KAHLOTUS, Wash. – Vehicle crossings at Lower Monumental Lock and Dam, located at Snake River Mile 41.6 near Kahlotus, Washington, will be closed Tuesday, Aug. 28, through Thursday, Sept. 6, to accommodate spillway-maintenance activities involving workers and heavy equipment using the top of the dam, according to operations officials with the U.S. Army Corps of Engineers’ Walla Walla District.