Topic: Levees

Overview

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 Santa Cruz Sentinel (Calif.)

Sen. John Laird introduces bill to speed up Pajaro River levee construction timelines

A state lawmaker has unveiled legislation designed to speed up the construction effort that will bring much-needed flood protection improvements to the Pajaro Valley. In the name of increased efficiency, California Sen. John Laird has introduced Senate Bill 1055, meant to expand the suite of contracting tools available to the Pajaro Regional Flood Management Agency. The local agency has been spearheading the ongoing overhaul of the Pajaro River levee system in South Santa Cruz County and North Monterey County alongside state and federal partners. … The bill would authorize the flood management agency to tap a number of additional contracting methods to maximize flexibility in order to accelerate construction timelines and reduce costs. 

Aquafornia news Bay City News Service

Down or up: Should a flood-prone stretch of highway become a tunnel or a bridge?

While regional agencies weigh a proposal to raise a floodprone stretch of U.S. Highway 101 between the Manzanita park-and-ride and Donahue Street in Marin County, a local scholar has explored an alternate vision: putting the freeway in a tunnel beneath a new linear park. The two views highlight the stakes for Marin City, a lowlying community that is already likened by experts to a bathtub with an inadequate drain as sea levels rise. There is currently a preliminary plan to elevate Highway 101 from Manzanita to Donahue at a rough estimate of $1.2 billion, with an extra $33 million for stormwater pumps and a drain pipe to carry rainwater beneath a shopping center that sits on slightly higher ground between Marin City’s entrance road and Richardson Bay.

Other flood planning news:

Aquafornia news CBS Sacramento (Calif.)

San Joaquin Area Flood Control Agency supports bill to repair levees in the delta

There’s been levee breaks over the years all over the delta, according to San Joaquin Area Flood Control Agency executive director Darren Suen. … Democratic state Senator Jerry McNerney introduced SB 872 that would direct $300 million annually in greenhouse gas reduction fund (GGRF) dollars to levee repairs in the delta and to shore up SWP’s canals to prevent interruptions in essential water deliveries. … The bill would include, according to Suen, fixing their levees to prevent subsidence and saltwater intrusion. … Suen also said these levied systems were started during the Gold Rush and a lot of them haven’t been maintained up to “federal standards.”

Other levee news:

Aquafornia news Monterey County Weekly (Seaside, Calif.)

Three years after the Pajaro River levee breached, rebuilding continues at a steady pace

It’s been three years since the Pajaro River levee crumbled and the river flooded the town of Pajaro, displacing hundreds of people and causing untold amounts of damage to homes and businesses. Decades in the making, a project to bolster the levee in Pajaro and Watsonville is at last expected to begin construction in earnest this week, but first in Watsonville. Pajaro residents will have to spend a few more winters with the current levee, as the portion that breached and was repaired in 2023 may not begin construction until 2029 or 2030. … The cost of the $599 million project is shared by the state and federal government.

Aquafornia news KTVU/FOX2 (Oakland, Calif.)

Marin County flood control projects suspended

As Marin County wrestles with coastal flooding, king tides and federal bureaucracy, two significant flood control projects are suspended and they won’t be restarted until the county can figure out how to balance all the interests. … In early January, Marin County had multiple low-lying area floods. Though it’s not the first time, Marin is becoming an early model for what will impact other bay side and seaside communities as sea level rises, flooding other areas. … A flood control project to lessen or eliminate flooding here is now on hold by the county after FEMA, the Federal Emergency Management Agency, said work here could flood other locales further downstream. 

Other flood control news:

Aquafornia news The Sacramento Bee (Calif.)

Opinion: How the 1986 flood reshaped Sacramento flood protection

… The fear of flooding has steadily faded in Sacramento because of what happened after the great storms of 1986. Sacramento came together and created flood control protections, arguably the most effective regional government effort in local history. And now, some $5 billion in flood protection improvements later, Sacramento is almost ready for much bigger storms. Still, this region does not take flooding as seriously as it should. Public attention is far more focused on how a warming climate increases the risk of wildfires and heat waves. But hotter temperatures are also creating more vapor in the atmosphere, a flood waiting to happen.
–Written by Sacramento Bee columnist Tom Philp.

Related article:

Aquafornia news The Pajaronian (Watsonville, Calif.)

Padilla, Schiff secure $54M for Pajaro River Levee

U.S. Sen. Alex Padilla announced Tuesday that he and Sen. Adam Schiff secured $54 million in federal funding for the Pajaro River Flood Risk Management Project, aimed at strengthening flood protection for Watsonville and Pajaro. The funding will go toward reconstructing failing levees along the Pajaro River and its tributaries in Monterey and Santa Cruz counties, according to Padilla’s office. The project is intended to reduce flood risk for residents, businesses and infrastructure in the low-lying communities. … Problems with the aging levee have plagued the region for years, overtopping its banks and allowing devastating floods in 1955, 1995 and 1997. Some 3,000 properties lie in the floodplain.

Other flood infrastructure news:

Publication Sacramento-San Joaquin Delta Map

Layperson’s Guide to the Delta
Updated 2025

Image shows the cover of the Layperson's Guide to the Sacramento-San Joaquin Delta.

The 24-page Layperson’s Guide to the Delta explores the competing uses and demands on California’s Sacramento-San Joaquin Delta. The 11th edition examines this critical water hub and its myriad challenges. The 2025 version includes the latest information on the tunnel project, habitat restoration efforts, climate change impacts and an updated section on the legal and political facets of the Delta.

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.

Video

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.

Publication

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.

The State Water Project is best known for the 444-mile-long aqueduct that provides water from the Delta to San Joaquin Valley agriculture and southern California cities. The guide contains information about the project’s history and facilities.

Publication

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. 

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

Restored floodplain at Dos Rios Ranch Preserve near Modesto

With the dual threats of aging levees and anticipated rising sea levels, floodplains — low areas along 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

Levees

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.

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.