Charleston faces an existential choice: Wall off the rising ocean or retreat to high ground – Charleston Post Courier

In the beginning, Charleston built a wall.

For the first century of its existence, the community first known as Charles Town fortified itself with barriers, moats and bridges, and cannons perched atop it all.

The protections for the small settlement at the confluence of the Cooper and Ashley rivers were meant to keep out the French and Spanish. Later, the denizens tried to repel the British monarchy that had launched the whole affair. The city could not exist without protection, and, for years, that was what its leaders most often spent money on.

But in its 350th year, the city is considering this old strategy for a different enemy: the rising sea that threatens to one day swallow it whole.

The proposal, laid out at the end of last month in a lengthy report by the Army Corps of Engineers, would create an 8-mile perimeter around the city's core peninsula, slicing through the marshlands that blossom out from the water's edge or following the paths of streets on higher ground. It would make the city's tallest seawall 3 feet higher, and the Army Corps says the project should fend off the water for 50 years.

The Corps has been clear, as have others who have studied flood threats on the peninsula. When the wall of water pushed by a hurricane comes, there are few other options to stop it than a wall of your own.

The porous coastline, with many rivers threading in and out of the estuary, welcomes the surging ocean at so many points that it would be too costly and complicated to create a gate system. And the peninsula itself, filled in over decades with dirt or sawdust or even trash, is already seeing increased tidal flooding as sea level rise slowly reclaims former creekbeds.

And so the city is left with a question: Does it defend its position once again, or start planning to leave?

On Friday, Feb. 22, 2019, historians tried to determine the path of an early city wall where these bricks were exposed during the construction of a new hotel at East Bay and Cumberland streets. They are believed to date to that early wall because of the bricks' bright red color and the stark whiteness of the mortar. File/Staff

"Im not going to be the mayor of Charleston that calls for the retreat," Mayor John Tecklenburg said. "Im not going to head for the hills."

The Corps' proposal includes pumps and a wavebreak at the peninsula's southern tip, as well. At $1.75 billion, it would by far be the most costly flood control project ever in South Carolina's Lowcountry. Many people expect the actual cost paid out years into the future if Congress approves it will be higher.

Some worry about whether the city will ever find its $600 million share, particularly as the spread of the novel coronavirus saps municipal budgets. Or they ask if this particular project, which only deals with one type of flooding, will distract from efforts to do work elsewhere.

And it's still not even clear what the wall would look like or where its exact path will lie. The path could change to some degree even up to the point of construction new technology might make it easier to build in places thought impossible before, or an archaeological discovery might re-route it.

The wall is designed to protect against hurricanes, and it's a gamble, every season whether one strikes. But it would likely have to fend off the more consistent threat of sea level rise, as well.

Dale Morris helped author the recent Dutch Dialogues report that used approaches from the Netherlands to study nature-based flooding solutions in Charleston. He said the peninsula will eventually need some sort of persistent barrier if living and working there is going to stay viable.

In the time since Charleston built its first wall, the city imported more enslaved people than anywhere else in North America; endured two wars; survived deadly bouts of yellow fever and Spanish flu; transformed into a tourist destination; birthed one of the country's earliest preservation movements; and eventually expanded far beyond the peninsula, west of the Ashley River and onto three nearby islands.

In many people's eyes, the peninsula's historic legacy makes it essential to protect. And beyond that history, the peninsula is the beating heart of a growing region.

It boasts a renowned dining scene, serves as the center of a tourism destination that brings 7 million visitors a year, and houses key medical institutions, including the only five-star Veterans Affairs medical center in the Southeast.

Rob Young, who runs Western Carolina University's Center for the Study of Developed Shorelines, has long been critical of other Corps projects, like beach-building that spits sand in front of oceanfront homes.

But as sea level rise worsens, he said, compelling cases can be made for protecting some areas. The peninsula's historic value may make it one of them.

