The Lincoln Memorial Reflecting Pool in Washington, D.C., has turned a murky green despite a $14.8 million renovation project intended to restore its appearance. According to the National Park Service, the discoloration is due to residual matter in supply lines and the natural behavior of untreated water, while officials continue to deploy ozone nanobubble technology to mitigate algae growth.
Why is the Reflecting Pool turning green?
The emergence of algae in the Reflecting Pool is a recurring maintenance challenge for the National Park Service. According to Cochise Wanzer II, president of the Pool Service Company in Arlington, Va., the pool essentially acts as an open-air basin for natural, untreated water. When pumped into the monument, this water naturally supports algae growth. Wanzer notes that the choice of a dark blue paint for the pool floor may have worsened the issue by absorbing more heat, which creates a more favorable environment for algae to thrive.
The Lincoln Memorial Reflecting Pool has struggled with water quality issues since its completion in 1922. Maintenance crews have historically used various filtration methods to combat the growth of algae and pathogens like E. coli.
How does the current project compare to previous efforts?
The scale and framing of the recent renovation have sparked debate regarding federal spending and project efficacy. While the U.S. Department of the Interior stated that the current administration is maintaining the pool “unlike under Obama and Biden,” records indicate varying approaches to the monument’s upkeep.
| Administration | Claimed/Reported Context |
|---|---|
| Trump | $14.8 million renovation; usage of ozone nanobubbles. |
| Obama | Multimillion-dollar renovation; cited by current officials for past algae issues. |
The Department of the Interior stated in an X post that their current nanobubble technology is “very effectively” killing algae. However, federal spending records show the actual costs of the current project are higher than the figures initially cited by President Trump.
What happens next for the monument’s upkeep?
National Park Service contractors are currently vacuuming dead algae from the pool floor while maintaining the chemical treatment cycle. The use of ozone nanobubbles is intended to kill pathogens and contaminants that have plagued the site for decades. According to the Department of the Interior, this high-tech approach represents a shift in how the agency manages the 2,000-foot-long structure.
Monitoring official U.S. Department of the Interior press releases is the most reliable way to track updates on the status of national monuments and federal maintenance projects in Washington, D.C.
Frequently Asked Questions
Is the water in the Reflecting Pool safe?
The National Park Service reports that they are deploying technology to kill pathogens such as E. coli. The pool is not intended for swimming or human contact.
How much did the recent renovation cost?
Federal records confirm that contracts for the project were worth at least $14.8 million.
Is this the first time the pool has turned green?
No. According to the U.S. Department of the Interior, algae has plagued the pool since it first opened in 1922.
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