They are the pride of Washington, D.C., in springtime, and their fleeting longevity makes them an immensely popular tourist attraction: the Japanese cherry blossoms that border the tidal basin on the National Mall. 

Gifted to the U.S. by Japan in 1912 as a sign of friendship between the two countries, the flowering trees draw over a million tourists each year, with the National Park Service estimating 1.5 million will flock to the nation’s capital this year to take the sight.

What You Need To Know

  • The famed cherry blossoms around the tidal basin on the National Mall were a gift from Japan in 1912 as a sign of friendship

  • Now, over a century later, they are facing real threat from climate change, including an earlier blooming season and rising sea levels threatening their roots

  • The National Park Service announced this week a multi-million dollar plan to repair the seawall around the tidal basin, which will begin in May 2024 and run through 2027

  • NPS predicts about 140 cherry trees will have to be removed during construction, but the plan is to plant 274 new cherry trees upon completion of the project

But the cherry blossoms face threats from climate change. 

“We are seeing the effects of climate change and sea level rise every day here on the National Mall,” said Mike Litterst, Spokesperson for the National Park Service. 

The trees are blooming earlier than they did in years past due to warmer temperatures, with the Environmental Protection Agency reporting the average date of peak bloom has shifted about a week earlier over the past century. In that time, Litterst says the average temperature in DC has also increased by two degrees. 

The earlier bloom has a domino effect that is impacting the local ecosystem as well.

“The pollinators, the bees, that come through to pick up the pollen – what's going to happen if peak bloom gets so early that the pollen and the blooms are gone by the time the bees arrive to fertilize them?” questioned Litterest. “It's a long term problem.”

The hundred-year-old trees are also fragile; when the tide comes in twice a day, it overflows the sea wall and salty water from the Tidal Basin seeps into the trees’ roots. Litterest explains the sea wall sunk five feet over the last century, and the water in the Tidal Basin has risen one foot.

“It's a combination of aging infrastructure, we know that it's settled about five feet since it was originally built in the late 19th century, early 20th century. But we also know that the level of the water in the title basin has risen a foot during that same time,” said Litterst. “We've got a net gain of six feet of water that's now going into places that it shouldn't be going.”

“Those roots simply are not hearty enough to withstand that much brackish water on a daily basis.”

Litterst says aging infrastructure and poor drainage are also to blame for the state of the sea wall, endangering the trees. Some of the impacts can already be seen around the tidal basin: over the last few years, Litterest pointed out 14 trees have had to be removed, and debris left from high tide litters the sidewalk and grass.

The good news is that the National Park Service has awarded a $113 million contract to rebuild about 6,800 feet of sea wall along the Tidal Basin. The project, which is funded through the Great American Outdoors Act Legacy Restoration Fund, is scheduled to begin this May and is projected to be completed by 2027. 

It’s a project Litterst says the NPS has been planning for nearly 25 years.

“This area is gonna look very much different starting later this spring, early summer, [and] for the next couple of cherry blossom seasons, in 2025 and 2026, there's going to be a lot of construction activity around here,” he explained. “There are going to be paths that have to be rerouted because of construction, construction fencing.”

According to NPS, the repairs will include:

  • Removing and reconstructing the existing stone masonry seawalls to include a pile-supported platform foundation that will prevent the seawalls from settling, and support height extensions of the walls if needed due to future rising sea levels or increasing storm surge 

  • Salvaging and reusing stones from the historic wall in the rehabilitated seawalls, when possible

  • Repairing, or replacing, and widening walkways around the Tidal Basin to provide smoother, more accessible connections to other pathways

  • Regrading landscaping adjacent to the seawalls as necessary to provide proper drainage.

During the renovation, about 140 cherry trees will need to be removed, but once it’s completed, 274 trees will be planted in their place. NPS says every effort was made to minimize the number of trees that had to be cut down in order to address the growing climate threat to the area.

“We are encouraging people to come down this year, and enjoy the cherry trees before this construction starts,” Litterst said.

Peak bloom for the cherry blossoms is expected to arrive in the coming days in Washington.