First Alert Forward: Preparing STL for climate resilience

ST. LOUIS, Mo. (First Alert 4) — Rising temperatures and heavier rainfall in St. Louis are prompting engineers, designers and city officials to rethink how roads, parking lots and sewers are built.

Average annual temperatures in St. Louis have increased 4.4 degrees since 1970, and annual precipitation has increased 8.7 inches over the same period, according to data from Climate Central.

As a result, private business and public agencies are trying to account for those increases, designing infrastructure that will serve the region a century from now.

Outdoor spaces designed for sustainability

Ted Spaid is the founder of SWT Design, a firm specializing in outdoor spaces and landscaping. The company has projects throughout St. Louis, including several in Forest Park such as Art Hill and Jefferson Lake.

“We use our space as an outdoor laboratory,” Spaid said.

SWT’s Shrewsbury office includes a rain garden, a permeable parking lot, rooftop gardens and solar panels.

“This absorbs water and moves it underground,” Spaid said.

“The one thing we can build smarter is to think about how things can be used. How can a garden serve more than an aesthetic function?” Spaid said.

Spaid has worked in the field for more than 40 years and said he has seen the environment change.

“Everything from the temperature swings, to the annual rainfalls seeming more intense, even plantings. Things we would normally plant in Arkansas can live in St. Louis now,” Spaid said.

Underground stormwater systems

Not every solution involves a garden. Mark Joersz works with ADS Systems, a stormwater engineering firm. The company designed an underground holding tank system in Fenton 20 years ago, near the Meramec River in an area prone to flooding.

“It’s basically an underground holding tank,” Joersz said.

“Most people don’t know they’re there. There’s probably a thousand of these around the St. Louis area,” Joersz said.

ADS Systems is currently installing a similar system in Bridgeton that holds water during a heavy storm and drains it slowly, reducing runoff and minimizing flood risk.

“This system will be here for 100 years probably,” Joersz said.

The Fenton system has protected nearby businesses through several flooding events, including one around the holidays in 2015.

“People might remember it flooded out two water treatment plants because of that rain. This system wasn’t even full after that,” Joersz said.

Average rainfall intensity in St. Louis has increased 23% since 1970, according to data cited in the report.

“We’re seeing more intense rains than we used to see. It’s become more acceptable for engineers, for the federal government or MSD, to mitigate flooding and erosion and rapid river elevations. All of this is more forefront, where stormwater used to be a forgotten asset in the government,” Joersz said.

Aging infrastructure and sewer upgrades

Bess McCoy works with the Metropolitan Sewer District (MSD), which has started work on hundreds of projects funded through Prop S, a 2024 ballot measure generating roughly $35 million a year for MSD.

“Some areas of the city that should have stormwater infrastructure don’t,” McCoy said.

“We’re looking at what size storm should we be designing for? What are ways we can address stormwater beyond infrastructure,” McCoy said.

A new inlet in South City will help protect homes in the neighborhood, but McCoy said sewer upgrades alone won’t be enough in some cases.

“Even when that’s complete, our system won’t be immune to the effects of climate change. We need to look beyond the pipe. We need to incorporate plumbing codes, building design and neighborhood design for a climate-resilient St. Louis region,” McCoy said.

Rising temperatures add strain

Over the last 50 years, St. Louis has warmed more than four degrees, compared with two and a half degrees for Missouri overall and nearly three degrees nationwide, partly due to the urban heat island effect. That has put additional strain on roads, water mains and sewer lines.

Heather Navarro is a former St. Louis alderwoman who now works with the Midwest Climate Collaborative, which develops regional strategies for dealing with climate change.

“It impacts how we get to work, how people get to school,” Navarro said.

“Everything, our buildings, our tree canopy, even the clothes, we wear are designed for a certain average temperature and right now that average is shifting,” Navarro said.

Asked what actions should be taken, Navarro said data collection is a priority.

“We need to be collecting data right now. We need to learn from other regions that have a similar climate to what we have. What do they plant? What materials do they use? We’re going to see movement over the next few decades due to climate change. We want to be able to bill ourselves as a climate-ready city. We need people to know they’ll be safe here, that they won’t go broke heating or cooling a building, that they’ll be safe from flooding. Developers want that, too,” Navarro said.

Cost of investment

Much of the infrastructure involved is costly, but those working on the projects said they consider it a long-term investment.

“The goal is to do things better, to create an infinite future as best as we can,” Joersz said.

“By having systems that are upsized, it can save money in the long run so you don’t have to upgrade anything else,” Joersz said.

“Have that mindset about ‘what will this be like in 100 years?’ Just be passionate about it. That will make a huge impact in how we see climate resiliency, but also how we as individuals can have an impact, whether it’s in your backyard or at work, going outside and enjoying it, or talking to people who are spending the money in your cities,” Spaid said.