Topic: Levees



California would not exist as it does today were it not for the extensive system of levees, weirs and flood bypasses that have been built through the years, particularly in the Sacramento-San Joaquin Delta.

Aquafornia news Los Angeles Times

Thursday Top of the Scroll: How powerful land barons shaped the epic floods in California’s Central Valley

In most parts of California, and indeed the United States, the idea that the government would largely cede to private companies management of a natural disaster that could decimate multiple towns, displace thousands of farmworkers and wreak destruction across hundreds of square miles would be unfathomable. But that has long been how things operate in the Tulare Lake Basin. Land barons, chief among them J.G. Boswell’s founder, seized control of the basin and its water generations ago and have since managed it with minimal government interference. … The flood-prone Tulare Lake Basin is the one part of the Central Valley that has a special exemption from state-required flood control plans, leaving the area without a clear public strategy for managing floodwaters.

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Aquafornia news Marin Independent Journal

Editorial: Santa Venetia flood-control berms should be built to last

There’s no debate whether flooding is a serious risk for Santa Venetia residents. … the county has started work on repairing sections of the timber-reinforced earth berm that is now protecting the area. … The wall, stretching from Meadow Drive to Vendola Drive, is deteriorating. The county is spending $300,000 to repair it. The plan is to finish the work by the end of October, in time to upgrade protection before the rainy season.

Aquafornia news KQED - San Francisco

Listen: Pajaro residents know permanent fix for levees is still a long way away

It’s been six months since the levee protecting the small Central Coast farming community of Pajaro burst, flooding the town and forcing thousands out of their homes. And while repairs are underway, a permanent fix is still years in the making.

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Aquafornia news The New York Times

Opinion: Libya showed what happens if we ignore aging dams

The collapse of two dams in Libya, unleashing torrential floodwaters that left at least 3,000 people dead and over 4,200 still missing, was both predicted and preventable. And they won’t be the last big dams to collapse … In the United States, the second most prolific dam-builder after China, the average age of dams is 65 years old and an estimated 2,200 structures are at high risk of collapse. … The fact that it’s increasingly difficult to justify many dams’ existence is one reason there is a growing movement, often led by Indigenous peoples and other marginalized populations, to remove them. Most notably, the removal of four dams on the Klamath River along the Oregon-California border, set to be completed next year, will be the largest such effort in history.
-Written by Josh Klemm and Isabella Winkler, co-directors of International Rivers, a group that advocates for healthy rivers and the rights of river communities.

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Aquafornia news The Sacramento Bee

City of Sacramento plans maintenance on flood infrastructure

Last winter, Sacramento faced a three-week series of atmospheric rivers that brought flooding across the Valley and downed trees and branches. As the region gets closer to another rainy season, Sacramento’s utility department is preparing by shoring up critical flood control infrastructure across the city. The maintenance is similar to work done in years past, according to a news release, and to work done in March. Work will begin Sept. 18 at a ditch near Winters Street, before moving to Strawberry Creek, the 5-B detention basin in North Natomas, Lower and Upper Morrison creeks and ditches near the Sacramento Northern Bike Trail.

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Aquafornia news Monterey County Weekly

Neglected for decades, the Pajaro levee is finally holding attention of policymakers

On an overcast morning on Friday, Aug. 25, as jets of water from sprinklers rain down on the surrounding fields of lettuce, a gaggle of journalists, politicians and public officials are gathered at a press event along the Pajaro River levee, just more than a stone’s throw from where it breached last March. The breach occurred after weeks of sustained rainfall on the Central Coast, and it wasn’t a surprise – for over 50 years, federal, state and local officials have known the levee was deficient, but there was never enough buy-in, or urgency, to do something about it. Seemingly, that is starting to change, but time will tell if it’s real, or just a public relations band-aid to save face after the flooding in the community of Pajaro, which displaced thousands of residents from their homes and left some of those homes unlivable.

