Because of Harvey, the Houston region has a lot of expensive work to do. Photos of submerged freeways hint at the scale and scope of the damage to infrastructure: roads, sewers, water supplies, drainage systems, the METRORail light rail system, telephone and cable services, parks, and public buildings have all suffered damage. The storm’s winds and unprecedented rainfall also damaged or destroyed over 185,000 homes. Preliminary estimates of Harvey’s toll range from $70 billion to $190 billion. This would exceed the $50.7 billion that Congress provided for recovery from Hurricane Sandy in 2013, and possibly even the $120 billion provided after Hurricane Katrina in 2005.

But even an open funding spigot would not enable the people in Harvey’s path to avoid a long and difficult slog back from disaster. Most federal post-disaster aid goes to public infrastructure, and only about 10% to private homeowners. Moreover, it often takes years for homeowners to see their fraction. Tenants are often completely out of luck. All in all, many people spend years living in motels, trailers, and parents’ or friends’ basements.

Before deciding how to approach recovery, officials and residents should absorb two basic features of the situation.

First, Harvey is Houston’s third “500-year storm” in as many years. (We put that phrase in quotes because it has lost its meaning.) The climate is changing in ways that will make coastal storms still more frequent and severe. There is no telling when the next “500-year storm” will hit Houston—will 2018 break the streak and be the city’s first year in four without one? Even now, Irma is bearing down on Florida, which Matthew hit hard last year, and the 2017 hurricane season has only just begun.

And second, Houston’s boomtown-style development made it susceptible to floods. It’s famously the only major U.S. city without zoning. Houston’s rapid growth and expansive sprawl owe in part to its lax development restrictions. These have led to houses in flood plains, and pavement replacing wetlands and pervious soils. The city’s growth has also outpaced the expansion of its stormwater infrastructure.

With these features in mind, and recognizing the whopping costs of developing a flood-prone region in ways that are vulnerable to flooding, decisions must be made about how and where to rebuild. When the state and local governments affected by Sandy faced similar decisions, they drew on New Orleans’s experience of Katrina and devised recovery programs aimed at building back better. These programs shifted people and structures out of flood plains (at least partially), redesigned buildings and infrastructure to reduce their vulnerability to flooding, and required planners to take climate change into account when authorizing proposals for long-lived projects like electrical infrastructure.

Many of these programs relied on federal money. The 2013 Sandy recovery legislation did not call for rebuilding differently. This left agencies unsure in some instances about whether federal dollars carried restrictions against anything other than restoring the status quo ante—even though that would mean reproducing the same vulnerabilities revealed by the storm.

The areas affected by Irma and Harvey need to prepare themselves for the next catastrophe. Congress can help by directing money appropriated for recovery to be spent on making the regions more resilient to the storms that are sure to keep coming.

Michael B. Gerrard is a professor and faculty director of the Sabin Center for Climate Change Law at Columbia Law School. Justin Gundlach is an associate research scholar and climate law fellow at the Sabin Center.