After the Deluge

In the wake of this century's greatest flooding, California looks ahead to preventing a future catastrophe.

Late December's and early January's flooding was the most widespread in California's history. A series of storms roared across the eastern Pacific bringing more rain and snow during those two months than any other similar period in this century.

A subtropical "Pineapple Express" packed the greatest punch, overwhelming the capacity of some reservoirs and levees to hold back the flow. In dozens of places, levees in the Central Valley became saturated and crumbled. Eight people died, hundreds were injured, and more than 100,000 left temporarily homeless. Damage was recorded in 48 of the state's 58 counties. About 300 square miles of farmland and residential and commercial property were inundated. Estimates of damage total $2 billion, including $300 million to the levee system.

If not for an extremely dry February, March, and April, substantial areas of the Central Valley would have stayed flooded or endangered well into the spring. Normally, the reservoirs on the San Joaquin River's tributaries act as catch basins for snowmelt runoff in the spring. When the rains stopped at the end of January, they were nearly full, requiring large releases downstream.

For the most part, the Central Valley flood control system -- considered one of the most comprehensive and highly engineered systems in the world -- performed well, according to the Corps of Engineers. Reservoirs remained intact and in all cases reduced record inflows which in turn lowered flood crests. But the system was significantly weakened. In many streams and rivers, flows exceeded the 1-in-100-year event often used by local community planners as a design threshold for urban flood control systems. (With this design threshold in place, residents are not required to purchase flood insurance.)

Colonel Peixotto of the Corps estimates that the system prevented more than $10 billion in additional flood damage and, more importantly, significantly reduced the scope of human suffering during and after the January storms. But this provides little consolation to those who suffered losses and no guarantees that the next flood will bring less destruction.

To find solutions that would reduce damage caused by future flooding, Governor Wilson has endorsed a series of recommendations by the Flood Emergency Action Team he named in January to investigate and report on short-range and long range solutions. Understanding these recommendations involves a brief review of the nature of the Central Valley and its potential for flooding.

A Valley Vulnerable to Flooding
Although many areas throughout California flooded during December and January, the Central Valley was hardest hit. The valley--California's agricultural heartland--drains nearly 40 percent of the state's surface area and covers almost 60,000 square miles.

Historians have documented frequent floods in the Central Valley. Among the earliest Valley explorers, Ensign Gabriel Moraga of Spain in 1808 noted signs of annual flooding. Prior to the arrival of European settlers, Indian tribes inhabiting the Central Valley were accustomed to periodic, seasonal flooding from winter rains and spring snowmelt.

In describing the flood scene, historian Robert Kelley wrote that the Valley floodwaters "ponded to form an immense, quiet inland sea, a hundred miles long ... its still masses of tule rushes stretching from the delta to the Sutter Buttes and beyond."

After the Gold Rush brought increasing settlement to California, major floods in 1850, 1853 and during the 1860s served notice of the chronic danger from floods to human habitation of the Valley floodplains.

But the potential use of the area for agriculture and, to some extent for urban settlement, was too valuable to be interrupted by flooding every few years. So the settlers began building levees and eventually floodways to convey floodwaters away from their property. Efforts to control the rivers continued for the next century.

In most years, floodwaters were contained or reduced by flood control systems. However, rivers are not static and where land is available at reasonable cost, leaving room for a river to migrate proved a wise move.

"It's important to recognize that we don't have the luxury of starting over from a natural system," says Maurice Roos, DWR's Chief Hydrologist and a lifelong Valley resident. "With around six million people living in the Central Valley, we have to do the best job possible of going forward from where we are now to find viable flood control solutions to protect life and property."

The Work of the Flood Emergency Action Team
Responding to concerns raised by the 1997 flooding, the Governor formed the Flood Emergency Action Team. In January, the Governor named 11 members of his Administration to the Team (known as FEAT) to coordinate state response to immediate problems, including levee repairs and other improvements to the flood control system. Chaired by Resources Secretary Douglas Wheeler, FEAT convened public meetings in areas where flooding occurred and listened to the opinions of hundreds of Californians.

FEAT had two responsibilities: prevent further loss of life and property and report to the Governor on immediate and long-term measures to change the situation for the better.

