Oroville lake, the emergency spillway, the damaged main spillway, and the earthen Oroville Dam are seen behind the town of Oroville from the air on Feb. 13, 2017 in Oroville, California.
Almost 200,000 people were ordered to evacuate the northern California town after a hole in the emergency spillway in the Oroville Dam threatened to flood the surrounding area.
The order was reduced to a warning on Tuesday, allowing residents to begin returning — with the caution that the condition of the dam that imperils the area could still change quickly.
A home is surrounded by floodwater in Oroville on Monday.
Workers are rushing to repair the barrier at the nation's tallest dam amid concerns the spillway could fail and send water roaring downstream.
A few locals who stayed behind watch the Feather River from Table Mountain Bridge in Oroville on Monday.
State Department of Water Resources officials hope to reduce the lake level to 860 feet by Thursday, when storms are expected to bring more rain, spokesman Chris Orrock said. The level was 884 feet on Tuesday morning.
Richard Kelly distributes water Monday at a Red Cross relief center in Chico, California, after the evacuation was ordered for communities downstream from the Lake Oroville Dam.
Evacuees rest at a shelter in Chico on Monday. The thousands of people who were ordered to leave their homes may not be able to return until significant erosion is repaired.
Katherine Boeger Knight, left, plays a card game with her daughter Amethyst, 5, at a shelter on Monday.
A playground is submerged in flowing water at Riverbend Park in Oroville on Monday.
The Gold Rush town in the Sierra Nevada foothills, some 70 miles northeast of Sacramento, is nestled near the foot of the dam, which was completed in 1968 and at 770 feet is the nation's tallest. Houses and churches are perched on tree-lined streets near the Feather River. Old, ornate Victorian homes sit alongside smaller bungalows.
An orchard is turned to swamp land as floodwaters rise near Oroville on Monday.
The region is largely rural, with its politics dominated by rice growers, orchard operators and other agricultural interests. The region is dogged by the high unemployment rates endemic to farming communities. There are large pockets of poverty and swaths of sparsely populated forests, popular with anglers, campers and backpackers.
The California Department of Water Resources suspended flows Feb. 7 from the Oroville Dam spillway after a concrete section eroded on the middle section of the spillway.
Boulders are prepped to be used on the Lake Oroville Dam on Monday.
A helicopter flies over the Oroville dam with bags of rocks to shore up the emergency spillway of the dam after overflow from the lake crested it's maximum capacity and caused erosion.
Helicopters carried giant sandbags and cement blocks from a staging area on the south side of the dam toward the stricken spillway on the north side.
Members of the Jordan Crossing Ministry of Oroville, pray for Marine Russell Bluxome Monday at a Red Cross relief center in Chico, after the evacuation order.
Desiree Garcia and her daughter Kay'lee, of Oroville, sift through donated clothing at a Red Cross relief center in Chico, on Monday.
Riverbend Park is covered floodwater in Oroville, on Monday.
California Department of Water Resources crews inspect and evaluate the erosion just below the spillway site after lake levels receded on Monday.
Crews working around the clock reported progress Tuesday in repairing the damaged spillway and reducing the water level by at least 8 feet at the reservoir that has been central to this farming region for a half century.
The Oroville Dam spillway releases 100,000 cubic feet of water per second on Monday.
Dump trucks carrying rocks and boulders cross the Oroville Dam as emergency personnel work through the night to dump them on the damaged portions of the dam on Monday.
Evacuees Colette Roberts and her daughter Lesilee watch a video at the Neighborhood Church of Chico on Monday.