EUREKA — Kathy Butler now keeps waders, rubber boots and water pumps in her law office.
The old brick building on South Central Avenue wasn’t in the flood plain in the 1980s. But it is now. In 2015, the Meramec River filled her crawl space and lapped at her front door. Two years later, sandbags just barely kept the water at bay.
And that makes Butler another advocate for change in this west St. Louis County river town.
“I don’t know how you continue,” said Butler, who also serves as the city attorney. “Either you have to shut down this whole area, or you have to stop the water coming in, somehow.”
Eureka is now rethinking flood management in a way it never has. The city and U.S. Army Corps of Engineers are evaluating a dozen strategic options, from the use of levees and walls, to buyouts of high-risk properties, to the restoration of flood plain as water storage.
The unfolding conversation facing the community — St. Louis County’s fastest-growing city — reflects one of the defining questions of the time: How to live amid increasingly wild and unpredictable surroundings. And the breadth of solutions under consideration in Eureka hint at the changing ways that towns are thinking about their relationships with local rivers. Long-prevailing practices like levee-building and flood plain development are attracting mounting skepticism about their compatibility with a more erratic climate.
“Things are slowly changing,” said Jon Remo, a Southern Illinois University Carbondale professor specializing in flood and river management. “We’re seeing more broad thinking about how to address these flood mitigation issues under a changing climate.”
“These towns on the Meramec are going to have to decide what they’re going to do if they keep getting repeatedly flooded,” Remo said. “We all have to think about our relationship with rivers, and not only what makes sense today, but also what makes sense in the future.”
The earth’s warmer atmosphere has the potential to hold more moisture, increasing the likelihood of heavier downpours. And as St. Louis-area cities grow and add homes, streets and shopping centers, all of that concrete increases runoff into the region’s rivers. To make matters worse, sections of river no longer have room to spread out into natural flood plain, as they once did. Levees hold swollen waterways in channels, which can exacerbate flooding both upstream and downstream, experts say.
Those problems have added momentum to flood-prevention alternatives, such as buyouts of high-risk properties that flood repeatedly and are increasingly in harm’s way. And a newfound emphasis on “green infrastructure” aims to restore flood plains and harness nature’s ability to absorb water.
Experts said that, in the last five to 10 years, the mounting toll of floods has helped spark a pronounced movement away from conventional river management. Instead, natural solutions for water absorption have become a top priority, particularly in areas of repetitive loss, said Colin Wellenkamp, executive director of the Mississippi River Cities and Towns Initiative, which works with mayors of communities throughout the river corridor.
“Those can regulate and tame a whole lot more water than any built infrastructure ever could,” said Wellenkamp. “It’s the only thing we really can afford, and it’s the only method that really reduces risk at a systemic level, at corridor scale. That’s really the direction where our mayors are headed.”
He provided some regional examples. In the Metro East, for instance, he said current work is exploring the potential for Horseshoe Lake to serve as a basin for water storage. Similarly, flood plains have reopened for water diversion by Grafton, near the confluence of the Illinois and Mississippi rivers. And by the mouth of the Meramec, the river communities of Arnold and Kimmswick recently agreed that Arnold would not build a flood wall.
Eureka faces some tricky dilemmas, as it eyes the flood control playbook. Creeks that cut through the town on their way to the Meramec serve as direct channels for floodwater, endangering areas like the downtown district. While experts and residents alike think that some creekside levees could be needed, the community might ultimately face some unenviable choices and trade-offs.
“Maybe some of their old downtown’s got to go,” said Bob Criss, a Washington University professor who studies flooding. “A big flood wall right through the city, that’s going to be ugly, too.”
People in town recognize that something has to be done. They’re just not sure what that might be.
‘It’s just when’
Floods in 2015 and 2017 confronted Eureka with the Meramec’s highest crests on record, which inundated homes and businesses. The city estimates that damages exceeded $10 million — and would have reached far higher if not for “substantial” sandbagging efforts in 2017.
Many city residents and business owners have said they would not be able to financially recover from another major flood, said Mayor Sean Flower.
But another, residents say, is inevitable.
“It’s not a question of if it’s going to flood again, it’s just when,” said Butler, the city attorney. “We need to do something.”
The corps’ Eureka study examines the costs and benefits of various flood control options. Costs of the study, itself, are being split evenly between the city and the corps. If a project of up to $15 million from the list is ultimately approved — a determination that is not expected until next year — the city will shoulder about one-third of the construction costs, with the rest covered by the corps. Flood management projects over $15 million require separate authorization.
The study is examining where to place flood control structures — whether levees, flood walls or berms — to protect the town’s high school and sewage treatment lagoon, as well as Missouri Highway 109, which carves through Eureka’s heart. The corps has already screened out ideas deemed inefficient or expensive. Meanwhile, 51 structures have been identified in the 100-year flood plain, which could require mitigation — such as relocation, elevation or flood-proofing. Use of temporary floodwalls and “nature-based” solutions also remain on the table.
The city passed a local sales tax in 2018 to fund construction of two flood walls by Eureka High and the sewer plant — both of which sit near tributaries to the Meramec that have become sprawling backwaters during recent floods. The proposal, being reviewed by the corps, attracted a couple hundred comments from the public.
One thing many aren’t considering: A big new levee.
Not far downstream from Eureka, the Valley Park levee has fueled fierce controversy. In Eureka, residents say they don’t want to pursue projects that divert flood risk to neighboring areas. During a recent presentation by the corps and city officials, multiple area residents asked how flood walls might affect flooding elsewhere. Officials insisted the Eureka High walls, at least, would not create new flood risks.
“A lot of people in their head have a vision of, like, the Valley Park levee or the Chesterfield levee — something that would be right on a river,” said Flower, the mayor, during a virtual meeting in January. “These are a mile, mile-and-a-half back and they’re more around structures, like our sewer plant. So, they’re a little different.”
Something has to be done, said attorney Mark Antonacci.
His South Central Avenue building suffered $125,000 worth of damage from the 2015 flood, he said.
“I still keep stuff a couple feet off the ground,” said Antonacci, gesturing toward boxes and items perched along the edge of his office. He said that flood risk wasn’t even a part of the conversation when he bought the property 13 years ago.
“Things have changed,” he said. “The problem is the changing of the climate.”
Corps officials said that, later this year, a “tentatively selected plan” for local flood control efforts will be identified, subject to public review. After that, a recommended plan will officially be endorsed. Approval of a final report is not targeted until 2022.