"One of the things I've always wished we were able to do in the United States is look at the coast as a whole and decide where it makes sense to spend federal dollars," Young said.

Beach nourishment projects are some of the most common Army Corps of Engineers work on the Atlantic Coast. Here, a pipe spits a slurry of sand and water back onto eroding Folly Beach on Tuesday, July 31, 2018.File/Staff

Right now, the landscape of federal protection is a free-for-all, with some places regularly awarded millions and others little at all. Young said he's never been able to parse why funding lands in some areas and not others.

The Corps also has a $98 billion backlog in projects that have already been drawn up. Like Charleston, several localities are in the midst of studies, including Nashville, Tenn.; Miami; and the Florida Keys. Local leaders in Norfolk, Va., have already approved their plan, which similarly includes 8 miles of surge wall and a mile-long levee, but it hasn't been funded by the feds yet.

In the next decade, even more places will probably get in line. But to get that federal share, Charleston must put up its own cash, and $600 million is just an estimate; the project cost as a whole is likely to grow, Young said.

Protecting the peninsula also makes sense, not only because of its cultural value, but because it helps float the tax base of the city, said Dana Beach, retired founder of the Coastal Conservation League. The League is a conservation and environmental advocacy group, and has been a key voice in many large infrastructure decisions in the Lowcountry.

There's a destabilizing future looming: the more flooding degrades commerce and land values there, he said, the harder it will be to raise local funds for any flood work.

But Beach was ultimately optimistic about finding the money for the work before that tipping point. State and federal interests, he said, have rallied before behind big-ticket items like the Arthur Ravenel Jr. Bridge and harbor excavation.

Few people, so far, are rejecting the Corps' proposal out of hand.

Susan Lyons, a leader of flooding advocacy group Groundswell, said she's still undecided on whether the project is a good idea. There's varying opinions inside the group, which consists of many downtown homeowners who have grappled with flooding for years.

Lyons said she's heard many people by default accepting that the plan will move forward, despite some reservations. She said there's a social pressure in the city not to rock the boat.

Influential leaders like the mayor and Historic Charleston Foundation are so far supporting the plan.

"It's an option, walking away (from the peninsula), but it's not being a team player," Lyons said. "In Charleston, you have to be a team player. ... I think people who are operating inside our culture know that."

Lyons wonders how this project might distract from other work around the city to deal with flooding. She said it's not clear how it fits into Charleston's overall strategy, including the Dutch Dialogues.

The High Battery was hit by waves as Tropical Storm Irma hit Charleston's peninsula in 2017. File/Brad Nettles/Staff

The Dialogues were a wide-ranging inquiry into living with water, an exercise that has been conducted in only a few cities around the country. Charleston city officials took a trip to the Netherlands as part of the process. In addition to a barrier around the peninsula, the final report suggested elevating flood-prone roads and intersections, creating spaces to help retain flooding rainfall, and separating the drainage systems that evacuate water from the area's central spine of high ground and slowly sinking land on the perimeter.

Kris King is the executive director of the Preservation Society of Charleston, an advocacy group foundedin 1920 that's dedicated to protecting the historic cityscape. Another open question, he said, is how the wall would change the feel of the city.

City officials want to beautify the barrier and create a pedestrian path on it, similar to The Battery sea wall that runs along the peninsula's southern tip. But King emphasized that the breakwater proposed for south of the city has been modeled at 4 feet higher than the barrier, possibly obstructing views of the water beyond.

"We need to not just accept it because its being offered up," King said. "We need to really understand this thing and ask the hard questions."

Morris, who helped lead the Dialogues effort, said the wall does mesh with the ultimate suggestion that the peninsula will need a barrier. But there are opportunities beyond the Corps' first draft, he said, to improve the design so the city might be able to store more rainwater.

That is one of the chief concerns of virtually everyone chewing over the proposal: Will it trap flooding rains inside the city?

The Corps says its five proposed pump stations would help drain water from inside the perimeter before it collects. But the engineering group is only tasked with offsetting any problems it creates, Morris said, not improving the already soggy situation.

