Chunks of blue paint floating in the water, a green haze spreading across the surface, and a flurry of workers wielding long-handled vacuums—these are not the scenes one might expect at the Lincoln Memorial Reflecting Pool, one of Washington, D.C.'s most iconic landmarks. Yet, in the wake of a $14.2 million renovation spearheaded by President Donald Trump, the pool has become the center of controversy and confusion, just weeks before the city gears up for its grand semiquincentennial celebrations.
The trouble began almost immediately after the pool was refilled in early June 2026. According to NPR, the bottom had been repainted from its original neutral grey to a bold 'American Flag Blue,' a decision that was both highly visible and highly debated. But within days, visitors and reporters alike noticed something was amiss: not only had the water turned an unexpected shade of green, but chunks of the new blue paint were peeling off, floating on the surface and collecting at the pool’s bottom. Photos and videos captured the unsightly scene, prompting questions about what had gone wrong with the expensive facelift.
The National Park Service, tasked with maintaining the pool, quickly found itself battling a familiar foe—algae. The green tint was no mystery to aquatic ecologists. As Dr. Rosalina Stancheva Christova of George Mason University explained to NPR, "The algae belongs to the genus Desmodesmus, and it is growing in excessive amounts, but it is not toxic or harmful." Christova took water samples and confirmed that the conditions in the pool—shallow, stagnant water, ample sunlight, and little shade—were "excellent conditions" for algae growth. She added, "It could happen every single summer. But it seems that the disturbance of the pond during the renovations is accelerating this process."
Indeed, the renovation may have done more than refresh the pool’s appearance. According to swimming pool specialist Steve Goodale, known online as "Swimming Pool Steve," the new, darker interior surface absorbs more sunlight, which warms the water and creates an even friendlier environment for algae. "It's called 'New Pond Syndrome,'" Goodale told NPR. "When you take a natural, clear body of water like this that sits in an open air environment and you try to start it up, very often you end up with green water almost immediately." In this case, the vast size of the pool—2,030 feet long, covering roughly 338,000 square feet—meant the process took a few days to unfold, but the result was the same.
Extreme June temperatures, with heat index values soaring above 95 degrees, likely made matters worse. The Trump administration, for its part, blamed residual material in supply lines that had lain dormant for weeks, while also pointing fingers at previous administrations for not solving the pool’s longstanding algae issues. As an Interior Department spokesperson told NPR over email, "Algae and other contaminants have long plagued the Reflecting Pool since 1922." The spokesperson added, "Unlike under Obama and Biden, the National Park Service is actually maintaining the beautifully completed Reflecting Pool."
But the algae wasn’t the only problem. As The New York Times reported, a business owned by John J. Cafaro, a longtime Trump supporter and donor, was awarded a no-bid $1.7 million contract to install a water-purification system in the pool. Cafaro’s Ohio-based firm, Greenwater Services, set up temporary purification sites and was scheduled to install a permanent system the week of June 15-21, 2026. An Interior Department spokesperson insisted the firm was chosen "because they had the expertise, workforce and materials," and denied knowledge of Cafaro’s political connections.
The Trump administration’s response to the algae was swift and multi-pronged. Workers poured containers of 12% hydrogen peroxide into the water—a treatment the Interior Department described as "milder than chlorine and used in spas and specialty pools like natural swimming pools." The department assured the public that "there are no harmful side effects to marine life or to the environment." Alongside the peroxide, workers deployed what officials called "high-tech nanobubble ozone technology" to neutralize algae and other pathogens. According to Goodale, these ozone bubbles are so tiny they can last weeks or even months in the water, continuously oxidizing contaminants and "keeping the algae at bay."
Despite these efforts, as of June 18-19, much of the pool remained stubbornly green. Crews continued to vacuum up dead algae with mobile systems known as "trash pumps," while orange cones and humming machinery marked the ongoing work zones. Passersby seemed largely unfazed, some snapping photos of the green water and peeling paint, others focusing on the Washington Monument rising in the background.
The renovation project itself has drawn scrutiny, not just for its cost—ballooning from an initial $2 million estimate to at least $14 million—but also for its design choices. Last month, the Cultural Landscape Foundation, a nonprofit dedicated to preserving historic landscapes, sued the Trump administration in federal court over the repainting. The group argued that the blue tint was "blatantly unlawful" and that the original dark grey floor was a deliberate design choice, intended to create the "illusion of greater depth and a more profound reflection." As the foundation’s president, Charles Birnbaum, put it, "A blue-tinted basin is more appropriate to a resort or theme park." The suit seeks to block the repair work and restore the pool to its original color.
Meanwhile, President Trump and Secretary of the Interior Doug Burgum have touted the renovation as a major success. In a May post on Truth Social, Trump wrote, "The scope of the Project has been greatly enlarged as we became involved because we realized how important it would be to Washington, D.C., and the record number of visitors coming to our now very safe Capital for all of the upcoming events in celebration of our 250th Anniversary." The National Mall is set to host a slew of semiquincentennial events around July 4, including a weekslong state fair kicking off June 24.
But for some, the ongoing algae battle raises questions about whether the renovation addressed the pool’s underlying problems. Civil engineer Loay Hidmi, who specializes in water treatment, has visited the pool all week to track the progress. "I'm taking pictures of it for the last week and I can see the gradual change," he told NPR. "So I'm hopeful. But we'll have to see if it gets sustained." Hidmi worries that the algae could return, given the favorable conditions, and wonders if the process overlooked key steps. "In water systems, when you fix something, you need to look at the step before it and the step after."
Goodale agrees that eliminating algae is only part of the solution. "That's like the equivalent of mowing the lawn when perhaps it needs to be something else that addresses the source nitrates and phosphorus, so that it's more like pulling the weeds out by the root," he explained. Even after the Obama-era renovation, the pool suffered from broken pipes and water leaks, requiring costly refills and ongoing maintenance. The Department of the Interior’s 2023 report called for new expansion joints and an improved distribution system to ensure proper water circulation and treatment.
For now, the algae doesn’t seem to bother the ducklings swimming in the pool—nor, it seems, the majority of tourists. As the city prepares for its historic celebrations, the Reflecting Pool remains a symbol not just of national memory, but of the ongoing challenges of preserving the past amid the realities of the present.