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• Reshanau Lake Management Plan The plan proposes a goal that can be measured in quantitative terms such as a "Tropical State Index (TSI). The TSI is a measurement used by lake managers to describe a condition of a lake based on three variables: Total Phosphorus, {(TP), nutrient concentration) }, Secchi Transparency {(SD), water clarity) }, and Chlorophyll -a {(CHLA), algae concentration) }.This measurement was quantified during the 1995 study and was determined to be "68." The MPCA (1990) classifies lakes based on TSI into the following categories, 1) lakes which fully support swimming, 2) lakes which partially support swimming, and 3) lakes which are non - supporting of swimming. The 1995 measurement for Reshanau Lake of "68" categorizes the lake as a "lake which is non - supporting of swimming." Assuming that no more recent data exists, and that quality of the lake has probably not improved and likely decreased since the 1995 study, we propose establishing a summertime TSI rating of less than 57.This would correspond to a TP concentration of 60 ppb, SD of >/= 1.2 m, and a CHLA concentration of < 25 ppb. Achieving a growing season average TSI of 62 or less would characterize the lake as partially supporting swimming. Both the duration and frequency of algal blooms would be reduced to less than 25% of the summer. We would like to achieve this goal by 2008. • The following activities were considered to varying degrees during the last six months: Harvest rough fish Harvest curly leaf pondweed Obtain benchmark data Controlling the migration of rough fish from other lakes Chemical treatments to try eradication of curly leaf pondweed Shoreline restoration Controlling lake elevations Communication and education Street and storm sewer issues All of the above management practices alone will not significantly change the water quality of the lake. A combination of management strategies will need to be implemented over a period of time to achieve the desired results. It was decided to focus on those activities we perceive to provide the greatest potential for a positive impact on the lake and the surrounding watershed. And, begin a more comprehensive program of monitoring the Lake and input sources to identify areas to focus on in the future. The specific strategies of the Plan are as follows: G: \Admin \Board \Agenda Paks \2005 Agenda Paks \2005 -04 -13 \Reshanau mgmt plan.doc6