Placing the barrier farther into the marsh on the Ashley River side, he said, would allow more storage space for rain to run off.

As for whether the wall would distract from other projects, Matt Fountain, who manages Charleston's drainage projects, said the city's dedicated fund for that work will not help pay for a wall.

For the wall to work, the underground tunnels, pipes and flood-stopping valves Charleston is already planning have to come to fruition. The Corps report says its design depends on these efforts working in tandem, including the massive underground tunnel system called Calhoun West. But that project is more a twinkle in project planners' eyes than reality, with no funding or schedule laid out yet.

Fountain's department is in the process of prioritizing which of the many smaller flood projects across the city should be completed first. A standard to do so will be presented to city council at the end of the summer.

Separately, residents of the peninsula are waging their own wars against the water.

Those who live in the lowest spots have constructed sandbag walls around their homes; staked out the best place to move a car when the waters start rising; in one case, demolished a flood-prone house altogether; and in the most expensive proposition,elevated their homes on pilings and cement.

They are fighting a tide that city officials estimate will rise 2 to 3 feet in the next 50 years. That might seem like a long way away, but natural cycles rarely change on a smooth upward trajectory. Last year, the city saw a record-smashing 89 tidal floods, which could be a severe blip in the trend, or could mean the city is on a more accelerated path than previously thought.

Only time will tell.

Bernard Mansheim's brick-and-stucco home on Water Street is in the process of being raised, hoisted into the air as 90 steel piles are driven deep underground to form a new foundation. The 450-ton house, built in 1857, has been swamped with a foot of water by passing cyclones two times in the past five years.

Mansheim, an infectious disease specialist, said that hoisting the house up 8 feet seemed like the only option to stay in the neighborhood. At its finished height, the home will be higher than the wall, and the whole process will take the better part of two years to complete.

Finishing a surge barrier around the city, he suspected, could take decades; his initial reaction is that the project is too costly and too lengthy to ever get done, especially as the coronavirus pandemic scrambles the economy. He also held a dim view of whether the wall could hold off sea rise over the long term.

"I'm as committed as the next person to maintaining the beauty and charm of this city," he said. "I just am very pessimistic about the 50- and 100-year future of the entire East Coast, much less Charleston. "

Market Street is flooded during 8-foot tidal flooding in Charleston Harbor on Thursday, Aug. 29, 2019, in Charleston. File/Andrew J. Whitaker/Staff

Facing this challenge is also the quieter, less obvious contingent: those who are planning to sell and leave.

Lyons, who lives in the peninsula's often-flooded southwest corner, said she's commonly heard some residents say they'll sell their home before flooding gets too severe to do so. Some are already trying it.

She sees it as a tricky proposition.

"I don't know that any of those people have a crystal ball, and if you think it's getting bad, so does everybody else," she said.

Mansheim said home sellers in his neighborhood are regularly asked if they've flooded, and buyers flee when they hear the history.

"I think the reality is that most people (with flood-prone homes) are to some extent paralyzed," he said. "They don't know quite what to do, and I think they're hoping they don't suffer the damage they did last year or the year before."

But putting a wall around those homes could create a false sense of security. Andy Keeler, who studies climate change adaptation at Eastern Carolina University, said protection often encourages re-investment because it creates the perception that all the risk has disappeared. In effect, it's still there, but has the potential to burst in catastrophically rather than slowly creep up.

In modeling Keeler has done, "the more you protect, the longer you stay and the bigger the crash is" when the protection is overwhelmed.

Without protection, its unclear when many people would get the same idea to abandon ship. The Army Corps has offered only a limited view of the damages that could happen in 2075 without a wall. Half of the peninsula's historic structures, half of its police stations, and 42 percent of its medical facilities would flood in a storm event that raises the sea to the height of Charleston's highest existing sea wall.

