in the seven county area are impacted to some degree by human activities in both urban and rural areas. The Mississippi River, especially in the Spring Lake and Lake Pepin area, is severally impacted by excessive algal growth. A major inter-state and federal study is currently being conducted to identify the causes of the excessive algal growth. However, it is known that nutrients, nitrogen and phosphorus, from whatever source are the prime cause of excessive algal growth. Both the State of Wisconsin and the U.S.Environmental Protection Agency are attempting to get the MPCA to impose phosphorus limits on the Metropolitan Plant in St. Paul as a means to reduce the algal growth. If phosphorus limits are imposed on the Metropolitan Plant this could result in capital expenditures of $80 to 360 million. Since phosphorus is found in surface water runoff it may be more cost effective to control nonpoint sources of runoff and have a more beneficial impact on the river than by controlling point sources of phosphorus. To address the acute problems on the Minnesota River, the Council developed an interim strategy for communities in the Minnesota River basin. This strategy incorporated basic water quality management practices that will improve the water quality of the area water bodies. During the public participation process in developing these strategies,it became clear that these same interim strategies were appropriate for all local governments in the seven county area. A consistent and equitable policy is established to apply these strategies metro-wide. The Problem The Metropolitan Council has documented an increase of nonpoint source pollution to area water bodies. These added pollutants reduce the recreational value and accelerate the eutrophication of area water bodies. The increase of nonpoint source pollutants to area water bodies can be traced to two primary sources: land development and agriculture practices. Land development or urbanization,generally increases both the volume of runoff as well as the concentration of pollutants in the runoff. This happens with the conversion of land to hard surfaces and by the destruction of wetlands. Detention ponds or artificial depressions can help mitigate these impacts. The best designed ponds, however,will not reduce the increased volume of runoff following urbanization nor will they totally remove the additional pollutants following urbanization. An increase in runoff volume, total phosphorus and other pollutants are the results of urban development.