The cities, villages and farms along America’s most famous river are in flood mode again.
The Mississippi River has flooded at least 26 times since the first recorded event in 1543. Because of their size and destruction, nine events have earned the title “Great,” including the Great Mississippi Floods of 1927, 1993 and 2011. The loss of life and property from the historic flood underway now will depend again on the strength of more than 2,200 miles of levees, floodwalls and other flood-control structures built along the river’s banks and tributaries.
Prospects for the river’s 4 million residents, 1.5 million homes and 33,000 farms may not be good. Like many of the 40,000 miles of levees and 91,000 dams in the United States, those in the Mississippi River Valley have seen better days. In its most recent audit, the American Society of Civil Engineers (ASCE) gave them a nationwide grade of D.
Once the water recedes — it took months during the Great Flood of 2019 — residents and governments should decide whether to reinforce or replace structures that failed or performed poorly or to try another form of protection. The latter option may be best, because America’s approach to these disasters must shift from flood control to flood avoidance.
Given the uncertainties of what climate change will do in the future, we should give up the hubris that we can control nature with bulldozers, dirt and concrete. Instead, we should help people move out of floodplains and employ “nature-based measures” to reduce the force of future disasters.
Floods are already the most common and costly weather disasters in the United States. They will get much worse as climate change accelerates snow melt and produces more intense rainstorms. Unfortunately, these adverse impacts are increasing while dams and levees are aging and suffering from deferred maintenance.
The average flood-control dam in the United States was built nearly 60 years ago, while the average levee is past 50. Engineers built most of these structures to remain reliable for only 50 years. Virtually none were designed to handle the size and intensity of today’s floods.
Unfortunately, there is no coherent national plan to deal with floods or any of the adverse effects of climate change. Congress must make hard choices between spending hundreds of billions of dollars to repair and upgrade flood-control structures or tearing them down, returning the land to rivers, and putting nature’s flood controls back to work. Either way, riverside and oceanside communities should prohibit further real estate development in floodplains rather than encouraging it to gain more property tax revenues. A study in Nature Sustainability concluded that every $1 spent on buying flood-prone land saves at least $5 in future damages.
Nature-based options include wetland restoration, watershed reforestation and more porous urban surfaces to prevent runoff. Another option is to set levees back farther from river channels so flood waters can spread out and slow down, making them less powerful and allowing the ground to absorb more water. Last November, the White House issued a guidebook on nature-based solutions, with case studies, guidance, tools and lists of resources.
However, the most permanent, reliable and cost-effective way to avoid floods is to relocate as many homes and as much infrastructure as possible from natural floodplains. Unfortunately, more Americans are moving into riverside and coastal floodplains today than out. That will have to change because traditional flood response and recovery will get too expensive as climate change takes its toll. Property owners will see their insurance premiums increase — and property values decrease — due to coastal and riverine disasters. And even with federal recovery money, the personal expenses families face for flood recovery are often overwhelming.
“For years, even as seas rose and flooding worsened nationwide, policymakers stuck to the belief that relocating entire communities away from vulnerable areas was simply too extreme to consider — an attack on Americans’ love of home and private property as well as a costly use of taxpayer dollars,” The New York Times reported in 2020. “Now, however, that is rapidly changing amid acceptance that rebuilding over and over after successive floods makes little sense.”
“Scaling up buyout efforts could save taxpayers billions—or more—in disaster response and recovery over the long term, and spare countless households catastrophic losses,” according to the “flood-prepared communities” program at Pew Charitable Trusts.
The Federal Emergency Management Agency and the Department of Housing and Urban Development offer financial help to communities that purchase floodplain property and return it to its natural state. FEMA will pay 75 percent of the cost. But this “buyout” program is too little used and must be improved to make it more appealing for homeowners. At last report, the government took up to 5 years to complete the buyout process. Pew has published a comprehensive list of recommendations for reforming the programs.
In short, a proverbial perfect storm confronts Congress and localities: more frequent and severe flood disasters with inadequate dams and levees threatening the more than 40 million Americans living in riverside flood zones and many millions more living where sea levels have risen faster than at any time in the last 120 years. The problem won’t fix itself; the ASCE reports the number of dams whose failure would cost lives has doubled over the previous 20 years.
What makes the most economic sense? Rehabilitating federal and private dams would cost more than $90 billion, the ASCE estimated two years ago. Improving and maintaining the highest-risk levees would cost $21 billion. The cost of relocating 1 million flood-prone homes would be $180 billion, but it would save nearly $1.2 trillion over the long term, according to a study published in 2000 by Scientific American. The study found that relocation would be much more cost-effective than conventional measures like elevating homes, floodproofing basements and moving critical equipment from basements.
It makes sense to head off the storm rather than wait for it to overwhelm us. That’s always been the case, but never more than now.
William Becker is the author of “The Creeks Will Rise: People Coexisting with Floods,” published by Chicago Review Press.