Keelersaid one opportunity to re-think comes in a major disaster, when residents are faced with rebuilding again.

Indeed, in some other South Carolina communities, successive storms have encouraged some to seek an exit. But in other cases, the federal safety net that kicks into gear after a disaster can actually stimulate modern development, as Hurricane Hugo did in the Charleston region decades ago.

All of these decisions are made on an individual level, one by one, as flooding victims consider their financial situation, their neighbors' choices and their attachment to home. It's what academics would call "unmanaged retreat," or the messy interplay of members of communities making their moves separately.

There's also "managed retreat," or government policy that dictates people to move. Most plans for this type of retreat don't get implemented in the United States, but one example are the buyouts mostly funded by the Federal Emergency Management Agency. These pay to tear down oft-flooded homes and leave the land clear after.

Most of the places where Charleston has practiced this strategy are far afield of what the wall would protect: west of the Ashley River and on James Island, the suburban sprawl that exploded out from the city center under the tenure of former Mayor Joe Riley.

Charleston entered this century with its outer limits expanding like a balloon. Not even two decades in, news developments are flooding out older ones, and the edges of the city are beginning to collapse in on themselves.

Charleston started with a wall, but it grew with dirt.

Fill dirt, that is. Private landowners and the city government itself hauled in whatever was available to raise low-lying lots. The city needed buildable land, but there was concern in the 1700s and early 1800s that persistently wet spots would create "miasmas," or noxious, illness-inducing vapors, said architectural historian Christina Butler, who has authored a book on the city's drainage.

It was tough going. Attempts starting in 1785 to extend East Bay Street south to the eventual southern tip of the peninsula washed out more than once when hurricanes blew through.

But the 19th century's attitude of urban improvement and control of nature pushed the work forward, and White Point Garden was opened, along with the High Battery. By the early 1900s, Charleston sold the lots it filled along Murray Boulevard to finance the expansion there, creating what has become some of the most vulnerable and priceyreal estate in the city today.

Together, the work created a promenade at the southern tip of the city that's still a popular place to stroll today, lined with columned mansions and prim gardens locked behind wrought-iron gates. White Point Garden features a gazebo and lawn shaded by stately, twisted live oaks.

But the engineering behind that beauty is reaching its limits. The Low Battery, essentially a retaining wall along Murray Boulevard, is being lifted right now to account for higher tides.

Construction crews work on the Low Battery wall project that involves building up the century-old seawall along Murray Boulevard between Tradd and Ashley streets on Friday, May 8, 2020, in Charleston. File/Grace Beahm Alford/Staff

Norm Levine, director of the Lowcountry Hazards Institute at the College of Charleston, said the project, like much work to adapt to rising sea levels, buys time to lessen the future effects of climate change.But that work to curb carbon emissions that heat the Earth has to continue regardless.

"All of this is a stopgap if climate change isn't slowed," he said.

It's a stopgap, too, in defending from the worst-case scenario for hurricane damage.

The wall would not be tall enough to stop the peak surge from a storm like Hurricane Hugo in 1989. The cyclone was the worst in modern memory along South Carolina's coast, but hurricanes can have wildly different effects across the same coastline. The wall would defend against the tides that landed in Charleston, but not the worst part of the storm, which landed to the north.

Designs are usually planned around the last disaster, not the next one, said Hermann Fritz, a civil engineering professor at Georgia Tech.

Case in point, he said, is the complex network of levees around New Orleans. In 2005, Hurricane Katrina seemed to spare the city of a direct hit, but surge rushed over some of the smaller levees along the lake east of the city. The system was built after a direct hit from Hurricane Betsy in 1965, and was meant to stave off a 200-year storm 40 years later, it failed.

Ultimately, Charleston may have to weather its next storm without any wall, even if the community rallies around it.

Congress, several people said, might not be motivated to fund it until after disaster strikes the city.

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Charleston faces an existential choice: Wall off the rising ocean or retreat to high ground - Charleston Post Courier