patrick.net

As long as Republicans suffer ,who cares?

Didn't know where Oroville is, so I looked it up:

No news is good news says

Oh My

Could you report something useful instead of just jumping straight into the propaganda?

Probably just the beginning. When the snow pack melts. it's gonna be "When the Levee Breaks" in the Central Valley with all the runoff.

As usual, the reporting in the mass media is not very good, but from what I've been able to piece together:

At some point on Tuesday (today is Sunday), the main spillway had a big hole developing in the concrete pathway, and somebody made the decision to close that spillway to evaluate and/or repair. In the meantime, water in the lake rose quickly enough that the reserve/emergency spillway overflowed. This caused erosion below the emergency spillway, and raised concerns that the emergency spillway wall could fail . The main spillway was then activated again (10pm tonight it is operating at 100k cfps), and this has lowered the lake level enough that the emergency spillway is no longer overflowing. At the same time, 40k cfps is still arriving into the lake, but a drawdown of 50ft has been estimated to be needed to accommodate incoming storms and snowmelt next week.

The big question, I think, is going to be whether the initial closure of the main spillway was the right decision. Right now it looks like it was not the right decision, given that it has been reversed, but one might argue that the spillway needed to be inspected before re-opening. The duration of the closure time for inspection has not been revealed. There was some talk that the reasoning behind the decision was to ensure the safety of some power line towers that serve the dam's power station.

The best article I have found so far is from the Sacramento Bee newspaper. It is a bit convoluted, and the timeline is not so clear, but it has ghood information.

http://www.sacbee.com/news/local/article132154774.html

Early Friday, DWR officials had expressed confidence that they could avoid the emergency spillway option. Despite the crater in the main concrete spillway, engineers ramped up water releases to 65,000 cubic feet per second. With rains letting up, and inflows into the lake slowing, they believed they could keep the water level behind the dam to below 901 feet.

But Friday, at about 8 p.m., they had to throttle back the releases to 55,000 cfs to prevent erosion along the side of the main spillway from compromising the transmission tower that links to the dam’s power plant.

Normally, the power plant is the main vehicle for pushing water out of the lake. But DWR has temporarily shut the plant because all the concrete and other debris streaming into the river from the broken spillway has raised water levels to the point that the turbines can’t run. DWR needs the transmission tower to remain operational to be able to reopen the power plant

This photo gives the proper perspective. Note the emergency spillway, far left, and the regular spillway, the long concrete "waterslide" right next to it. The big earthen dam is not affected at all.

https://en.wikipedia.org/wiki/Oroville_Dam#/media/File:OrovilleDam.jpg