Water poured from a massive lake formed by China's deadly earthquake in a carefully engineered diversion to ease the threat of flooding for a million people in the sprawling disaster zone.  After two weeks of frantic work by engineers and soldiers, waters flowed into the hurriedly built spillway, but at a rate too slow to cause the lake's level to drop.  Military engineers dynamited boulders and soldiers used excavators Saturday to deepen the channel to accelerate the flow, state media said.  "The lake was still dangerous despite the draining,'' the official China's News Agency quoted Minister of Water Resources ChenLei as saying.