WASHINGTON D.C. – The Lincoln Memorial Reflecting Pool has once again been overtaken by a significant algae bloom, just days after the completion of a $14.2 million renovation project. Visitors are reportedly flocking to the iconic landmark to witness the algae-streaked water, with many eager to offer their opinions on potential solutions. The Wall Street Journal highlighted the public's immediate reaction, stating, "People are flocking to see the algae-streaked Lincoln Memorial Reflecting Pool and are eager to weigh in on the solution."
The extensive renovation, ordered by President Donald Trump, aimed to address persistent leaks and algae problems, and included repainting the pool's bottom a specific "American flag blue" in anticipation of the nation's 250th birthday celebrations. However, shortly after the 6.5 million-gallon pool was refilled in early June 2026, green algae began to spread rapidly across the surface.
Experts suggest the new dark blue coating may be exacerbating the issue. Hans Paerl, an algae researcher with the University of North Carolina Institute of Marine Sciences, explained that darker surfaces absorb more solar energy, warming the water and creating ideal conditions for algae growth. Dr. Wayne Carmichael, a biological sciences professor, added that minerals and nutrients left in the system post-refill could also be fueling the bloom.
The Department of the Interior has attributed the initial algae to "residual" material from supply lines that were dormant during the eight-week construction period, describing it as a normal part of the startup process. National Park Service crews are actively working to combat the bloom using hydrogen peroxide treatments and physically vacuuming dead algae from the pool's bottom. The renovation also included the installation of a new "nanobubbler" filtration system, though its effectiveness at this scale remains a subject of expert debate.
Despite the ongoing cleanup efforts, the rapid return of the algae has drawn frustration from visitors and raised questions about the efficacy of the costly renovation. The National Park Service continues its work to restore the pool's pristine appearance ahead of the upcoming July 4th celebrations.
