Through Mud and Sun to Fremont

[kevin_standlee]

It was a mostly uneventful trip from Fernley to Fremont today, although I wasn't expecting an hour delay at the Nevada-California state line as a long line of vehicles inched their way through the area was where one of the mudslides was being cleared.

I stopped in Sacramento and visited my sister for 30 minutes. Not much change to report there. I gave her some Aero chocolate bars that Lisa had given me for Kelli.

When I got to Fremont, I saw the news that the emergency spillway at Oroville Dam was in danger of failing and that downstream areas, which includes where lots of my relatives live, were under threat. I called my mother, who lives in the Yuba County foothills and is not in the flood zone. I tried to explain that reports that the dam itself had failed were untrue,  albeit that the actual situation is not great. Clearly many people don't understand the difference and assume that if the emergency spillway fails, all the water in the lake drains out. As one person on Twitter helpfully explained,  there's a difference between 30 feet of water and more than 800 feet of water draining from the lake. We haven't heard from my nephew, but he lives in Sutter, and that is high ground. Even if the entire lake were to drain, Sutter stays dry, albeit it temporarily becomes an island.

I'm writing this entry on my phone, which is harder than a regular keyboard,  so more updates will have to wait

Comments

[msconduct.livejournal.com]

I heard about this on the BBC World Service, although they seemed to think the crisis was over. I wondered whether the problem was part of the situation with general US infrastructure decaying and not being repaired that's been going on for a long time.

[kevin-standlee.livejournal.com]

It may be, but it's also related to the fact that the emergency spillway has never actually been used before, so they didn't really know how it would behave . We've been in a drought for a long time, and now that the rain has finally come, we have more than we know what to do with, even with huge water storage facilities like Oroville, which is one of the biggest dams in the country.

A complete failure at Oroville (which appears unlikely) would be both immediately catastrophic and also long-term so, because it's the linchpin of much of California's water supply.

[nojay.livejournal.com]

As I understand it the problem is with the emergency spillway which has never been used before -- the normal spillway is operating at full capacity but there's still too much water in the reservoir. If the emergency spillway does break and gets washed away then there will be a lot of water suddenly headed downstream but not as much as if the dam itself gives way (which doesn't seem to be at risk).

[kevin-standlee.livejournal.com]

Yes, that's about it, exacerbated by how they had shut down the regular spillway for a while because it has developed a gaping hole in the concrete. But they decided to go ahead and open it back up full tilt because they must get water out from behind the dam, which was at 100% capacity, in order to make room for the next batch of storms.