Workers dumped containers of 12% hydrogen peroxide into the Lincoln Memorial Reflecting Pool on Monday, beginning a cleanup meant to knock back an algae bloom that had turned the landmark green.
The Department of the Interior said the chemical is a milder treatment than chlorine and is used in spas and specialty pools such as natural swimming pools, adding that it would have no adverse effect on wildlife that use the pool. By Tuesday, aerial photos showed signs the algae was dissipating from the sides of the pool, though it remained clumped together in the center.
The treatment came after the Reflecting Pool, first installed in 1922, had again become a problem for visitors and officials watching one of Washington's most photographed landmarks. The federal government had already spent about $14.2 million on renovations to the pool, well above the roughly $1.5 million Trump initially said the project would cost.
That spending has been part of a broader dispute over how the pool should look and how much should be spent to keep it that way. Trump announced the renovations in April and said at the time that he wanted the basin to be American Flag Blue, while Obama spent about $34 million on work there in 2012.
The algae has been a recurring problem for years, and the department previously blamed the resurgence on residual algae in supply lines that bring water to the pool from the Tidal Basin. Katie Martin said Monday that the administration was using nanobubbler technology and said it had successfully destroyed the algae bloom that had plagued every pool reopening since 1922.
The immediate question is how far the treatment goes. The latest photos suggested the peroxide was already breaking up the bloom at the edges, but the center of the pool was still green, leaving the long-term fix for the hydrogen peroxide reflecting pool unresolved.
