The Lincoln Memorial Reflecting Pool in Washington, D.C., turned green this week due to an algae bloom [1, 2, 3].
The incident is particularly notable because the discoloration occurred only days after the completion of an extensive renovation [1, 3]. The pool serves as one of the most photographed landmarks in the U.S., often reflecting the image of the Abraham Lincoln statue during national protests and celebrations.
Officials said the algae proliferated because of specific conditions following the renovation work [3, 4]. The project to restore the pool cost $14 million [1].
To combat the bloom, maintenance crews began treating the water with hydrogen peroxide [3, 4]. Officials said they introduced tiny bubbles into the water to aerate the pool and disrupt the growth of the algae [3, 4].
This is not the first time the pool has faced water quality issues, but the timing of this bloom, occurring immediately after a multimillion-dollar investment, has drawn public attention [1, 3]. The aeration process and chemical treatment are intended to return the water to its clear state quickly [4].
“The Lincoln Memorial Reflecting Pool in Washington, D.C., turned green this week due to an algae bloom.”
The rapid development of an algae bloom following a high-cost renovation suggests that the chemical balance or water circulation of the pool was destabilized during the construction process. While the use of hydrogen peroxide is a standard remedy for algae, the incident highlights the difficulty of maintaining artificial water bodies in urban environments where temperature and nutrient runoff can trigger sudden biological growth.
