Overview
- The Reflecting Pool, refilled in early June, developed visible clumps of green algae days after contractors finished a rushed renovation that repaved the basin and added filtration equipment.
- The Department of the Interior said the installed 'advanced nanobubbler' ozone system killed the algae and crews were vacuuming dead material, while videos and reporters showed National Park Service staff also pouring hydrogen peroxide into the water.
- Federal contracting records and reporting show the expedited, no‑bid project ballooned from initial low estimates to roughly $13–$14 million overall, including about $1.7 million for the upgraded ozone/nanobubbler system.
- Experts and officials note the work applied a dark blue waterproof coating but did not fully replace aging underground circulation pipes that feed the pool, and the Interior plans separate pipe repairs in the fall.
- Preservation groups sued over changes to the pool's historic appearance, a judge allowed work to proceed, and officials face questions about oversight, long‑term maintenance costs and whether treatments will prevent repeat blooms before July 4.