Water levels begin to recede at US' tallest dam

By Michael Hernandez

WASHINGTON (AA) - Water levels have begun to decline at the tallest dam in the United States on Monday, halting an overflow that threatened to destroy the dam's emergency spillway.

Still, as of early Monday morning 100,000 cubic feet per second continued to flow down the Oroville dam's main spillway, the California Department of Water Resources said.

On Sunday night, California Gov. Edmund Brown issued an emergency order aimed at bolstering the state's response to the potential calamity as roughly 180,000 residents fled their homes.

Brown warned that the situation is "complex and rapidly changing", and said "the state is directing all necessary personnel and resources to deal with this very serious situation.”

Hundreds of cars brought traffic on Highway 99 to a standstill after the evacuation order went out at around 4 p.m. (0000GMT) Sunday following a notice from engineers that the emergency spillway was damaged.

Authorities warned that should the structure fail communities in the river basin could be struck by a potentially devastating 30-foot (nine-meter) tall wall of water.

Officials are now scrambling to repair the 30-foot-deep hole on the lip of the secondary spillway before more rain hits the region Wednesday and into Thursday.

The U.S.' disaster response department, FEMA, is working with local authorities to address the situation, and currently has an incident management team on the ground.

The overflow began after a series of heavy storms dumped massive amounts of rain and snow on northern California, where the dam serves as a reservoir.

The 770-foot tall (235-meter) earthfill embankment dam was opened in 1968 and is located east of the city of Oroville. It is located roughly 65 miles (106 kilometers) north of the state capital, Sacramento.