Lucky Peak Reservoir and state park on the Boise River east of Boise. (Idaho Department of Parks and Recreation/Contributed)The U.S. Army Corps of Engineers and partners on Aug. 10 plan to start drawing down Lucky Peak Reservoir on the Boise River in preparation for fall and winter operations. Of the river’s three main reservoirs, Lucky Peak is the farthest downstream and closest to Boise. “But current projections are for a fairly typical shutoff date,” a decision to be made by the Boise River water master. “Irrigation demand out of Lucky Peak is a little lower than we’ve seen in the past couple of years,” he said.