California Dam Crisis Could Have Been Averted
A dismissed lawsuit to strengthen the dam because of climate change effects predicted catastrophic flooding
The menacing floodwaters last week forced the emergency evacuation of 188,000 residents. Yet the impending disaster came as no surprise to officials in Butte and Plumas counties. The rural counties, which surround Lake Oroville, had challenged the state’s environmental review of dam operations in a 2008 lawsuit, arguing the state "recklessly failed" to properly account for climate change in its long-term dam management plan.
The dam was built in the 1960s when temperatures were cooler and more precipitation was stored in a greater snowpack in the mountains of the Feather River watershed, which drains into Lake Oroville. Today warming temperatures are bringing more rain as well as melting the Sierra Nevada snowpack earlier in the spring. As the counties’ attorneys predicted, among the results is a rush of downhill water much faster than in the past. “We anticipated that this crisis might come about,” says Tony Rossmann, special counsel to Butte County.
That's exactly what happened a week ago, leading to the crater. With the reservoir brimming over from rain and rapid snowmelt, and the spillway maxed out as the crater widened, officials activated Oroville’s never-used unpaved emergency spillway—a broad hillside a short distance from the spillway along the same dam wall. The combination of rocks, trees and floodwaters pummeling down toward the cities below the dam forced the mandatory evacuations. Hard rain is happening again today as new storms continue to deluge the area 150 miles north of San Francisco.
Most of the nation’s 84,000 dams were built between 1950 and 1980 and were not designed for the populations now surrounding them, or for today’s changing climate. Nearly 3,000 have no emergency plans, a 2013
engineering report found.
Rossmann said dam managers throughout the West should be updating their scientific data to avoid crises similar to Oroville. “It’s irrational and risky to operate without considering modern” climate trends and the changes they could create in rainfall, snowpack, runoff and flooding, he says.
California Dam Crisis Could Have Been Averted