Aquafornia news SJV Water

Planning and luck kept Kern County’s flood-prone Lamont mostly dry this year

Of all the places that unexpectedly flooded this past year, there was one that unexpectedly did not – Lamont. Typically, heavy rain years kick up water in the Caliente Creek and it comes rushing east out of the Tehachapi Mountains, turns south under Highway 58 into a wide wash and floods out Lamont. Years ago, the water would have spread out like a sheet and continued south toward Arvin. But farmers built a levee along Mountain View Road and lined it with tamarisk trees. The structure is easily spotted on satellite map views of the area.

Aquafornia news Lookout Local Santa Cruz

As Pajaro River levee repairs begin, questions remain around the long-sought replacement

About a half-mile off San Juan Road, past the lettuce fields, excavators and tractors have begun moving earth to repair the exact spot along the 12-mile Pajaro River levee that failed on March 11, leading to catastrophic flooding and generational disaster. Elected officials and community leaders from Santa Cruz and Monterey counties and representatives from the U.S. Army Corps of Engineers stood against a noisy backdrop of construction Friday to update the community on where this urgent project stands. The emergency repair underway will focus on three sections of the levee. The first section, where the levee burst in March, will finish by Nov. 2, according to Holly Costa, emergency management chief for the corps.

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Aquafornia news Santa Cruz Local

Months after Pajaro flood, repair crews race against winter rain

Nearly six months after a Pajaro River levee breach upended the lives of about 3,000 Pajaro residents, the U.S. Army Corps of Engineers is trying to complete repairs on three parts of the levee before anticipated winter rain. Emergency repairs are expected to finish by the end of November but it could take longer if there is rain, said Holly Costa, emergency management chief for the Army Corps of Engineers. It is “very unusual” for levees to be fully repaired in the same year they were damaged, Costa said. When the levee was damaged in the past, “we didn’t get those repaired until two or three years afterwards,” she said. Completing the levee repairs before the rainy season is crucial because wet conditions could make the work difficult, Costa said.

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Aquafornia news Oroville Mercury-Register

Butte County supervisors to discuss potential flood risk study

The Butte County Board of Supervisors will be returning to talks regarding a potential Flood Risk Reduction Feasibility Study on Tuesday based on data gathered by its Public Works Department. Stemming from discussions in both 2020 and 2021, the public works staff was given direction by the board to work with field experts and stakeholders to come up with a draft study regarding Nord, Rock Creek and Keefer Slough. According to the related agenda item, a presentation is planned for Tuesday’s meeting that will go over the draft study, its findings and what measures are possible for the county in reducing the risk for these areas.

California Spent Decades Trying to Keep Central Valley Floods at Bay. Now It Looks to Welcome Them Back
WESTERN WATER IN-DEPTH: Floodplain restoration gets a policy and funding boost as interest grows in projects that bring multiple benefits to respond to climate change impacts

Land and waterway managers labored hard over the course of a century to control California’s unruly rivers by building dams and levees to slow and contain their water. Now, farmers, environmentalists and agencies are undoing some of that work as part of an accelerating campaign to restore the state’s major floodplains.

Tour Nick Gray Jenn Bowles Layperson's Guide to the Delta

Bay-Delta Tour 2021
A Virtual Journey - September 9

This tour guided participants on a virtual journey deep into California’s most crucial water and ecological resource – the Sacramento-San Joaquin Delta. The 720,000-acre network of islands and canals support the state’s two major water systems – the State Water Project and the Central Valley Project. The Delta and the connecting San Francisco Bay form the largest freshwater tidal estuary of its kind on the West coast.

Western Water California Water Map Gary Pitzer

Can a New Approach to Managing California Reservoirs Save Water and Still Protect Against Floods?
WESTERN WATER NOTEBOOK: Pilot Projects Testing Viability of Using Improved Forecasting to Guide Reservoir Operations

Bullards Bar Dam spills water during 2017 atmospheric river storms.Many of California’s watersheds are notoriously flashy – swerving from below-average flows to jarring flood conditions in quick order. The state needs all the water it can get from storms, but current flood management guidelines are strict and unyielding, requiring reservoirs to dump water each winter to make space for flood flows that may not come.

