Talked to a tacoma water guy today on a job. Said Riffe is permanently lowered due to the Oroville dam break in California. And if someone says it can happen, or it does happen somewhere else, they have to take action everywhere. He said some dams monitor flood zones, some dams monitor power and some such as Riffe, monitor both. Dams that are designed for both are a battle because the flood monitoring side wants the water level low and the power side wants it high. His opinion was that over time, some planning and funding will come up to update what is needed and bring it back to what it was. I thought his point of view was rather interesting.
Sorry for an old thread, but just in case there are folks here who are not up to speed on Riffe Lake, I wanted to get out real information.
So, regarding a "tacoma water guy" He lied, you misunderstood him. It's all about new USGS Seismic numbers that suggest a possible failure on the Mossyrock Dam Spillgates should there be a major event with movement in the East / West direction. It's a long shot anything like that will happen, but until such time the USGS issues new guidelines, the draw down will continue. The new seismic numbers are overdue by more than a year so far. Nothing like the slow motion of the US Government when decisions need to be made.