How flood-prone areas of the USS North Carolina are adapting to rising sea levels



Drone photo taken of the USS North Carolina Battleship Memorial and flooded parking lot at high tide in Wilmington, North Carolina on November 28 (Justin Cook)

Another storm surge caused retired Navy Captain Terry Bragg to put on his ever-present rain boots and walk from his office into the flooded parking lot.

All around him on this ordinary Tuesday, water crawls over concrete seawalls and fills drains. It covers a strip of grass and engulfs most of the nearby fire hydrant. It eats up the sidewalk and inches past a dying oak tree hanging in Spanish moss. Leafless branches are an unmistakable sign that the roots are constantly exposed to salt water.

In just 30 minutes, it can be a foot deep, or more in some places. The water used up hundreds of parking spaces and created an obstacle course for people trying to get from downtown Wilmington across the Cape Fear River to the visitor center for the historic USS North Carolina, which has been moored here for more than 60 years. I created it.

“This is climate change,” says Bragg, the site’s executive director since 2009, as he stands ankle-deep in ever-rising floodwaters.

The giant battleship behind him is a floating museum and one of North Carolina’s most iconic and visited tourist attractions, and it has many meanings. The most decorated U.S. battleship of World War II, marked with 15 stars. and his enduring memorial to the more than 11,000 North Carolinians who served and died in that war.

But the low-lying Eagles Island site also faces serious risks from rising sea levels and constant flooding.

Museum leaders have documented a more than 7,000 percent increase in tide damage at the site since it opened to the public in 1961. The changes over the past decade or so alone are dramatic. In 2011, approximately 20 floods were recorded on the Battleship grounds. By 2020, the site was flooded about half of the year. That trend shows no signs of slowing down.

In 2022, the battleship had nearly 250,000 visitors, and despite the most successful fiscal year ever, the site suffered nearly 200 days of flooding. Officials have sometimes had to close it when the only access road becomes submerged or visitors can no longer safely navigate the salt lake that has formed in front of the 35,000-ton warship’s main entrance.

“If we can’t sell tickets and provide parking, we can’t keep Battleship open,” said Bragg, whose operations are overseen by a state commission but regularly receive state subsidies for its operations. Not received told about this place.

Without some intervention, there is little doubt that the problem will only become more dire. The battleship is located 45 miles upstream from the confluence of the Cape Fear River with the Atlantic Ocean and about a half-mile from the National Oceanic and Atmospheric Administration’s tide gauge, which has collected water level data continuously since 1935. in position.

According to the data at that time, Sea levels there have risen about 9 inches, but the rate of rise has accelerated over the past decade. Scientists predict that there could be another jump by mid-century.

“We’re seeing changes,” says Jenny Davis, a research ecologist at the North Carolina-based National Coastal and Marine Science Center, part of NOAA. “The number of floods will only increase over time.”

This is true across the East Coast, which faces increasing threats from rising sea levels and frequent flooding. But that’s where the story of USS North Carolina diverges from those of other places facing similar dangers.

Feeling the need to act quickly, and knowing that even more serious problems could ensue, site leaders decided several years ago not to try to stem the rising waters.

Instead, they will look for ways to live with the changes in the landscape around them, even if it means doing what many places don’t want to do: return the land to nature.

Over time, Bragg said he and his colleagues sought data and advice from coastal flooding experts, including NOAA. Several years ago, they solicited proposals from four architectural design firms for solutions to alleviate the constant flooding on the Battleship grounds.

“Three of the four said, ‘Let’s build a wall around it,’” he recalled.

Engineering firm Moffat & Nicol suggested a different path. In short, this has been accepted for many years in countries such as the Netherlands, but it has only been in recent years that it has taken root and become more popular in the United States: adapting to sea level rise rather than viewing it as a recession. It can be summarized in this idea. An enemy to be conquered.

Rising sea levels could engulf millions of acres in the U.S. within decades

“This is the concept of being able to look at water as an asset,” said Dawn York, a senior coastal planner at Moffatt & Nichol, who has spent years shaping the future of the USS North Carolina. .

