Even after $16 million worth of renovations were completed on the Lincoln Memorial Reflecting Pool, the green algae first spotted over the weekend has remained.

A business tied to a longtime supporter of President Trump was given a no-bid contract to install a water-purification system in the Lincoln Memorial Reflecting Pool earlier this spring.

On Thursday, a sheet of the pool’s surface — painted in “ American Flag Blue, ” a color selected by the president — was seen floating in the water on the north side of the pool.