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point elevation connecting it to West. Vadnais Lake (881.2+/-, 1988 datum) for the vast majority of time. An extended wet period (precipitation exceeding the annual average) may reduce the rate of infiltration from Grass Lake and result in an increase in lake level. It is at such times that the Grass Lake elevation may be high enough to move water to West Vadnais Lake. The immediate watershed to West Vadnais Lake is small and water level in the lake corresponds to local ground water levels and the water flowing into it from Grass Lake on an intermittent basis. The water levels of Grass Lake and West Vadnais Lake are thought to be similar during high water periods, although there are limited West Vadnais Lake elevation data to verify this belief. The proposed West Vadnais Lake outlet will provide an outlet for both Grass Lake and West Vadnais Lake, on an infrequent. basis, into the Ramsey Washington Metro Watershed District and Gervais Lake. Prior to construction of I-694, West Vadnais Lake's outlet was provided by surface flow to the south, through Black Tern Lake and into Gervais Creek, flowing to Gervais Lake. This flow path was eliminated by construction of the highway in the 1960's. A secondary potential outlet from West Vadnais was then constructed incorporating a short section of pipe and ditch (actually a deep ravine) to Twin Lake. Over time, the ravine was filled in with demolition rubble and the east end of the pipe section was blocked and eventually covered by a storm shelter building. The proposed West Vadnais outlet pipe alignment ends at Jiggs Pond rather than Black Tern Lake because the water level of Black Tern Lake has been manipulated (raised) over the years by development grading and construction of an outlet. pipe. The remaining procedural steps for the proposed West Vadnais outlet project include identifying project partners, finalizing project design elements and costs, submitting a joint notification permit application, developing an operations and maintenance plan, preparing joint powers cost-share agreements with MnDOT and project partners, and obtaining approvals from affected water management organizations and cities. Available information on these steps is summarized below: . 1, `Unweave the Weave' Project - Plans/ Cost -Total West Vadnais outlet cost estimate is unavailable as yet. Installed pipe and structure costs alone $79,190. Additional costs include design, road restoration, erosion control, and 8% contract administration. Rough estimate total cost$150,000. - Schedule - 95% construction plans due June 18, 2004. 100% plans by mid September. Let `Unweave' contract December 2004. Begin construction April 2005. First year little disruption of existing pavement. Ponds and off-road features constructed early. - Cost participation agreement - MnDOT prefers agreement (prepared by MnDOT by mid September) with. one agency and separate JPA among partners. 3/19/2004 3