What's going on at Folsom Lake, California

[OnlinePoker]

At the beginning of January, lake levels stood at 403 feet and the reservoir was at about 40%. With the great rains they had over the first two weeks of the year, that level zoomed up to 440 feet and the lake was at 72% capacity. They've released so much water in the last week and a half, it's back to 400.77 today and 39% capacity. I know there's a good snow pack above the lake right now, but as we've seen over the past few years, there's no guarantee they will get any more water before the end of the rainy season. Wouldn't it be better to go into the dry season with a full reservoir and moderate the level based on the melt when you know how much is coming? It seems like all the other river systems are allowing their reservoirs to fill but the American River managers aren't. Why?

http://cdec.water.ca.gov/cgi-progs/reservoirs/RES
http://cdec.water.ca.gov/cgi-progs/queryDaily?FOL

[ghostsinthemachine]

1. Folsom has always been kept lower

Than other reservoirs. I've lived in walking distance of the lake since the 70s and known many water agency people, including my ex FIL, who was hired the day they broke ground to build the dam. The reason? Because all forks of the American pour into the lake, without any dams upstream to regulate the flows. Most of the Sierra snowpack drains into the American. And right now, there is A lot of snow accumulation in the Sierras. 12 feet along the freeway, probably 20 feet or more at the top, with a lot of rain and snow on the way. So the flows into Folsom will be high in spring (as with all dams) and summer and the lake would overflow if it weren't kept at lower levels. And if they did the releases in spring and summer, it would create environmental issues then. All concerning fish, the Delta etc. Not to mention create best danger along the American River with high water (danger) and flooding at the confluence in Sacramento. Prime recreation in summer, not so much now.

[OnlinePoker]

2. Thank-you very much for the detailed explanation. n/t