Dockweiler State Beach and the northern half of Manhattan Beach — from Ballona Creek south to the Manhattan Beach Pier — will be posted with closed signs Tuesday though Thursday, and maybe longer if high bacteria counts are detected. It's not because of the rain, but for inspection of the sewage outfall pipe at Hyperion. The treatment plant usually dumps most of L.A.'s liquid effluent in an offshore canyon about five miles to sea. While that outfall pipe is closed for testing, the plant will use a pipeline that ends just a mile offshore in fifty feet of water.