08-02-94 CCM - Laserfiche WebLink

Home Browse Search

■ Poor water clarity ■ Odor ■ Litter ■ Level control ■ Fertilizer control As noted in the North St. Paul plan, water level concerns (either too high or too low) received the most attention. The North St. Paul plan proposed that sediment be removed at storm sewer inlets into Silver Lake in 1991. 4.2.1.6 VBWD Water Oualitv Management Goals Silver Lake is identified as a Category I water body in Section 3.2 -- Water Quality Management Plan, based on existing water quality data and its existing and desired recreational uses. A Category I water body fully supports all water -based recreational activities including swimming, scuba diving, and snorkeling. Further description of this classification is included in Section 3.2. Section 3.2 also shows that Silver Lake is to be managed to protect and possibly restore its water quality. Because of its high total phosphorus and somewhat high chlorophyll a concentrations (see Figure _), Section 3.2 also shows Silver Lake as "borderline" in terms of the current and expected use of the lake conflicting with it existing water quality. The lake's watershed is nearly fully developed. Additional nutrient loading due to further development or other land use changes in the watershed is not anticipated. Future watershed management efforts should, therefore, focus on preserving the treatment efficiency of existing runoff detention basins and wetlands throughout the watershed. This focus will ensure that the impacts of runoff from the lake's urbanized watershed are minimized, and that the current water quality of the lake is preserved. VBWD will complete hydrologic and nutrient budgets for Silver Lake, depending on the availability of funds, See Section 3.2 — Water Quality Management Plan for more information about hydrologic and nutrient budgets. The North St. Paul plan proposed preparation of a water quality study in 1995 for the Silver Lake watershed. Ramsey County requested that VBWD evaluate the current treatment efficiency of the wetlands and basins to the north (upstream) of Silver Lake. This evaluation would determine whether their existing treatment efficiency is within the range of expected efficiency. If the treatment efficiency is lower than expected, VBWD will determine whether maintenance or modification of the wetlands and basins is necessary to improve their treatment efficiency. Any wetland modifications would have to comply with the rules of the Wetland Conservation Act and VBWD. VBWD will consider evaluating current treatment efficiencies of the wetlands and basins upstream of Silver Lake in conjunction with the completion of hydrologic and nutrient budgets. VBWD will then determine the need to modify the upstream wetlands and/or treatment basins to improve their treatment efficiency. VBWD will also determine if maintenance alone will provide the needed improvement. Modifications to improve treatment efficiency can be expensive. 23\82\045\SEC4,RPT\KMH 3 DRAFT: June 23, 1994