Will the Sacramento Delta Be the Next Massive Flood Disaster?

The rains have already started in California. The Golden State is prepped for an epic El Niño year. Ski slopes are opening weeks early. So is 2016 finally the year of the next great Sacramento Flood? ThinkProgress tackled this question a few month's ago and the answer they came up with wasn't pretty. Nationally, our critical levee infrastructure is in poor shape. A "report card" study from 2013 awarded the country a "D-". But Sacramento, with a unique confluence of high population density, agricultural importance, and seismic exposure, is probably the largest risk for massive flood damage in the country.

A 64 Percent Chance of Total Catastrophe

A leading expert in watershed management pegged the likelihood of a catastrophic flood in the Sacramento Delta at 64%. Today, more than two million people live in or around the Sacramento River Delta. Several of California's most important interstate highways run through the delta as do important rail lines. They are key transportation lines from the West Coast into the interior of the United States. Valleys around Sacramento, too, are among the most productive farmlands on the planet. And the Delta is a key provider of water to the fast-growing Bay Area cities of Oakland, San Francisco and San Jose.

Map: Levees That Failed Last Inspection As "Unacceptable" In the West

The risks of flooding have actually increased not only by the aging of levees, many of which are privately maintained, but also by impacts of water-table depletion and climate change. In some parts of the farming valleys around the Delta, overuse of groundwater has caused the water table to drop. This has, in turn, caused the land to sink each year. In some parts of the Delta, the farmland sits more than two-dozen feet below sea level. Equally troubling, rising sea levels have increased both the existing stress on the levee infrastructure but also upped the likelihood and potential severity of damage from storm surges.

From the Breadbasket to the Tech Hub, Everyone's At Risk

Robert Verchick, Gauthier-St. Martin Chair in Environmental Law at Loyola University New Orleans and a former EPA deputy associate administrator, told ThinkProgress, "Ruptures of the levees would swamp Sacramento and places like San Francisco wouldn't have water for weeks. That's what keeps me up at night, thinking about those kinds of problems."


This isn't the first time a major publication has dedicated ink to impending doom in the Sacramento Delta. A 2011 New York Times Magazine story called Sacramento "...the most flood-prone city in the nation." The article detailed the twin daggers poised to fall; either a violent rainstorm or a massive earthquake could cause widespread destruction of the earthworks, unleashing floods that cause billions and billions of dollars in damages - damages far in excess of those suffered by New Orleans and Louisiana from Hurricane Katrina.

After the disaster of Katrina, lawmakers recognized the level problem in the waiting. Congress launched a National Levee Safety Program to improve the levee system and accelerate inspections. State, local, and federal efforts to shore up Sacramento and the surrounding Delta. Regardless, the U.S. Army Corps of Engineers calls the Sacramento area, according to the ThinkProgress article, "among the most at-risk regions in America for catastrophic flooding."

Meanwhile, the Sierra Mountains are looking snowy white way earlier than normal. Scientists are calling the chance of a "Super Niño" year more and more likely. The Sacramento River Delta has survived numerous floods before. But will 2016 finally bring the Big One? We will soon find out.