Thirty days after it was established, FEAT issued a report calling for further repairs of broken levees to provide greater protection, installation of additional real time sensors on rivers and reservoirs, pump-out of flooded lands, and more extensive study of the river systems prone to flooding.

To tackle levee repairs, the Corps of Engineers, assisted by DWR's newly created Levee Rehabilitation Unit, aggressively pursued numerous projects to repair levee breaks, providing interim flood protection for the remainder of the storm season. Fortunately, their task was aided by the driest late winter and spring on record. Currently, the State and the Corps are working to complete rehabilitation projects throughout the Central Valley before the next flood season.

The Corps' workload includes strengthening weak sections of levees and installing gravel "ballast berms" (to filter any water that seeps through the levee to prevent underground erosion of levee and foundation material). Wave-damaged areas, not fixed during the first round of emergency repairs in January, will also be repaired.

To return flooded farmland to production, DWR completed a program to assist local reclamation districts in pumping standing water out of some 80,000 acres of fields in the Central Valley. With the Corps and the U.S. Geological Survey, the Department also began installing added telemetry on unmonitored streams, increasing the ability of river forecasters to issue better warnings to levee districts and emergency evacuation authorities. Information from major streams is available online through the California Data Exchange Center operated by DWR. The Governor recommended funding increases for flood forecasting, telemetry maintenance, and data collection to further improve the flood data network.

In the long run, much more work needs to be done.

"The system has to be revised," says FEAT chairman Wheeler. "How we rebuild it is the critical issue for the next period in our response to these floods."

What FEAT Recommends
That period began at a June 6 news conference, where Governor Wilson announced FEAT's release of its final 289-page report. The Governor endorsed all recommendations and signed two executive orders immediately implementing many actions.

Arranged in four categories (emergency response, floodplain management, flood control system restoration and improvement, and further studies), the 65 recommendations cover the gamut of flood responsibilities of local, state and federal governments.

"To provide inoculation against the next round of storms," the Governor called for $31 million in the state budget over the next two fiscal years to pay for a number of flood-related projects, such as levee work on the Sacramento and American rivers and a comprehensive four-year watershed review of the Sacramento and San Joaquin river basins by the Corps of Engineers and the State. This will help determine additional improvements needed for the Sacramento and San Joaquin flood-control systems, an evaluation that was last done in 1910 on the Sacramento system.

Also included in the proposal is $2 million for restoration of a subsided reach of the Eastside Bypass on the lower San Joaquin River that local, state and federal water management experts have urged. The comprehensive study will look into alternatives on the lower San Joaquin River like the bypass system on the Sacramento River.

By Executive Order, the Governor created a State Floodplain Management Task Force, composed of representatives of state agencies to provide recommendations for additional floodplain management improvements by March 1, 1998. As the San Francisco Chronicle noted, what is built in floodplains is "the most politically sensitive issue," involving concerns of local control over development.

The floodplain task force has several specific charges:

- examine state and federal floodplain management regulations;

- identify changes to assist the State Reclamation Board in dealing with Central Valley flood management needs (The Board is responsible for overseeing state flood control activities in the Central Valley.);

- consider requiring future urban development to exceed minimum National Flood Insurance Program floodplain management elevation requirements;

- study flood insurance requirements for structures not protected to the 200 year level (Currently 100-year level protection is the threshold.);

- develop proactive non-structural floodplain management strategies;

- evaluate land-use policies; and

- determine the state's role in encouraging higher levels of floodplain management in conjunction with assisting local communities in funding flood control facilities.

In response to questions about what kinds of floodplain improvements will eventually be made, the Governor said there is a need for a mix of solutions, both structural and nonstructural. He cautioned that "no one size fits all" when it comes to floodplain management and that undeveloped floodplains are a big issue in which rights of property owners need to be reconciled with public safety. Most local government agencies, however, do not allow development directly in floodplains.

"We can't control what Mother Nature has in store for us," the Governor said. "But we can take decisive steps to ensure that we're not left out in the rain, the next time these storms reach our shores."

Restoration and Improvements
Other FEAT recommendations for restoring and improving the flood control system include:

- Federal acquisition of 3,000 acres of flood-prone lands in Stanislaus County. This would expand the San Joaquin National Wildlife Refuge and support ecosystem restoration goals of the CALFED Bay-Delta Program, the joint effort toward a long-term plan to "fix" the San Francisco Bay Delta.

