AUBURN, Calif. (AP) – A broken release gate at a Sierra Nevada reservoir sent a wall of water down a river Thursday morning, threatening a highway and forcing the evacuation of campers along the river.

The sudden release of water from Ralston Reservoir south of Auburn sent a “wall of water three- to four-feet high” down the Middle Fork of the American River, said California Highway Patrol spokesman Tom Marshall.

The CHP was monitoring the muddy water as it approached Highway 49, a major road through the Sierra foothills.

A CHP helicopter flew the length of the canyon, using its public address speakers to warn anyone near the river to flee to higher ground. Authorities warned campers in one riverside site to evacuate.

There were no immediate reports of injuries or damage along the river, which is popular with rafters, kayakers and residents fleeing the summer heat.

Authorities said it might be hours before the flood reached Folsom reservoir.

AP-ES-08-05-04 1255EDT

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