Crews poured hydrogen peroxide into the Lincoln Memorial Reflecting Pool this week to eliminate a massive algae bloom that turned the water green [1, 2].
The incident is significant because the bloom appeared shortly after the completion of an expensive infrastructure project intended to maintain the landmark's appearance. The recurrence of the algae raises questions about the efficacy of recent maintenance efforts in the nation's capital.
National Park Service workers used gallon jugs of hydrogen peroxide to treat the water [3]. Officials said the algae bloom was targeted because it could pose a risk to wildlife [1, 4]. The chemical treatment was deployed to clear the water and restore the pool's reflective quality.
This biological surge occurred only days after a $14 million [5] renovation of the reflecting pool. The project included repainting the basin to improve its durability and aesthetic [6]. Despite the investment, the water quality deteriorated rapidly in mid-June [6].
National Park Service officials said they are investigating the cause of the green water [7]. While some reports confirmed the use of hydrogen peroxide, other initial accounts questioned if the chemical had been deployed as officials continued their investigation [8].
The pool serves as a central focal point for the National Mall, often hosting large crowds and historic events. The visibility of the algae bloom drew immediate public attention, prompting the rapid response from maintenance crews to prevent further ecological or visual damage.
“Gallon jugs of hydrogen peroxide were dumped into the Lincoln Memorial Reflecting Pool.”
The rapid return of algae following a $14 million renovation suggests that structural repairs alone may not address the underlying biological or chemical imbalances of the pool's ecosystem. The use of hydrogen peroxide is a common remediation tactic, but the timing of the bloom indicates a potential failure in the new maintenance protocols or an unexpected environmental trigger in Washington, D.C.
