OROVILLE -- California's Department of Water Resources is scrambling to allay the fears of people who live downstream of Oroville Lake after large sections of a spillway there crumbled.
The lower third or so of the spillway at Lake Oroville Dam is completely blown out by the 35,000 cubic feet of water per second rushing over it. The water is instead cutting its own channel in the hillside. That started in the early morning hours of Thursday. By Thursday afternoon, a new break had developed in the sidewall of the spillway on the left toward the top.
"We're just going to continue to use it and let the water flow out of Lake Oroville. We know it's causing lots of damage to the lower part of the spillway, but we're accepting that damage right now," said Eric See, spokesperson for the California Department of Water Resources.
DWR is still controlling the flow of water through gates at the the top. They could shut it down.
And there is another option: a ravine to the left of the damaged channel that serves as an emergency spillway.
But letting Lake Oroville fill up to the point that emergency spillway activates could create a massive, uncontrolled flow of water, sending trees and debris downstream.
"I want to be clear, we'd like not to. We're making every effort we can to not have to use the emergency spillway," See said.
Still crews are clearing the trees and brush from that emergency spillway just in case, so that material wouldn't slam into, or damage, the gates of a dam further downstream if the emergency spillway was activated.
The DWR announced late Thursday that the emergency spillway could be used as soon as Saturday morning.
The DWR has also moved a salmon hatchery further downstream, as the eroding spillway has the water near the dam too muddy for the salmon.