Lessons from Texas: California cannot afford to delay flood protection | Opinion

When historic floods tore through Texas this summer, claiming more than 130 lives, it was a grim reminder of what happens when flood protection falls short. But California’s flood protection system — already underfunded— is just one severe storm away from facing our own version of that tragedy.

The U.S. Geological Survey uses the term “ARkStorm” (short for “Atmospheric River 1,000-year storm”) to describe a worst-case flood scenario for California. It envisions a sequence of powerful Pacific storms pulling enormous streams of tropical moisture across the ocean and dumping it on the state for weeks.

In this model, the sheer volume of rain and snowmelt overwhelms rivers, levees and reservoirs, causing flooding on a scale far beyond anything in living memory and reminiscent of the winter of 1861-62, when weeks of relentless rain transformed the Central Valley into an inland sea that stretched hundreds of miles.

In 2022, the U.S. Geological Survey released the updated “ARkStorm 2.0” scenario, modeling what would happen if a chain of these massive storms hammered California for weeks. The result is chilling: catastrophic flooding across 4,000 square miles, the displacement of millions, the long-term closure of highways and over $1 trillion in economic losses. Los Angeles, the Bay Area and the Central Valley would all be in the crosshairs.

We know what is needed: California’s Central Valley Flood Protection Plan, the state’s blueprint for managing flood risk in the Central Valley, calls for significant investments (up to $30 billion) over the next 30 years. Although no amount of investment can erase the risks of an ARkStorm entirely, fully funding and implementing the plan would shore up our levees throughout the Central Valley and greatly reduce the danger to life, property and critical infrastructure.

Hundreds of millions of dollars are needed annually just for routine operations and maintenance. Yet annual flood control spending falls woefully short — roughly 30% below what experts say is required — and funding comes in unpredictable bursts, usually only after major flood damage occurs, rather than steady commitments to help prevent costly damages.

Without a stable, multiyear funding framework, urgent repairs are delayed, costs escalate and communities remain exposed.

This is not theoretical, as we have already seen the warning signs: Pajaro and Planada in 2023, urban flash floods in Los Angeles in 2024 and levees under strain in the Sacramento-San Joaquin Delta. Climate change is supercharging the risk. Storms that used to have a one-in-200 chance of happening in any given year now have a one-in-50 chance of occurring.

And this is not just a Central Valley problem. In an ARkStorm-scale flood, Silicon Valley’s tech corridor could be submerged, water supplies for Southern California could be cut off for months and transportation arteries that move goods across the state could be impassable. The ripple effects would hit every Californian, and the state’s own budget would be gutted by recovery costs.

We have seen what happens when flood protection is underfunded or delayed. In Texas, this summer’s floods overwhelmed communities and left residents scrambling to escape rising waters. Warning systems and flood protection infrastructure were no match for the sheer scale of the disaster. California has the opportunity to act now, while there is still time, to ensure our own systems are strong enough to withstand the next major storm.

We have the plans, the expertise and the partnerships to dramatically reduce our flood risk. What we lack is the sustained investment to match the scale of the threat. The governor and Legislature should commit now to consistent, adequate funding for flood control, treating it as the core public safety and economic stability priority it is.

Adam Borchard is executive director of the California Central Valley Flood Control Association, which represents more than 60 local public agencies that maintain levees and provide flood control services to protect life, property and the environment.

This story was originally published August 29, 2025 at 6:00 AM with the headline "Lessons from Texas: California cannot afford to delay flood protection | Opinion."