Dam Failure

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I just saw a news item saying a warning was issued for a portion of Northern Calif. that a dam is close to bursting. It is calling for evacuations. At the bottom it says "THIS IS NOT A DRILL" repeated three times.

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The Oroville Dam is not close to bursting!

The (man made) lake behind the dam is full due to large amount of rain in Northern California this season. There are two (2) spillways for this dam. The main spillway is damaged so the main spillway was shut down for several days this week (allowing the water level to raise almost to the point where water will "spill over" the "emergency spillway"). The lake is now completely full, water is again being drained using the damaged "main spillway" (which will further damage the "main spillway"!), and the "emergency spillway" will be adding to the water being released "downstream". There is a possibility of flooding downstream due to the massive amount of water being released. The recommended evacuations are just a precaution. Unfortunately, some news media are reporting "unnecessarily alarmist" reports of the dam being in danger of bursting. This is untrue. There is NO danger of the dam failing.

cautions

I wish it wasn't an overreaction but there is just cause for doing so. It sucks but sadly it's best to overdo it than get caught with their pants down.

I'm told STFU more times in a day than most people get told in a lifetime

Dam failing

While there is no real danger of the Oroville Dam failing outright, only the lip of the emergency spillway is concrete. The water then runs down the face of the earthen dam, eroding some of it away. The dam is 770 feet high (the tallest dam in the United States), so water falling down its face has a lot of force. Between the water going down the main spillway and that going over the emergency spillway, a lot of mud and debris was washing down the Feather River. Up to 100,000 cubit feet of water per second can go down the main spillway, but last week inflows were up to 190,000 cubic feet of water per second. That's a lot of water!

Fortunately, the rain has stopped for a few days, so the water level has dropped a little and is no longer going over the emergency spillway. However another series of storms will arrive Wednesday night, and they are predicted to drop up to eight inches in the mountains around Lake Oroville in the following week.

I'm glad my home in Oakland isn't downstream from any reservoirs.