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4. Work with the watershed board and the comprehensive water plan committee toII <br /> develop a water quality action plan to address: <br /> • best management practices within the Elk River watershed - The sedimentation rate of <br /> the Elk River is very low when compared to other rivers monitored by the USGS in <br /> Minnesota. Much of the river is lined with natural buffers. However, the <br /> sedimentation rate could be reduced the natural buffers should be maintained. <br /> • water quality goals for the Elk River watershed -A member of the Lake Orono <br /> Improvement Association has recently been appointed to the Sherburne County Water <br /> Plan Committee and will be acting as a liaison for the city. <br /> Sediment removal <br /> The removal of sediment from the lake described in study recommendation #2 is the issue <br /> that mandates the EAW process. The lake study found that there was no net deposition of <br /> suspended sediment in Lake Orono and the sedimentation that does exist consists of <br /> primarily the coarser bedload fraction of the Elk River's sediment load. <br /> The city is proposing to remove 1 to 2 feet of sediment from the western most lobe of the <br /> lake (Area I, approximately 90,000 cu. yd.) to restore its original navigable depth. This <br /> lobe will again act as the sedimentation basin for bedload from the river in the future. <br /> 411 <br /> In addition, the city plans to remove sediment that poses a safety hazard to boating from <br /> two other areas of the lake (Areas II, 3,500 cu. yd. & Area IV, 13,500 cu. yd.). <br /> Approximately 2,000 cu. yd. is proposed to be removed from Area III to improve access <br /> and clean out an existing area where sediment currently deposits. <br /> An optional area the city is considering involves the removal one foot of sediment from <br /> the top of four high spots that pose hazards to boating. The material removed from the <br /> high spots mentioned is proposed to be left on adjacent areas of the lake bed, away from <br /> the channel of the river through the lake. The location of this material precludes its <br /> removal without bridging the river channel through the lake or repeatedly cross it. It is <br /> our opinion that both of these options would have a negative effect on water quality. This <br /> work involves the moving of approximately 6,000 C.Y. of material. <br /> A total of approximately 115,000 C.Y. of material are proposed to be removed and/or <br /> graded by the project. The total project area encompass 61.9 acres. For details on the <br /> locations, quantities, and depths see the attached sheet 1 of 2 of the attached Lake Orono <br /> Improvement Project Site Plan. <br /> III <br />