- Assistance by the California Department of Fish and Game to private and public agencies for levee and river channel maintenance by providing biological and wildlife information necessary to secure federal approvals.

- Additional funding to the State Reclamation Board for the Sacramento River Bank Protection Project. This will increase Corps of Engineers' capability to reduce erosion damage to the levee system, which protects more than one million acres, two million people, and more than $26 billion in property.

- Restoration of 4,000 acres of historic San Joaquin River floodplain, wetlands, and riparian areas at the San Luis National Wildlife Refuge.This will temporarily store and thereby reduce peak flows and help protect properties downstream.

FEAT also urged the U.S. Geological Survey to expand and adequately fund a long-term stream gage database for rivers and streams, which will help improve floodplain mapping.

DWR's Assigned Tasks
Because the Department of Water Resources is the state's lead agency in flood operations, the Governor directed it to perform the following tasks:

• Improve computer modeling and floodplain mapping capabilities to support both the State Reclamation Board's Designated Floodway Program and the Federal Emergency Management Agency's National Flood Insurance Program mapping efforts.

• Inspect all dams that made large spillway releases during the flooding and, if necessary, require dam owners to make repairs to assure downstream safety.

• Encourage citizens to improve private levees to Corps of Engineers standards or pursue nonstructural alternatives.

• Ensure that computer-based flood event tracking and reporting systems are completed, maintained and staffed, including training of emergency staff.

The Department will also work with the State Office of Emergency Services, which the Governor has assigned to develop and test new guidelines for coordinating local, state and federal emergency field operations during flood emergencies.

Long-Term Flood Management Challenges
In developing a new master plan for flood management in the Central Valley, the Reclamation Board, U.S. Army Corps of Engineers, and other planners will consider the full range of structural and nonstructural methods, including additional seasonal reservoir space, new reservoir storage, new or enlarged flood bypasses, channel clearing, sediment removal, and levee setbacks.

"There is no single solution to California's flooding problem," says DWR Director David N. Kennedy, a FEAT member. "There is more emphasis now on not controlling everything in levee channels, because that creates more problems elsewhere. Still, there are levee projects that need to be finished."

The team members recognize that comprehensive, basinwide planning for flood management is essential and will be an arduous task with many rewards. In their report, they wrote:

"We have a chance to learn from the lessons of these floods and to shape for Californians in decades to come a new approach to flood management that corresponds to the realities of California today and in the 21st century. If the lessons learned from the January floods can be put to use in reducing the threat of another such catastrophe, then some good will have come of the losses endured by so many earlier this year."

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FEAT Recommendations

Among key recommendations included in the Feb. 10 Preliminary Report of the Governor's Flood Emergency Action Team are:

- direct DWR to install new stream gauging stations and telemetry in areas found deficient during the floods;

- direct DWR to establish a new Levee Rehabilitation Unit to work with the U.S. Army Corps of Engineers to restore levees to pre-flood conditions, prior to the 1998 flood season;

- direct DWR and the Governor's Office of Emergency Services, working with affected counties and landowners, to support development of local plans for emergency repair of "private" levees and submit those plans to Federal Emergency Management Agency for federal funding;

- direct OES to conduct workshops with state, local and federal agencies, and the media, in areas at risk during this flood season, to review roles and procedures related to dissemination of flood information and public warnings; and

- direct CALFED, as part of their planning, to optimize use of Proposition 204 and Central Valley Project Improvement Act funds for projects which incorporate both flood control and habitat restoration.

Other recommendations covered the reimbursement of federal disaster claims, state assistance for national parks damaged by the January floods, a campaign to promote tourism in flood-damaged regions, and a number of requests for federal action on levee repairs and rehabilitation.

Governor Wilson had already directed OES to advance $8 million in state funds to counties most affected by the flooding and DWR to pump out ponded water in 70,000 acres of land, which was posing a threat to existing levees and causing a health and safety hazard.

A second report, the 120-day report, will take a comprehensive look at the state's long-term flood protection needs and review the overlapping responsibilities of private, local, state and federal authorities in maintaining and improving the state's levee system and its offsite storage system.