The roots of Washington, D.C.’s iconic cherry trees are rotting. At the National Mall Tidal Basin, where cherry trees line the water’s edge amid some of the country’s most famous monuments, sea-level rise and riverine flooding threaten not just tree roots but a landscape inextricably tied to the history of the United States. If the situation is left unaddressed, rising waters could inundate the trunks of those cherry trees along with monuments to figures such as Martin Luther King Jr., Thomas Jefferson, and Franklin Delano Roosevelt in several feet of water every day during the river’s twice-daily high tides.
A new initiative is offering potential solutions. The Tidal Basin Ideas Lab has hired five landscape architecture firms to reimagine this flood-prone landscape. An online exhibition of these ideas is hoping to show how this endangered site can persevere—and to solicit the public support to convince Congress to fund its rescue.
Washington, D.C., is experiencing compounding effects of climate change, with its land sinking and its waters rising, creating ongoing challenges for the tidal basin and its developed edges. “The most basic problem is it’s breaking up the pavement, and within time, the monuments will be underwater,” says Donald Albrecht, cocurator of the exhibition. By 2040, the Jefferson Memorial could be under four feet of water every day. By 2070, the MLK memorial could be in six feet of water at high tide. The cherry trees don’t stand a chance.
Launched by the National Trust for Historic Preservation, the Trust for the National Mall, and the National Park Service, the Tidal Basin Ideas Lab is looking beyond flood mitigation and engineering solutions for what Albrecht calls more “visionary and speculative” designs. “They decided to hire landscape architects who think more regionally, ecologically, historically, culturally—who think big, in other words,” he says.
With funding from American Express, the Ideas Lab solicited proposals from DLANDstudio, GGN, Hood Design Studio, James Corner Field Operations, and Reed Hilderbrand, some of the most prominent landscape architecture firms working today. Their proposals range from creating large landforms and moving memorials to reshaping the space with elevated walkways to using the landscape to tell a deeper story about American history. The designs confront the flooding and natural changes coming to the site while also preserving its historical significance, according to cocurator Thomas Mellins.
“The larger narrative is that cultural and aesthetic and ecological concerns are no longer seen as distinct entities that don’t relate to each other. Landscape architects today are thinking of those components as a seamless whole. And every intervention that they make they are thinking about its impact on each one of those realms,” says Mellins.
He points to the proposal by Brooklyn-based DLANDstudio, which would preserve the MLK statue by moving it onto a raised jetty that stands in direct alignment with the Abraham Lincoln Memorial—a flood protection intervention that also serves to draw a clear connection between the racial and civil rights accomplishments of these two figures.
The proposal from Oakland-based Hood Design Studio tells the lesser-known history of the tidal basin site, using a new walkway to highlight sections of the basin that would have served as “hush harbors,” or places where enslaved people could hide from plantation owners and find a sense of independence. Though only a temporary reprieve in the times before the signing of the Emancipation Proclamation, these spaces were integral to the founding of Black churches.
GGN, based in Seattle, proposes a series of gradually implemented earthworks to serve as flood protection for the city, as well as adaptations or relocations that will protect the monuments at the site.
Using the original 1902 plan for the National Mall as its inspiration, Cambridge-based Reed Hilderbrand reframes the tidal basin as a core element of a regional system of parks and green spaces, creating a “Washington Commons.”
There are three alternatives in the proposal from James Corner Field Operations, including one that suggests simply allowing the flooding to happen and leaving the monuments in their places as a way to reveal the consequences of inaction.
All five firms’ proposals include ways to save the popular cherry trees as well. Their designs are included in an online exhibition, along with videos explaining their concepts and visions for the future of the site. The exhibition also includes surveys and feedback areas where the public can share opinions on the designs. Though originally planned for display at the National Building Museum, the exhibition will be entirely online—which may actually be a better way of soliciting public feedback from a wide audience, the curators say. The organizers hope to use that feedback to convince Congress to fund an intervention based on some or all of these design concepts.
The exhibition was in the works long before recent protests over systemic racism brought attention to memorials around the country, but curators Albrecht and Mellins say those events have given the design concepts another layer of relevance.
More people are now thinking about “what should a public place be, and to the extent that it reflects our national history, who gets to decide what that story is,” says Mellins. “The very nature of these places is being reconsidered now as a national dialog of what our history is all about.”