On Monday, officials were able to begin drawing down the lake, but weather forecasts called for heavy rains in the next week. "This was a new, never-happened-before event".
Honea said residents should be prepared to evacuate again in the future if it becomes necessary.
Late on Sunday, about 188,000 residents were ordered to evacuate their homes in the Feather River valley below the dam, 65 miles (105 km) north of Sacramento. The agency did not disclose the other three people's names.
Another series of storms is headed for Northern California starting on Wednesday.
Right now in California, the nation's tallest dam is facing its toughest test yet - holding back about 1.1 trillion gallons of water while one of its auxiliary spillways, which acts as a relief valve, threatens to collapse.
Meanwhile, crews working around the clock atop the crippled Oroville Dam have made progress repairing the damaged spillway, reducing the lake level by at least 8 feet overnight at the Northern California reservoir.
In the mountainous folds of California lie hundreds of dams that play a vital role in making it America's wealthiest and most populous state.
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While the wet winter has been a boon for water supplies, it has created a challenge for water managers who must balance the need for water and hydroelectric power with protecting flatland communities from floods during times of excessive rain or rapidly melting snow.
Tuesday at 9 a.m., the lake's level had dropped to 888.68 feet, about 12 feet below the Oroville Dam's capacity of 901 feet.
"We're doing everything we can to get this dam in shape so that they can return and they can live safely without fear".
Jeffrey Kightlinger, the general manager of the Metropolitan Water District of Southern California, the water utility for Los Angeles and its environs, said the issue was not cost but federal guidelines, the Los Angeles Times reported.
Tuesday afternoon authorities lifted the evacuation order.
The Oroville Dam is 235m-high and holds more than 3 trillion litres of water. School officials say they will now remain closed until they are told by authorities that the area is safe. Erosion on the main spillway so far was manageable, See said. The main spillway is already damaged and running water started to erode the left bank of the spillway. Image by William Croyle, California Department of Water Resource, work is in the public domain. The groups warned of a complete failure of the dam itself, threatening lives and property. He also said DWR engineers will spend the coming weeks calculating whether it makes sense to fix the existing concrete structure or build an entirely new spillway nearby. Officials refused to update that figure Monday.
Brown sent a letter to President Trump requesting him to issue an emergency declaration, which would open up federal assistance for the affected communities.