A gaping hole in the spillway for the tallest dam in the United States grew Thursday and California authorities said they expect it will continue eroding as water washes over it but the Oroville Dam and the public are safe.
Earlier this week, chunks of concrete flew off the nearly mile-long spillway, creating a 200-foot-long, 30-foot-deep hole. Engineers don't know what caused the cave-in that is expected to keep growing until it reaches bedrock.
But faced with little choice, the state Department of Water Resources resumed ramping up the outflow from Lake Oroville over the damaged spillway to keep up with all the runoff from torrential rainfall in the Sierra Nevada foothills.
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