“It has been proven time and time again that when you design projects that leave natural systems intact, they actually withstand events like storms better and require less maintenance over time. It’s more sustainable.”

The approach embodied at Eagles Island has several core elements.

At one of the lowest points on the site, workers removed approximately 800 feet of concrete barriers and other rock armor and installed an earthen berm to reduce wave and tidal erosion and create a range of biological habitats. Create a “living coastline” consisting of green and native vegetation. Wild animals such as shrimp and blue crabs.

There are plans to restore many of the flood-prone parking lots to resemble the streams and wetlands they would have been in generations ago. That means tearing down acres of pavement and other impermeable surfaces and replacing them with more natural landscapes, with the goal of capturing, retaining, and ultimately returning tidal floodwaters to the Cape Fear River. There is.

Such designs also leave open the option of expanding and adapting natural areas if sea levels continue to rise.

Meanwhile, the remainder of the battleship’s parking lot will be elevated above the current high tide line, and plans call for a complex of “green” infrastructure features to help manage and filter stormwater runoff.

The project will include planting approximately 100 trees and shrubs in the redeveloped parking area, as well as more than 130,000 native wetland plants to support nesting and migratory birds. It is.

“We’re going to improve water quality, we’re going to improve drainage, we’re going to improve safety,” said Chris Vargo, a retired U.S. Coast Guard lieutenant commander and battleship deputy chief. His family once bought him a tidal clock for Christmas. You might have to navigate a flood on your way to the office every day.

Construction on the project is expected to begin as early as this month and take approximately eight months. The goal is to finish ahead of the peak of the upcoming hurricane season, which runs from June to November.

The estimated $4.1 million cost of initial construction will be funded in part by nearly $2 million from a collection of state and federal grants, more than $1 million from the recently approved state budget and funding from the North Carolina Department of Natural and Cultural Resources. It is planned to be covered by .

“We planned it within our budget,” Vargo said, adding that the environment around the ship changes so rapidly that “no one knows how much water we’ll actually be handling.” . [in the future]”

Those who helped shape the Living with Water project say they are grateful to leaders on the battleship’s field for their willingness to experiment with ways to alleviate chronic flooding.

“They’re not fighting to hold back water,” said NOAA ecologist Davis. “This is not an approach that is done most of the time, so it’s novel in that respect.”

York said that while the project is not large-scale, it shows what is possible if other places facing similar problems are willing to adapt by rewilding certain areas. He said he would be able to show it.

“They’re willing to give up land that they can never get back to return to its natural use. They knew it was necessary,” she said. “The real risk is doing nothing.”

“There are no guarantees.”

Bragg has high hopes that the nature-based overhaul will lead to brighter and drier days for the USS North Carolina in the coming years. But given that sea levels continue to rise and scientists expect more strong storms and torrential rain to hit the East Coast in the future, this study is unlikely to provide a permanent solution. He is aware that it is low.

“I think this project has a 15- or 20-year design period for resolution,” Bragg said. “If flooding and climate change continue to manifest as they are, we will continue to have problems.”

For York, that timeline seems exactly right. Current projects are not intended to prevent damage caused by major hurricanes or flooding caused by major floods. But it should buy time from the near-daily flooding that has plagued the historic site in recent years.

“There are no guarantees,” she said. “As climate impacts continue to increase, other adaptations may be needed to make this site sustainable in the future. It will be a very interesting case study of how species can be maintained in their environment over time.”

But York, who has lived in Wilmington for nearly 30 years, also called the effort “probably one of the most personally and career-gratifying projects I’ve ever had the opportunity to work on.” .

If successful, the project would not only help preserve and enhance a part of the coastline she cherishes, but also honor military personnel such as her late father, a Navy veteran, and her grandfather, who served in World Wars. It will also help protect the places we honor, she says. Second World War.

“For me, it’s a commitment to history and the environment,” she said.

Source link

Leave a Reply

Your email address will not be published. Required fields are marked *