The $23 billion of commerce that flows along the Columbia River will pause for two weeks beginning March 2 as the U.S. Army Corps of Engineers Portland District closes three navigation locks for annual inspections and maintenance.  The closures of the Bonneville, The Dalles, and John Day Locks will continue through March 16.  The closure will include annual inspections and routine maintenance, as well as additional rappel inspections at John Day by a Corps of Engineers climbing team.  Typically, the Portland and Walla Walla districts coordinate their annual lock closures across the Columbia-Snake River System.  This year, each district is notifying the public separately due to different closure periods.   Walla Walla District’s lock closure began January 14 and ends March 29.  The Corps coordinates the annual lock closures with inland shippers and cruise lines to minimize the impacts to those users.  Portland District’s locks on the Columbia River pass 10 million of the 50.5 million tons of commerce shipped annually in the nation.