In midst of drought, Sacramento needs to prepare for flood
El Niño events are characterized by a prolonged warming of waters in the Pacific and strong trade winds that lead to dry winters in much of the United States and a downright diluvial season in California. The last time this type of system struck Norther California in a meaningful way was in 1997.
That year, residents throughout the region were swamped by floodwaters that broke levies and damaged infrastructure. Olivehurst, Arboga, Wilton, Manteca and Modesto all flooded to varying degrees, as the Consumnes River surged. Through sheer fortune, Sacramento itself was spared from a watery fate. There is no guarantee such luck will befall the Sacramento area again.
The “River City” rests at the confluence of the American and Sacramento Rivers, precisely where they enter the delta. The city has a history of flooding that dates back to its formation. In fact, Gov. Leland Stanford traveled to his 1862 inauguration not by horse or carriage, but rather, by boat.
While Sacramento’s geographic situation hasn’t changed since 1997, development in the area has. Sacramento proper has grown by 80,000 residents in the last 18 years. The northern Sacramento suburb of Natomas was, until a 2008 moratorium, the largest driver of the city’s growth. Much to the surprise of many of its new residents, Natomas is built – literally – in an area once designated the “Natomas flood-basin.” Meanwhile, West Sacramento has grown by 20,000 people – nearly 40 percent.
All of this growth has been a boon to the region’s economy, but left it vulnerable to extreme weather events. In spite of concerted efforts to strengthen flood-protection mechanisms, by all accounts, the frequency, intensity and severity of extreme weather events is on the rise. Barriers meant for 1-in- 500 year storms may be rendered redundant, as those storms become 1-in-100-year events. Compounding that vulnerability is the specter of a temblor of even middling severity that could breach newly bolstered defensive barriers and cause damage even without a storm.
To-date, the city has proceeded as though concern is unwarranted. In March, the City Council approved construction of 1,500 new homes in Natomas.
Residents and voters should be mindful of the fact that electoral time horizons do not correspond to natural time horizons. A politician elected today who places the city at risk for a catastrophic flood 50 years from now accrues immediate benefits without experiencing any near-term costs.
The remedy to the risks that Sacramento faces is not federally built levies, nor is it federally subsidized flood insurance. Instead, the solution is to show the restraint necessary to say no to further development in high-risk areas. When Sacramento next floods, and it will, the harm to the city could be comparable to that other seriously flood-prone metropolis: New Orleans.