Mandatory evacuation order lifted for areas near Oroville Dam

"We've taken nearly 20 feet of the reservoir water surfaces out of the reservoir, which poses far less risk to all of the infrastructure we have here", Croyle said.

Siskiyou County Sheriff Jon Lopey said he sent a detective, a sergeant and a deputy to the area to assist. Crews working round the clock since Sunday have made progress stabilizing this and another spillway damaged by water.

Tens of thousands of families have been cleared to go back home after the threat of a catastrophic flood near California's Oroville Dam forced evacuations Sunday night.

The situation grew less dire later on Sunday as water levels dropped, leaving the weakened unpaved emergency spillway largely intact.

Lake Oroville Dam, located in the western foothills of the Sierra Nevada mountains, gets major inflows from the Sierras and will be tested again in the spring when the snowpack begins to melt.

The fixes could be put to their first test later this week with the first of a series of small storms forecast for the region.

In a letter dated February 13, the Federal Energy Regulatory Commission ordered the California Department of Water Resources to "initiate immediate design of emergency fix to minimize further degradation" of both structures, which have been eroding as water flows out of Lake Oroville this week.

The damaged main spillway has been stable for four days.

Mandatory evacuation order lifted for areas near Oroville Dam

"I think the public officials are in a tight spot where they have to play it safe and I understand that", Johnson said.

By Wednesday morning, officials said the lake level was low enough to handle rain from the next storm, Dan Brekke reported.

But evacuation orders for some 188,000 residents remain in effect indefinitely, Butte County Sheriff Kory Honea said at a midday news conference.

To relieve pressure on the dam, more than 2800 cubic metres of water per second were being released into the main damaged spillway, almost double its usual capacity. But just more than a week ago, a hole appeared in the concrete spillway off to its side and quickly grew as the surging water blasted off chunks of loose concrete and hurled them downhill.

"We continue to armor up the hillside", said Chris Orrock, a Department of Water Resources spokesman.

California's Department of Water Resources calculations show the snow pack is reaching near and in some places greater than the highest level recorded in 1983.

Meanwhile, a local attorney doesn't see a wave of lawsuits coming as a result of residents and businesses being displaced by the Oroville Dam evacuations.

"This allows people to return to their homes, allows people to return to their businesses", Honea said. Crews are using helicopters to line the eroded emergency spillway with bags of rock and sand to avert a disastrous released of uncontrolled water from the dam.

  • Larry Hoffman