OROVILLE, Calif. (KGO) --The water level has dropped at the Oroville Dam but emergency officials are not taking any chances.
RELATED: No end in sight for Oroville evacuations, residents make due
Several communities have been evacuated from the flood zone in case the dam's emergency spillway fails.
Over 188,000 people don't know when they can return home. They grabbed what they could and got out. Emergency officials are worried erosion will move into a concrete wall under the spillway, sending a wall of water into the valley.
Crews are working to shore-up the spillway. It eroded over the weekend after being used for the first time in nearly five decades.
The governor has been briefed on the situation and has requested direct federal aid.
One after another--and endless procession of dump trucks carrying huge boulders from a staging area to the damaged emergency spillway of the Oroville Dam.
This is an effort Governor Jerry Brown says he's watching closely. "The evacuation is still in place and there is an uncertainty, better be safe than sorry what exactly it is about engineering. It's about construction. It's about repair."
Earlier Monday helicopters dropped bags of smaller rocks to help close the gaps in the makeshift repair, one that engineers hope will shore up the nation's tallest dam, at least for now.
In the meantime, downtown Oroville is mostly evacuated. The lights are on and all but a few businesses are closed.
VIDEO: Oroville Dam emergency spillway at risk of failing
Local police are among the few vehicles on the road checking to make sure that looters don't move in while thousands of residents are away.
Many of the evacuees from various towns have headed to shelters in places like Colusa, Chico--anywhere that's out of the way of a potential disaster.
"My daughter wanted me to get a place to stay, maybe three or four days until they work this out," said evacuee Pat Dailey. "Figure out if it's going to work."
All of the evacuees are well aware that there's another round of rain headed their way.
"As it comes right now I wouldn't say that everything's going to be fine," said Chance McBrayer. "We know a storm's coming. We don't know how big it is."
"I don't think we're out of the woods yet," said another evacuee Melinda Mangum. "Mess we'd be in then."
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