OROVILLE, Calif. -- Authorities have lifted an evacuation order for nearly 200,000 California residents who live below a dam with a damaged spillway that threatened to collapse and cause catastrophic flooding.

Butte County Sheriff Kory Honea said Tuesday that residents should stay prepared in case the situation changes. He says the water level at the lake behind Oroville Dam, the nation’s tallest, is low enough to accommodate expected storm.

Crews have working around the clock atop the crippled Oroville Dam, making progress on repairs ro the damaged spillway. The work led to the lake level reducing by at least 8 feet overnight at a Northern California reservoir that has been central to the life of the towns around it for a half century.

Workers hoisted giant white bags filled with rocks, and at least two helicopters planned to fly in rocks Tuesday then release them into the eroded area of the spillway. Dump trucks full of boulders also were dumping cargo on the damaged spillway.

The lake that for five decades has brought residents holiday fireworks and salmon festivals could have brought disaster.

“Never in our lives did we think anything like this would have happened,” said Brannan Ramirez, who has lived in Oroville, a town of about 16,000 people, for about five years.

Recent reports indicate that environmental activists and local government officials warned more than a decade ago about the risk of catastrophic flooding below a major Northern California dam, the very scenario that threatened to unfold in Oroville over the weekend.

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