WASHINGTON – The famed cherry blossoms around D.C.'s Tidal Basin are in peak bloom this week, but for 158 of the trees, it will be their last bloom. The trees will be cut down later this spring as part of a project to rebuild and raise the seawalls around the basin.

Daily flooding threatens trees, inconveniences visitors

Millions of people flock to Washington, D.C., each spring to take selfies among the cherry blossoms — some even get engaged. That's what Jody Axinn did some 20 years ago. Now, Axinn says, the romantic spot she remembers is unrecognizable.

"The part that we got engaged in is now under water. The whole path, the whole section, it's under water," Axinn says. "I come down and tell my kids, 'Children, Dad and I got engaged in that watery area.'"

Every day, twice a day, at high tide, portions of the walkway around the Tidal Basin flood with several inches of water. Some of the roughly 2,500 cherry trees around the basin have water lapping at exposed roots; others are completely inundated. Numerous park benches are partially submerged.

"When I got here 10 years or so ago, it was a regular occurrence, but certainly not twice a day, every day," says Mike Litterst, a spokesperson for the National Park Service. "The only variable now is how far inland is the water going to go on any given day."

The cherry trees around the Tidal Basin were first planted more than a century ago — a gift from the mayor of Tokyo, and a symbol of international friendship.

Sinking land, rising water

There are two forces working together to undermine the Tidal Basin, and the trees and monuments around it. The land around the basin, built using mud dredged up from the Potomac River bottom, is sinking. That has allowed the land to settle by about five feet over the past century. At the same time, the water level has gone up by more than a foot because of climate change.

"Combining those two factors, you now have water six feet above where the seawall was originally designed to keep it out," Litterst says.

The Tidal Basin looks like a small lake, but it's actually part of the Potomac River. There are gates at the upstream and downstream ends of the basin that allow river water to rush through, ebbing and flowing with the tides. Because the river is tidal, it is gradually rising along with the level of the world's oceans, as ice sheets and glaciers melt because of the burning of fossil fuels.

This year, the cherry trees reached peak bloom at the second-earliest date on record, according to the National Park Service. In recent years, the average peak bloom date has moved about a week earlier, due to the warming climate.

Later this spring, the park service will break ground on a major project to raise portions of the walkway around the basin and along the Potomac River. Officials say the new seawall will be high enough to withstand about 100 years of future sea level rise. It's engineered so it can be built on top of, if needed.

It would be impossible to complete the $113 million project without removing the trees along the water, Litterst says.

"The problem is if we don't fix the seawall, we're losing trees every year because of the water. They can't be replanted until we fix the source of the problem," Litterst says.

The project is slated to be finished in 2027. In the meantime, the northern and eastern sides of the Tidal Basin will still be open to the public. When the project is complete, 274 new cherry trees will be planted.

So long, Stumpy

Among the trees to be removed is one very famous tree known as "Stumpy."

It's a scraggly tree with a trunk that is mostly rotted out. At high tide, the base of the tree is flooded. Yet, each spring, Stumpy's three or four small branches burst into flower, with the Washington Monument standing tall in the background.

"I just fell in love with Stumpy," says Debby Swope, an eighth-grade history teacher visiting from Oregon. "Stumpy is my emotional support tree in Washington, D.C. He just represents perseverance and courage, and cuteness."

Still, looking at Stumpy during high tide, Swope sees the need for the project. "His feet are wet," she says.

Stumpy, and other low-lying trees, will be torn out to make way for construction equipment. But clippings from the famous tree will be sent to the National Arboretum to propagate new trees.

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