Did the Reflecting Pool remodel cause the bright green algae bloom?

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(NEXSTAR) – President Trump’s vision was to paint the Lincoln Memorial Reflecting Pool a darker shade of “American flag blue” to celebrate the country’s 250th birthday. But this week, it’s been looking more green.

The Washington, D.C., pool has turned a shade of green thanks to an algae bloom that appeared just days after the $14 million renovation wrapped up.

“What do you expect?” said Cochise Wanzer II, president of the Pool Service Company in Arlington, Va., in an interview with the Associated Press. “You’re basically taking natural, untreated river water, pumping it in and expecting it to do something different from what it would do out in the open.”

The Reflecting Pool typically gets its water from a basin nearby that is often filled with algae, WIRED reports. However, during periods of algae activity, like when the weather warms up, the supply is supposed to switch over to another clean source.

The pool’s new shade of “American flag blue” may have also made conditions rife for a big bloom, Wanzer suspected. “Now that the bottom is nice and dark, it elevates the temperature and the algae grows better.”

The Interior Department told CNN the algae appearance is “part of the normal startup process.”

“What you are seeing is residual algae from the supply lines, which have been sitting dormant for eight weeks while construction has been taking place,” said communications director Kate Martin.

Nexstar reached out to the Interior Department for more details on what factors led to the algae bloom but didn’t hear back by publication time.

The pool’s filtration has long been a problem, said Kym Hall, a former regional director of the National Park Service, in an interview with Politico. “I’m not sure how this administration thought they were going to somehow overcome a long-standing challenge of keeping [the pool] clear (not to mention wildlife contributing waste to the water) by painting it.”

Teams of National Park Service employees and contractors are deploying chemicals and ozone nanobubbles to keep the algae in check, not dissimilar from efforts to clean the pool before Trump’s renovation kicked off. Workers have also been using a swimming pool-type vacuum cleaner to suck up algae from the bottom.

The park service said in a statement that crews also using hydrogen peroxide, a milder treatment than chlorine and one used in spas and natural swimming pools. “There are no harmful side effects to marine life or to the environment,” NPS told the AP.

The Associated Press contributed to this report.

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America 250

American-flag blue

Donald Trump

Kate Martin

Lincoln Memorial Reflecting Pool

National Mall

National Park Service

Reflecting Pool

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