Laserfiche WebLink
CMP Part 3A. Environmental Protection Plan <br /> The Metropolitan Council's Storm Water Impact Investigation (1973) <br /> included several pertinent conclusions, as follows: <br /> 1. The total quantity of storm water runoff will increase if present urban <br /> development practices are continued. <br /> 2. The impact of converting an area of undeveloped land to dense <br /> residential use will increase the pollution load from that area by more <br /> than ten (10) times. <br /> 3. The storm water from dense residential areas averages fourteen times <br /> greater phosphorus concentrations than the lakes, based on the results of <br /> � this study, other similar studies in Minnesota, and that found in literature. <br /> These concentrations are over nine times greater than the concentrations <br /> associated with nuisance algae blooms. <br /> 4. Storm water runoff accounts for almost all of the nitrogen and <br /> phosphorus added to the lakes and streams. This conclusion is based on <br /> average flows and quality of the effluents from sewage treatment plants <br /> compared to the flows and quality of the storm water runoff. <br /> Based on this data and the previous published studies, the Storm Water Study <br /> included the following recommendations: <br /> L The objectives of storm drainage design should be revised from rapid <br /> disposal to concepts which will decrease the impact of storm water by <br /> reducing peak flows and improving quality. <br /> 2. The design criteria should include concepts such as on-site disposal, <br /> retention ponds, retention of recharge areas and marshes, grass waterways, <br /> and other new methods of management of storm water which may decrease <br /> capital requirement for new development. <br /> The following storm water policies and guidelines were then recommended for <br /> consideration and adoption by the Metropolitan Council. These guidelines <br /> applied to the development of municipal and private drainage plans and storm <br /> water drainage systems including additions to existing facilities, and particularly <br /> applied to Orono in its endeavor to protect and preserve Lake Minnetonka: <br /> a. The systems shall be compatible with metropolitan and local flood <br /> control plans. <br /> b. Storm water drainage shall be discharged to marshlands, swamps, <br /> retention basins or other treatment facilities priar to entering the public <br /> waters <br /> City of Orono Community Management Plan 2008-2030 Page 3A-21 <br />