However, new tools and operating methods are emerging that could lead the way to a redefined system that improves both water supply and flood protection capabilities.

Western Water California Water Map Gary Pitzer

When Water Worries Often Pit Farms vs. Fish, a Sacramento Valley Farm Is Trying To Address The Needs Of Both
WESTERN WATER SPOTLIGHT: River Garden Farms is piloting projects that could add habitat and food to aid Sacramento River salmon

Roger Cornwell, general manager of River Garden Farms, with an example of a refuge like the ones that were lowered into the Sacramento River at Redding to shelter juvenile salmon.  Farmers in the Central Valley are broiling about California’s plan to increase flows in the Sacramento and San Joaquin river systems to help struggling salmon runs avoid extinction. But in one corner of the fertile breadbasket, River Garden Farms is taking part in some extraordinary efforts to provide the embattled fish with refuge from predators and enough food to eat.

And while there is no direct benefit to one farm’s voluntary actions, the belief is what’s good for the fish is good for the farmers.

Western Water Layperson's Guide to the Delta

ON THE ROAD: Park Near Historic Levee Rupture Offers Glimpse of Old Sacramento-San Joaquin Delta
Big Break Regional Shoreline will be a stop on Bay-Delta Tour May 16-18

Visitors explore a large, three-dimensional map of the Sacramento-San Joaquin Delta at Big Break Regional Shoreline in Oakley. Along the banks of the Sacramento-San Joaquin Delta in Oakley, about 50 miles southwest of Sacramento, is a park that harkens back to the days when the Delta lured Native Americans, Spanish explorers, French fur trappers, and later farmers to its abundant wildlife and rich soil.

That historical Delta was an enormous marsh linked to the two freshwater rivers entering from the north and south, and tidal flows coming from the San Francisco Bay. After the Gold Rush, settlers began building levees and farms, changing the landscape and altering the habitat.


Delta Warning

15-minute DVD that graphically portrays the potential disaster should a major earthquake hit the Sacramento-San Joaquin Delta. “Delta Warning” depicts what would happen in the event of an earthquake registering 6.5 on the Richter scale: 30 levee breaks, 16 flooded islands and a 300 billion gallon intrusion of salt water from the Bay – the “big gulp” – which would shut down the State Water Project and Central Valley Project pumping plants.


Layperson’s Guide to the State Water Project
Updated 2013

The 24-page Layperson’s Guide to the State Water Project provides an overview of the California-funded and constructed State Water Project.


Layperson’s Guide to Flood Management
Updated 2009

The 24-page Layperson’s Guide to Flood Management explains the physical flood control system, including levees; discusses previous flood events (including the 1997 flooding); explores issues of floodplain management and development; provides an overview of flood forecasting; and outlines ongoing flood control projects. 

Publication Sacramento-San Joaquin Delta Map

Layperson’s Guide to the Delta
Updated 2020

The 24-page Layperson’s Guide to the Delta explores the competing uses and demands on California’s Sacramento-San Joaquin Delta. Included in the guide are sections on the history of the Delta, its role in the state’s water system, and its many complex issues with sections on water quality, levees, salinity and agricultural drainage, fish and wildlife, and water distribution.

Maps & Posters California Water Bundle

California Water Map
Updated December 2016

A new look for our most popular product! And it’s the perfect gift for the water wonk in your life.

Our 24×36 inch California Water Map is widely known for being the definitive poster that shows the integral role water plays in the state. On this updated version, it is easier to see California’s natural waterways and man-made reservoirs and aqueducts – including federally, state and locally funded projects – the wild and scenic rivers system, and natural lakes. The map features beautiful photos of California’s natural environment, rivers, water projects, wildlife, and urban and agricultural uses and the text focuses on key issues: water supply, water use, water projects, the Delta, wild and scenic rivers and the Colorado River.

