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A consultant to MnDOT has completed the preliminary engineering design. This information includes a proposed alignment and profile (grade or slope) of the 15-inch diameter pipe from West Vadnais Lake, under I-694, and ending at Jiggs Pond, located between Levitz Furniture and the former Knox Lumber building along Country Drive in Little Canada. Jiggs Pond will be modified as part of the `Unweave' project, to a configuration with surface area of about 1.25 acres and depth at normal water level of 3 feet. The consultant also completed hydrologic modeling of the existing condition at Jiggs Pond as well as the proposed condition after the `Unweave' project. For the "after" condition, the effect of the West Vadnais outlet flow is estimated conservatively as 4 cubic feet per second, which corresponds to the outlet pipe flowing full. This condition is' extremely unlikely to occur in practice, once the West Vadnais Lake level is set at the control elevation of 881.9. Modeling results for the Type II, 24-hour, 100-year storm event of 5.90 inches, for existing and proposed (i.e. with `Unweave' project and full pipe flow in the West Vadnais outlet pipe) conditions at Jiggs Pond are summarized in the Attachment 2 (below). A brief summation of these results is the proposed combined `Unweave' and outlet projects do not increase storm event peak outflow and high water elevation at Jiggs Pond, but each project will individually add some water volume to Gervais Lake in the total amount flowing through the outlet pipe over time. For long periods of time, there will be no flow out of the West Vadnais outlet pipe. Once the outlet is in place and. the control water elevation is reached, when outflow does occur, it will usually consist of a very low flow or trickle due to the limited inflow to West Vadnais Lake and the large lake surface area. The purpose of the proposed outlet is to provide an upper limit to West Vadnais Lake elevation during long-term periods of above-normal precipitation, such has occurred in the last several years. The proposed West Vadnais outlet project involves water flow between three water management organizations: Vadnais Lake Area WMO, Grass Lake WMO, and Ramsey- Washington Metro Watershed District. Grass Lake and West Vadnais Lake may exchange water during high water periods. Grass Lake elevation has been markedly elevated since 2001 (extended periods above 882.7, 1988 datum), mast obviously encroaching on the I-694 Right-of-Way fence and flooding the bike pathway under Gramsie Road in Shoreview. The highest point controlling flow between Grass Lake and West Vadnais Lake is thought to be a culvert under a Metropolitan Council interceptor sewer access road on the east side of Grass Lake, with bottom-of--pipe elevation of about 881.2 +/- (1988 datum, extrapolated from Profile 4, Grass Lake WMO Level Control Plan, April, 1990). Grass Lake's watershed is approximately 1,389 acres and includes outflow from Bennett, Wabasso, Owasso and Snail Lakes in Roseville and Shoreview.. Grass Lake is a shallow lake, which. has been largely vegetated until recent high-water conditions created a much larger open-water area. The Grass Lake WMO Water Management Plan discusses the important role of infiltration or seepage from Grass Lake into the groundwater. Evapotranspiration by plants is also an important process, which consumes water in Grass Lake during periods when vegetation is abundant in the lake. According to long- term lake elevation data collected by Ramsey County, Grass Lake is well below the high 3/19/2004 2