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and discharges into a wetland on the south side of the DNR trail (DNR #82-373W). Water from the wetland flows in a ditch to Lake DeMontreville, The 100-year flood level of Long Lake was lowered about 4 feet to Elevation 943.2 as a result of the new outlet construction. One home on the lake is still in the flood plain. The first floor elevation of this home is at approximately 942.8; the basement is at an even lower elevation. The owner of the home chose not to participate in VBWD's residual floodproofing program, so the home is still in the floodplain. Another lakeshore home has a low walkout elevation at 943.3, just above the 100-year flood elevation. It is unlikely that VBWD will lower the 100-year flood elevation to prevent flooding of the lowest home on the lake. Without creating additional storage elsewhere, the only way the flood elevation could be lowered is by lowering the outlet elevation. DNR regulations will not allow lowering of the Long Lake outlet beyond that which is specified in VBWD's DNR-approved operating plan. 4.2.5.3 VBWD Water Quantity Management Goals VBWD computed the 100-year flood elevation of Long Lake assuming ultimate development in the watershed and the construction of new restricted outlets for Echo Lake and Weber Pond, in the City of Mahtomedi. Based on these upstream alterations, the Long Lake flood level will not increase as a result of development in the upstream watershed. However, it is important that the City of Mahtomedi maintain the culverts under Long Lake Road to ensure that the flood storage in the wetland north of Long Lake Road is available for storm events. If ravine erosion is shown to be a problem on the west shore of Long Lake, VBWD will determine if remedial measures should be taken to correct and prevent erosion problems, Such remedial measures could include ravine restoration, pipe installation and/or additional upstream stormwater detention. VBWD will continue to monitor Long Lake water levels monthly and supply the information to the DNR. 4.2.5.4 Water Oualitv and DNR Data A 1989 DNR fisheries survey of the north Long Lake basin showed higher than local average northern pike, panfish and bullhead catches. A 1982 DNR fisheries survey of the south Long Lake basin found average numbers of northern pike, panfish and bullheads. Because of the steep shores, emergent vegetation covers only a small portion of the lake surface. The 1989 DNR fisheries survey also noted water plantain and softstem bulrush on the sand delta on the southwest side of the north Long Lake basin. Curlyleaf pondweed was the abundant aquatic vegetation, especially in sheltered areas on the southwest and north sides of the lake. MDNR has no plans to stock the lake with fish since there is no public access. Access can be gained to the north basin from Long Lake Road on the north end of the lake, although this has become more difficult since the road was raised. It is also possible to access the south basin from the T.H. 36 south service road (Viking Drive). VBWD collected water quality samples in 1971, 1972, 1975, 1979, 1984, 1987, 1990 and 1993. The samples were collected from the north Long Lake basin only, except for one year when samples were collected from both the south and north basins. The lake is thermally stratified to a depth of 10to 20 feet in summer and the cold lower waters (hypolimnion) show almost no oxygen present. Total phosphorus concentrations are higher in the hypolimnion, indicating that internal loading may be a significant factor in determining the water quality of the lake. Summer total phosphorus concentrations have averaged 0.050 mg/L. Residents 23\82\045\SEC4.RPT\KMH 13 DRAFT: June 23, 1994