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• Bedload - Bedload is the heavier coarser fraction of the sediment load transport to the lake from the river; the sand moving along the bottom. The estimated rate of bedload entering Lake Orono from the Elk River is 3,000 cubic feet peer year. This is not a high rate. The banks of the Elk River are fairly protected with stabilizing vegetation. These vegetative buffers must be protected by working with the Elk River Watershed Board. However, even at this relatively low rate, given time the lake will revert back to a river. The delta of bedload from the river has made navigation in the western most lobe of the lake nearly all but impossible. It is estimated that within 50 years the next lobe of the lake,just north of the Highway 10 bridge, will be equally effected. Bedload is the real issue that the lake improvement project is addressing. For more details on bedload see page#11 of the attached study. PROPOSED LAKE IMPROVEMENT PROJECT The city is proposing to remove and/or grade approximately 115,000 cubic yards of sediment to improve Lake Orono. The Lake is proposed to be drain in early August for the project. The sediment will be bulldozed into windrows, loaded into off-road trucks with backhoes, and disposed of on sites adjacent to the lake. The Elk River, which will continue to flow through the lake during the project, is proposed to be redirected away from construction activities. The project is proposed to be completed by October 31st and III the normal water level of the lake will be restored shortly afterward, prior to freeze-up. Question#6 (Description) in the attached EAW gives a detailed account of the proposed project. Sediment Removal In October of 1997, the lake was incrementally lowered and aerial photos were taken so that the sediment deposits could be delineated(see Map #1 attached). The Sedimentation Task Force reviewed fifteen areas within the lake for possible improvement or sediment removal. The fifteen areas reviewed are designated as "A" through"0" on Map #2 attached. The areas selected for improvement were based on overall functioning of the lake (keeping the lake from reverting back to a river), navigation and safety. The areas recommending for improvement in descending order of priority are as follows: • Area L - Area"L" is the western most lobe of the lake. The waters of the Elk River slow enough in this area to deposit bedload. The bulk of the sediment removal will be from this area to restore it to its original navigable depth and act as a basin for future sedimentation.