Reflecting Pool woes: Trump administration turns to hydrogen peroxide in latest bid to beat back algae

By Sunlen Serfaty, Kit Maher, Dugald McConnell, CNN

(CNN) — President Donald Trump’s more than $14 million Lincoln Memorial Reflecting Pool renovation was completed just over a week ago, with its iconic 2,800 square feet refilled with 6.5 million gallons of clean water.

But already it’s been hit with a problem that has haunted administrations for decades: algae.

Over the past week, the Trump administration has jumped into action, sending crews clad in hip-waders to vacuum up the clumps of algae and on Tuesday, dispatching workers to dump gallons of hydrogen peroxide in the pool.

Nevertheless, the pool has grown increasingly into a murky shade of green – calling into question whether the president’s goal of cleaning and beautifying a pool he once disparaged as “disgusting” and “not representative of the country” can ever really be met.

A worker who spoke to CNN on Tuesday quipped that it would take “an entire lifetime” to clean the pool.

The Department of Interior says “state of the art” filtration known as the “ozone nanobubbler” has been installed and is working.

“Due to deploying the advanced nanobubbler technology, the algae is dead and being vacuumed up as we speak,” a Department of Interior spokesperson told CNN. “The nanobubbler technology has successfully destroyed the algae bloom that has plagued every pool reopening.”

The spokesperson also told CNN that hydrogen peroxide is being used as a “milder treatment” for algae in addition to the nanobubbler, adding that it has “no harmful side effects to marine life or to the environment.”

Other parties involved with the Reflecting Pool’s refurbishing distanced themselves or stayed mum on the algae problem.

“My company had nothing to do with water, only water proofing and water tightening,” Eddie Wood, of Atlantic Industrial Coatings, the company that resurfaced the pool, told CNN. He added that he is proud of the part of the work his company did on the project.

Public records show that an Ohio company, Greenwater Services, was hired to install the filtration system. Its website boasts that the company provides “the only water purification system in the world whose patented technology is backed by government and academic research” and that its “breakthrough solutions significantly reduce toxins, algae, microcystins, nitrates, and phosphates from contaminated water.”

The company did not return CNN’s request for comment about the current algae situation.

The White House did not comment on whether Trump is aware of cleanup efforts, surprised by the presence of algae or has spoken to Interior Secretary Doug Burgum about it, directing questions back to the Interior department.

A growing green hue

The issues seemed to have started almost immediately after the Reflecting Pool was refilled last week.

One day after fresh water had been put in, CNN first reported the presence of algae – in some areas, it could be seen from the water’s edge on the bottom of the pool. One worker who was wading in the water, vacuuming, told CNN the substance was algae.

When asked initially, a spokesperson for the Interior Department said its Fish and Wildlife Services department wasn’t convinced it was algae.

A few hours later, the department followed up to say the substance was “residual algae from supply lines,” which had been dormant during the eight weeks of construction.

“It’s part of the normal startup process. We are removing the algae, and the nanobubblers will maintain the pool and keep it algae free,” communications director Kate Martin said in a statement last Wednesday.

When CNN independently took a sample of the water last Wednesday and consulted with a pool store that regularly tests water to help read the results, it showed phosphate levels far higher than what is recommended to keep algae at bay based on estimates for a pool that holds 6.5 million gallons of water. CNN obtained another test Tuesday that showed the phosphate levels had dropped but were still elevated.

Phosphates are a primary nutrient for algae, and high levels make algae growth more likely.

Last week, a department official said they would provide a firmer deadline on when the “residual algae” would be removed, saying they didn’t want to speculate on timing due to the forecasted rain.

But CNN has not received an updated answer on when the algae is expected to be cleared.

And the Reflecting Pool only grew greener over the weekend.

Tim Auerhahn, chairman of the Aquatic Council, a consulting firm, told CNN that if underlying conditions for algae growth stay the same, “it’s reasonable to expect continued algae presence throughout the summer and into the fall.”

“In a body of water this large, that can become an ongoing maintenance challenge,” he said.

Past is Precedent

To be sure, the Reflecting Pool has faced algae problems before.

In 2012 the Obama administration spent $34 million and 18 months restoring the pool, and within a month, it was filled with algae, collecting bird droppings and drawing criticism from tourists.

“It smells like a wet dog down there, you know. When my dog came home from the stream, he always smelled like this,” a tourist told CNN in 2012. “It’s gross.”

Around that time, the National Park Service said approximately 80 ducks were found dead in the Reflecting Pool within a two-day period.

The pool was only cleaned out a few times a year and did not have a filtration system.

Now Trump administration officials say the Obama-era efforts also failed to resolve larger issues with the pool, claiming that it was still leaking 16 million gallons of water a year.

“Most infamously, the Obama pool reopening that resulted in massive algae clumps taking over the pool’s surface following years of construction that cost taxpayers millions upon millions only to be broken and disgusting days later,” an Interior department spokesperson said.

Trump has put extensive focus on the project, as he made the beautifying of the pool one of his personal priorities to be expedited and completed in time for the nation’s big 250th celebration over July 4.

“There’ll be no leaks. There’ll be no anything. It’ll look gorgeous, beautiful,” Trump said in April after driving onto the Reflecting Pool in his motorcade to survey the work being done with the Interior Secretary.

Administration officials acknowledged to CNN the expedited timeline had driven up the cost, which rose from an initial estimate of $1.8 million to more than seven times that. The latest estimate according to a website that tracks government spending is $14.2 million.

In addition to the functional fixes to the pool, the president ordered cosmetic changes – most notably painting the pool from the dull gray to the bright “American Flag” blue color, which received pushback from historians and preservationists.

Administration officials said dark color was intended to improve the reflection qualities of the pool.

By adding the nanobubbler filtration system, fixing the leaks, and adding a dedicated crew from the Fish and Wildlife Service to maintain the grounds, the Interior Department intends to bring permanent fixes and a cleaner experience to the Reflecting Pool.

The “high-tech nanobubble ozone technology” is “actively killing algae, pathogens (e.g., E. coli), and contaminants that have long plagued the Reflecting Pool since 1922,” the department spokesperson said.

But Barett Brooks, who is an algae specialist and works in the Botany Department at the Museum of Natural History, warned that while “the ozone treatment looks good on paper” and “should work if they continue to do it,” it will require continued maintenance.

“It would be an ongoing filtration management thing going on. It’s not like, oh, we’re going to treat it; it’ll be good for three months; we’ll get you through the summer,” Brooks said, noting that the pool’s depth combined with Washington’s warm weather create perfect conditions for algae blooms. “If it kills all the algae that’s in there, that’s all nutrients for the next round.”

The current algae bloom, he noted, “has been particularly big.”

CNN’s Christine Lien and Abigail Roedersheimer contributed to this report.

This story has been updated with additional information.

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