One Month Later, Is the Oroville Dam Safe for California Residents?

The last few months have seen heavy rainfall in the Golden State, which could spell trouble for California’s dams.

Jinder Dhanota was finishing up some work at home on Sunday evening when he received the emergency alert on his phone. Within an hour, his wife rushed home from work. They packed what they could for themselves and their toddler to head out of Yuba City. The roads were packed and it took them almost two hours to reach safety at Dhanota’s sister’s home.

“We weren’t even sure if we were going to be able to get out of Yuba City on time,” says Dhanota, a 35-year-old business owner. “I felt a lot of anger. They waited till about 4 p.m. to let us know about the emergency spillway failing. Who knows what could’ve happened if that would’ve failed? Who knows how many people would’ve died?”

A gash was discovered in Oroville Dam’s main concrete spillway on February 7th. After finding the gash, officials decided to continue using the main spillway, though at reduced capacity. Water began flowing into the emergency spillways, causing erosion in the hillside below the emergency spillway wall. If the wall gave way, a 30-foot-high flood of water would be unleashed onto the residents below.

This erosion placed downstream residents in neighboring counties at risk, and by the evening of Sunday, February 12th, more than 180,000 residents were forced to evacuate from the Central Valley’s Butte, Sutter, and Yuba Counties.

Residents were allowed to return the following Tuesday, but, four weeks later, concern over the dam — and the state of California infrastructure at large — remains at the forefront of residents’ minds.

“Everybody is still worried about the dam,” Dhanota says. “Is that dam going to be able to handle the next storm that comes in, or will we be in the same situation as a few weeks ago?”

On Tuesday, February 14th, the evacuation mandate changed to an evacuation warning. Butte County officials will not lift the evacuation warning until the area in front of the emergency spillway is fortified, the water level at Lake Oroville is reduced, and the Hyatt power plant — as a means to lower water levels — is up and running. Efforts to fortify the emergency spillways are now underway.

“People still need to be vigilant. It’s a very dynamic situation and Mother Nature doesn’t always decide to coordinate with us,” says Chris Orrock, a public information officer at the California Department of Water Resources (DWR).

Mother Nature doesn’t seem to be letting up an anytime soon. So what does that mean for California residents?

This isn’t the first time the Oroville Dam’s spillways have been called into question.

In 2001, three environmental groups, including Sacramento-based non-profit Friends of the River, urged DWR to fortify Oroville dam’s emergency spillway, doubting the spillway’s ability to withstand heavy water flow.

“Basically we said, ‘look, it’s an inherently unsafe design and it’ll cause havoc when you use it,’” says Ron Stork, policy director at Friends of the River.

Though DWR and the environmental groups remained in talks over the concerns for years, no action was ultimately taken.

“Mother Nature doesn’t always decide to coordinate with us.”

In 2005, the groups filed a motion with the Federal Energy Regulatory Commission as the Oroville Dam underwent a re-licensing process, asking the commission to require state officials to fortify the spillway with concrete. Without this concrete, the hillside could wash away and flood nearby regions, they argued.

FERC officials did not see the concerns.

“It is important to recognize that, during a rare event with the emergency spillway flowing at its design capacity, spillway operations would not affect reservoir control or endanger the dam,” wrote John Onderdonk, a senior civil engineer with FERC, in a 2006 memo to his managers.

The commission ultimately rejected the request.

“We got significant push back from the Department [of Water and Resources] and state water contractors. They didn’t think they would ever need to use the emergency spillway,” Stork says. “This demonstrated to be very wrong.”

Now, state officials are assuring residents the safety of the dam moving forward.

“We have crews out there 24 hours a day moving rocks, gravel, and sand and solidifying that into the eroded areas with cement,” Orrock says. “We’re going to continue to make safety a priority.”

Deputy Director of Communications at the California Natural Resources Agency Nancy Vogel stressed the overall security of the dam. In addition to annual inspections of the dam, an independent consultant reviews and inspects the dam every four years, she explains.

“Oroville Dam is safe. The spillways are separate structures. In its 48 years, the emergency spillways have never been used before and the emergency spillways would not have been used at all if it weren’t for the sudden erosion in the dam’s main spillway,” Vogel says.

Oroville Dam is one of many dams across California requiring greater attention: According to a report by the Department of Water Resources and the Army Corps of Engineers, $50 billion in flood control projects are required across the state, such as improving the Sacramento-San Joaquin River Delta’s levees and improving the state’s flood management systems.

Federal investment in infrastructure, such as dams, however, has fallen by half in the last 35 years, once accounting for 1 percent of the gross domestic product, now only 0.5 percent.

California has attempted to mitigate that decline in infrastructure through Governor Jerry Brown’s 2016 Five Year Infrastructure Plan.

The plan proposed a $55 billion investment in infrastructure over the next five years. However, the majority of these funds were allocated toward public transit, and not water structures: Thirty-six billion of the total $55 billion plan is directed toward highways and roads.

“The needs of California infrastructure are great and the plan was not comprehensive. There are a lot of infrastructure needs in California and there’s no end-all-be-all list to fix it,” Vogel says.

At a press conference last week, Brown proposed a four-point plan to further address flood protection and dam safety. He is seeking a $437 million investment for flood control and emergency response actions. Fifty million dollars will come from the state’s general fund and $387 million will come from Proposition 1 funds.

In addition to this, Brown is requiring emergency action plans for all dams in the state, an enhanced dam inspection program, and seeking increased funding from the federal government for dam safety.

“Recent storms have pounded the state of California, resulting in a dam spillway eroding, roads crumbling and levees failing,” Brown said. “Our aging infrastructure is maxed out. We can take some immediate actions, and we will, but going forward we’ll need billions more in investment.”

Brown sent a letter to the federal government requesting further funds to assist in the rehabilitation of California’s dams and flood safety efforts. No specific dollar amount is attached to this request.

The Water Infrastructure Improvement for the Nation Act, passed in Congress last year, offers potential solutions. The act, sponsored by Senator John Corryn (R-Texas) and passed with bipartisan support, authorizes $445 million over 10 years to rehabilitate non-federal dams, such as Oroville. The act also approves spending on further flood-safety efforts, including storm water management programs and rehabilitation of levees.

The act still needs to be appropriated for funding, however. For residents like Dhanota, that investment cannot happen quickly enough.

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