Floodplains in California

With the dual threats of obsolete levees and anticipated rising sea levels, floodplains—low areas adjacent to waterways that flood during wet years—are increasingly at the forefront of many public policy and water issues in California.

Adding to the challenges, many floodplains have been heavily developed and are home to major cities such as Sacramento. Large parts of California’s valleys are historic floodplains as well.

Aquapedia background

Sacramento-San Joaquin Delta Levees

Sacramento-San Joaquin Delta Levees

Roughly 1,115 miles of levees protect farms, cities, schools and people in and around the Sacramento-San Joaquin Delta, a crucial conduit for California’s overall water supply. But the Delta’s levees are vulnerable to failure due to floods, earthquakes and rising sea levels brought about by climate change. A widespread failure could imperil the state’s water supply.

Aquapedia background



California would not exist as it does today were it not for the extensive system of levees, weirs and flood bypasses that have been built through the years, particularly in the Sacramento-San Joaquin Delta.

These levees have been in place dating back to 1850, when California first joined the union.

Western Water Magazine

Meeting the Co-equal Goals? The Bay Delta Conservation Plan
May/June 2013

This issue of Western Water looks at the BDCP and the Coalition to Support Delta Projects, issues that are aimed at improving the health and safety of the Delta while solidifying California’s long-term water supply reliability.

Western Water Magazine

How Much Water Does the Delta Need?
July/August 2012

This printed issue of Western Water examines the issues associated with the State Water Board’s proposed revision of the water quality Bay-Delta Plan, most notably the question of whether additional flows are needed for the system, and how they might be provided.

Western Water Magazine

Levees and Flood Protection: A Shared Responsibility
May/June 2012

This printed issue of Western Water discusses several flood-related issues, including the proposed Central Valley Flood Protection Plan, the FEMA remapping process and the dispute between the state and the Corps regarding the levee vegetation policy.

Western Water Excerpt Gary PitzerRita Schmidt Sudman

Levees and Flood Protections: A Shared Responsibility
May/June 2012

Levees are one of those pieces of engineering that are never really appreciated until they fail. California would not exist as it does today were it not for the extensive system of levees, weirs and flood bypasses that have been built through the years.

Western Water Magazine

Finding a Vision for the Delta
March/April 2008

This printed copy of Western Water examines the Delta through the many ongoing activities focusing on it, most notably the Delta Vision process. Many hours of testimony, research, legal proceedings, public hearings and discussion have occurred and will continue as the state seeks the ultimate solution to the problems tied to the Delta.

Western Water Magazine

A Significant Challenge: Adapting Water Management to Climate Change
January/February 2008

This printed copy of Western Water examines climate change – what’s known about it, the remaining uncertainty and what steps water agencies are talking to prepare for its impact. Much of the information comes from the October 2007 California Climate Change and Water Adaptation Summit sponsored by the Water Education Foundation and DWR and the November 2007 California Water Policy Conference sponsored by Public Officials for Water and Environmental Reform.

Western Water Magazine

It Can Happen Here: Assessing California’s Flood Risk
November/December 2005

This issue of Western Water examines the extent to which California faces a disaster equal to or greater than the New Orleans floods and the steps being taken to recognize and address the shortcomings of the flood control system in the Central Valley and the Delta, which is of critical importance because of its role in providing water to 22 million people. Complicating matters are the state’s skyrocketing pace of growth coupled with an inherently difficult process of obtaining secure, long-term funds for levee repairs and continued maintenance.

Western Water Magazine

Flood Management 2004: A System in Peril
September/October 2004

This issue of Western Water analyzes northern California’s extensive flood control system – it’ history, current concerns, the Paterno decision and how experts are re-thinking the concept of flood management.