California’s Water: Drought, Floods And Preparedness
Mark Cowin is director of the California Department of Water Resources and can be reached at Mark.Cowin@water.ca.gov.
In every season of each year, Californians think about water — we need to be careful about how we use it and ready for its potentially destructive power.
California’s 38 million people and its industry and agriculture depend largely upon five or six storms each winter to generate its water supply. When storms fail to materialize for more than a couple of years in a row, we suffer drought. When storms roll in from the Pacific Ocean that are stronger or faster than our infrastructure can handle, we risk the effects of flooding.
State and local government leaders and every Californian should be prepared for drought and floods. In any given year, we may get either — or both.
Climate experts tell us the strong El Niño conditions in the Pacific Ocean give us higher odds of heavy precipitation this winter, especially in Southern and Central California. Even before winter began, localized downpours in Los Angeles and Kern counties buried hundreds of cars and trucks in mud and forced the closure of Interstate 5 for days in October. Downpours may bring flooding this winter and yet still not refill our reservoirs, build the mountain snowpack or recharge aquifers adequately to end the drought. It will take a few years of above-average precipitation to eliminate the water deficit of the drought, and we may get one wet year followed by more dry years.
Preparedness Is Essential
Voters passed a $4 billion disaster preparedness and flood control bond in 2006, Proposition 1E, that has allowed the state to help local agencies protect homes and lives from levee failures, flash floods and mud slides. Prop. 84, also passed by voters in 2006, included $800 million for flood control. Those bond dollars have been put to work on hundreds of safeguarding projects, including strengthening the levees that protect Central Valley cities, replacing a 114-year-old dam in Escondido, building stormwater detention basins that improve flood control and naturally treat urban runoff, and constructing a 5-mile pipeline that will enable Los Angeles County to use stormwater to recharge a groundwater basin.
Managing Our Most Precious Natural Resource
When this winter began, Northern California’s major reservoirs were generally one-third to one-half as full as the historical average. So although we have millions of acre-feet of empty space behind dams to capture storm runoff and snowmelt, that space cannot protect Californians against levee breaks, mudslides or overflowing urban creeks.
Managing water in California to avoid both flooding and supply shortages is a never-ending job that grows more complicated with climate change. It requires steady investment in the infrastructure that allows us to recycle, recharge, restore, conserve, capture and move water. In the past four years, the California Department of Water Resources has awarded $577 million in integrated regional water management grant funds to leverage over $2.1 billion of local investment in more than 450 priority projects; these efforts will enhance California’s water supply by about 2 million acre-feet annually. That’s enough water to supply 4 million typical households for a year.
Prop. 1, the water bond approved by voters in 2014, will maintain our momentum on these multibenefit projects that help build regional self-sufficiency. We cannot make California entirely drought- or flood-proof. But with steady investment and preparation, we can avoid the worst effects of both drought and floods.