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and Jamaca Avenue North in subwatershed JAN12. From there, water was to discharge rly through two ponds, eventually reaching Lake DeMontreville. The proposed system to operate as a low -flow bypass, with higher flows discharging to Lake Jane. Such a ,ped discharge would be beneficial in terms of preserving Lake Jane water quality. ,Never, VBWD will not pursue such an option because of the water quantity and water ality impacts to Lakes DeMontreville and Olson, /Eighteen homes were within the flood plain of Lake Jane, Hedges Bog, Hedges Pond, eer Pond and Crombie Pond prior to construction of VBWD's Project 1007. Because the lake had no natural outlet, large long-term fluctuations occurred in the lake level. Analyses indicated that the 100-year flood level without pumping was Elevation 932, The OHW of the lake was set by the DNR at 924.0. In 1979, the Managers of VBWD installed a small pump and f pipeline on the south shore of Lake Jane. Water was pumped from Lake Jane to City Park Pond every year until 1987, with the exception of 1980. Figure 4-12, prepared by the DNR, shows historic Lake Jane water levels from 1968 to the present. VBWD began monitoring lake water levels in 1969; the VBWD data is included in the graph. In August, 1986, Lake Jane reached Elevation 927.4, a record high. The flooding which occurred as a result of the high water in the early to mid -eighties caused approximately a million dollars in property value reduction on Lake Jane. A City of Lake Elmo ordinance requires a no -wake zone on Lake Jane, beginning when water levels reach Elevation 924.0. The construction of an outlet from Lake Jane in 1987, as part of Project 1007, lowered the 100-year flood elevation from 932.0 to 926.0. Water from Lake Jane flows to Hedges Bog and Hedges Pond via ditches. The Lake Jane outlet structure controls the water level on Lake Jane, Hedges Bog and Hedges Pond. The outlet consists of 30-inch diameter pipes into and out of the control structure and is located approximately 20 feet north of the old outlet pipe. A 6'fi- foot diameter manhole located in Deer Pond Trail contains the control structure, which consists of a weir and stoplogs. The top of the stoplogs is at Elevation 922.35. Stop logs can be than three inches is anticipated. The maximum allowable drawdown is to Elevation From Hedges Pond, water flows in a 30-inch pipe in Deer Pond Trail, combines with the Deer Pond outflow near the intersection of Jack Pine Trail and Deer Pond Trail, and discharges to the northwest shore of Crombie Pond. The Crombie Pond outlet is comprised of 30-inch diameter pipes into and out of an 8-foot diameter control structure located in Lake Jane Trail (42nd Street North), west of Irish Court. A weir and stop logs control the outflow from the pond. The top of the stop logs are at Elevation 921.5. According to a DNR-approved operating plan, the stop logs can be removed only when snowmelt runoff greater than three inches is anticipated. The maximum allowable drawdown is to Elevation 919.0. Under normal conditions, Lake Olson water will flow to Deer Pond, Crombie Pond and then to Eagle Point Lake. When flow rates exceed about 13 cfs; water will flow from Deer Pond to Lake Jane, as well as to Crombie Pond. As inflow abates, the stored water on Lake Jane will again flow to Deer Pond and out of the Tri-Lakes system. Approximately 80 percent of the long-term hydraulic loading from Lake Olson is predicted to bypass Lake Jane. After the initial drop in water level resulting from construction of VBWD's Project 1007, Lake Jane's water level dropped even further because of drought conditions. Lake Jane did not reach its discharge elevation again until the spring of 1993. When Lake Olson and Lake Jane water levels were at their peak in July,1993, water was still flowing from Lake Jane to Crombie Pond. Seven homes in the Lake Jane area were still within the flood plain after construction of Project 1007. Five of the homes were on Lake Jane, one was on Deer Pond and the other was 23\82\045\SEC4.RPT\KMH 30 DRAFT: June 23, 1994