TUOLUMNE COUNTY, Calif. (CBS13) – Heavy rain brought raging waters to Moccasin Dam in Tuolumne County, leading officials to worry the dam was near imminent failure.  Highways 49 and 120 were both blocked off for part of the day, as people in the immediate area evacuated.

“This is the worst I’ve ever seen it!” said Vicki Webster, who has lived in Jamestown for 26 years.  “Very seldom do we see them open the floodgates on the dam. This is a rare sight”

Todd Elmer with San Francisco Public Utilities Commission said heavy snow and rain put extra pressure on Moccasin Dam.  Officials scrambled to evacuate residents and employees as they evaluated the threat of flooding in the area.

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“The best news of the day is that that dam seems much safer now,” said Rick Estrada, a spokesperson with CalTrans, District 10. “Any time you get back up, water is going to start eating into the edge of the river banks.”

The Moccasin Creek Hatchery sits just below the Moccasin Dam.  Employees with the California Department of Fish and Wildlife quickly evacuated Thursday afternoon. But the water inundated the hatchery, flushing the fish directly towards into Don Pedro Reservoir.

“We’re going to lose a lot of these fish,” Webster said.

“There’s a lot of them escaping right now,” said Sara Lopez, who lives nearby. “I think someone needs to get some nets and save some of them right now.”

The rushing water caused debris to pile up on Moccasin Creek, which pushed the water into highway 49. Part of the road collapsed and washed away into the creek.

“The tough part about fixing this is going to be weather-wise,” Estrada said.

Many drivers rely on this stretch of Highway 49 to get from Mariposa to Yosemite.

“It’s an incredible part of the county,” Estrada explained. “Tourism, businesses, people working. The last thing CalTrans wants to do is have a negative effect on that.”

Highway 120 opened up to traffic but Highway 49 remains closed until further notice.

Webster just hopes the water continues to subside.

“This is mother nature, in all her wrath and fury,” she told CBS13.

Much of the water supply for the Bay area passes through Moccasin Creek and Reservoir supplying 2.7 million people. Officials with San Francisco Public Utilities Commission say the dam is now stable and there is no disruption to the water supply.

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