Crews on Friday began the dangerous task of removing debris from the bottom of the damaged emergency spillway at the Oroville Dam.
The Department of Water Resources continue to reduce the flow to allow work down below and to make room in the reservoir for rain this weekend's storms are bringing in.
"We still have a lot of room where the water can be absorbed into the reservoir," said Chris Orrock with the Department of Water Resources.
On Friday, a fairly large stream of muddy water began flowing alongside of the spillway. Experts are closely watching it for signs of trouble.
"We're looking to see if that water is digging into the side of the mountain or creating further erosion in the flood control spillway," Orrock said.
Meanwhile, people in town are incredibly nervous.
"I'm doing a lot of praying," Oroville-resident Brian Kinzey said. "I'm sure my wife is too."
The goal is to drop the Northern California reservoir's water level 50 feet overall by Sunday, which would mark a week after an emergency was declared at the nation's tallest dam due to a damage on both its spillways, prompting a massive evacuation.
Crews from the DWR, CalFire and the Butte County Sheriff’s Office have been working round the clock since Sunday, when the dam’s emergency spillway looked like it would crumble, possibly leading to a flood for the homes and business of residents who live below.
The Associated Press contributed to this report.