Almost 200,000 people were ordered to evacuate in Northern California on Sunday after an emergency safeguard for the tallest dam in the U.S. nearly failed, causing water to overflow.

Though officials said the immediate danger had passed by late Sunday, the problem identified at the Lake Oroville dam in Oroville, California, serves as a reminder of a common infrastructure dilemma: many of America's dams are in a state of disrepair, according to a 2016 report by the Centers for American Progress (CAP).

There are about 84,000 dams in the country, and the average age of these structures is 52. In 2013, the American Society for Civil Engineers (ASCE) estimated that there are about 12,000 high-hazard dams and 2,000 dams that are "deficient." The organization gave the United States a "D" grade for its dam infrastructure.

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In spite of these statistics, the only time dam infrastructure seems to be taken seriously at the national level is when a dam fails or nearly fails, Jenny Rowland, research and advocacy associate at CAP's Public Lands Project, told ATTN: Monday.

"Overall, the state of dam infrastructure is pretty poor," Rowland said. "There are thousands of aging dams, deficient dams, outdated dams, hazardous dams across the country that really we don't have a comprehensive recent policy to address their conditions." 

The Oroville dam situation was reflective of this infrastructure issue, she added. After five years of drought, California has experienced record-high rainfall this season, causing water levels at dams across the state to climb dramatically. The dam's emergency spillway, which is used when water levels reach capacity, apparently had a hole in it from erosion that nearly caused the system to fail.

Workers started plugging the hole with bags of rocks on Monday, a temporary fix that should allow the emergency spillway to function, The Los Angeles Times reported. They have to act fast, the California Department of Water Resources (DWR) warned: another storm is expected to hit Wednesday.

"The Oroville dam is one of thousands of aging dams whose problems probably should've been addressed before they pose an immediate threat to the surrounding community," Rowland added. 

California Gov. Jerry Brown said it was “clear the circumstances are complex and rapidly changing” in a press release Sunday. “I want to thank local and state law enforcement for leading evacuation efforts and doing their part to keep residents safe,” he added. Brown also issued an emergency order on Sunday in an effort to aid response teams on the ground.

Brown went on to add: “The state is directing all necessary personnel and resources to deal with this very serious situation.”