MCGREGOR, Minn. — The Sandy Lake Recreation Area will reopen for camping in May following a two-year updating project on the Sandy Lake Dam, the Army Corps of Engineers announced. The Corps replaced six gates and deteriorated walls in the lock chamber. It also installed a new slide gate in the log sluice chamber and replaced the 130-year-old timber upstream apron. The dam is midway between Brainerd and Duluth.