BATON ROUGE, LA – What do New Orleans, Louisiana, and Charleston, South Carolina, have in common? The foundation of both southern cities’ modern infrastructure was built on marsh land in the 19th and 20th centuries.
Through a combination of turn-of-the-century drainage systems, the shoring-up of levees, the filling of creeks and marshes, and other changes to the topography of the land through urban development, each city was designed to exist on stretches of land that were engineered into existence.
Around 1900, municipal drainage systems allowed New Orleans to spread onto former marshes, according to a study from the Center for Bioenvironmental Research at Tulane and Xavier universities.
Much of Charleston is built on similar foundations: creeks and marshes that were filled to make way for more infrastructure, said Evan Thompson, executive director of the Preservation Society of Charleston.
Now, pieces of the foundational infrastructure creating and preserving the cities are over a century old. And water that was displaced to create the land is starting to creep its way back in.
The New Orleans drainage system “starved the land of replenishing sediment,” said Richard Campanella, associate director of the Center for Bioenvironmental Research. “As a result, former marshes sunk as much as 8-12 feet, while unleveed wetlands eroded at a pace of 10-35 square miles per year between the 1930s and early 2000s.”
Andy Sternad, an architect for Waggonner and Ball, a resilience-focused architecture firm based in New Orleans, says that Charleston is currently experiencing sea level rise and flooding regularly from high tides when it never used to.
This high-tide flooding, also called nuisance or sunny day flooding, is when the sea spills onto land during extremely high tides, inundating low-lying areas with seawater until high tide has passed, according to the U.S. Climate Resilience Toolkit.
This type of flooding occurs more than twice as often as it did in the year 2000 due to rising seas, according to the National Oceanic and Atmospheric Administration. The NASA Earth Observatory records that Charleston experiences tidal flooding every four to five days on average.
“As sea levels are rising, that place is at risk sooner than many other places in the country, in league with places like Miami or New Orleans,” Sternad said. “The sea level rise is a problem that’s very real there and urgent. And on top of that, with threats from storm surges and hurricanes in the Atlantic, they’ve really got to do something.”
Waggonner & Ball is collaborating with the U.S. Army Corps of Engineers on its Peninsula Flood Risk Management Study to protect Charleston from increased risk of sea level rise, storm surges and flooding.
The firm is leveraging the expertise it developed in the wake of Hurricane Katrina in 2005. Its team is connected with experts from another region that has experience living with water: the Netherlands.
The Dutch have cultivated expertise in living on the coast for over 800 years. Because of their engineering, the Netherlands has gained land instead of losing it, even as sea level rise and coastal erosion threaten other coastal areas.
“The Dutch for hundreds of years have lived below sea level,” Sternad said. “The famous Dutch windmills from centuries ago were water pumps; they were lifting water out of farm fields to higher ground; they weren’t mills like they were in other parts of the world. So, the Dutch have lived with water for a long time.”
After the devastation of Hurricane Katrina, the Dutch offered foreign aid to New Orleans as flood protection experts. Waggonner & Ball teamed up with these experts to form a collaborative workshop series called the Dutch Dialogues, which is now active in Charleston to facilitate the firm’s work there.
The first series, which was out of New Orleans just after Katrina, led directly to the Greater New Orleans Urban Water Plan. The water plan is intended to rebalance New Orleans and its relationship to its environment.
“The way the city has been engineered is out of sync with the natural landscape and the natural delta environment,” Stenard said. “The fact that we’ve created this engineered city and sunk the land has a whole bunch of consequences—not only for something like Katrina, but day-to-day pumps breaking, streets flooding, the ground sinking and cracking, which breaks pipes that are buried. There’s a lot of consequences.”
Growing up in Lafayette, Louisiana, Madalyn Mouton has always felt Louisiana’s infrastructure was inadequate.
“When I go out of state, I always ask myself, ‘Something feels wrong. Why is the road not bumpy?’ And then I remember I’m not traveling down Louisiana’s unsafe roads,” Mouton said.
As a facet of the Biden administration’s American Jobs Plan, Louisiana received a D+ on its Infrastructure Report Card, which cited a decades-long “systemic lack of investment.” Mouton was quick to add, “I think a D+ is accurate.”
In addition to unsafe roads, Mouton points out the infrastructural concerns centered around flooding, evident even in her daily life. She cited her old school’s auditorium, which notoriously floods after a heavy rain.
“Given how close Louisiana is to water, I think we need to build our state’s infrastructure with more consideration of our unique problems that we have with water,” she said.
Initiatives such as the Greater New Orleans Urban Water Plan intend to invest in existing infrastructure and build anew to ensure resilience against the effects of climate change as threats such as flooding and sea level rise become more prominent.
For urban planners and visionaries such as Sternad, these issues provide a chance to innovate by not just improving the resiliency of cities’ infrastructure, but also the quality, functionality and value that it adds to communities.
“It can be completely overwhelming to think about these problems and what we’re facing,” Sternad said, “but I think this climate change hour ahead of us that’s opening now is really the problem of our generation and our time and future generations. . .but we can move forward in a way that maintains our culture and our values and a lot of the things about the places we live in. “So, I think I would just end on a note of optimism, that now is the time to get it right.”