The mystery of the green water in Washington’s famous pool

A Stunning Transformation

One of the nation’s most iconic landmarks—the massive reflecting pool near the Lincoln Memorial in Washington—has taken on an unexpected hue: a murky shade of green. What was supposed to be a routine upgrade to fix leaks and refresh the water’s appearance has instead turned into a recurring nightmare of algae blooms.

The Failed Fix

Taxpayers funded a $15 million resurfacing project and an additional $1.7 million for water treatment, but the green menace persists. Experts point to three critical factors fueling the algae’s relentless growth:

• Nutrient overload (nitrogen and phosphorus from runoff)
• Unfiltered sunlight (shallow depths allow light to penetrate easily)
• Warm water (dark blue paint may accelerate heating)

Why Temporary Solutions Fail

Quick fixes like hydrogen peroxide provide only short-term relief. When algae die, they decompose and release nutrients back into the water, sparking new blooms. Long-term solutions—such as advanced filtration or chemical treatments—are needed, but they come with hefty price tags.

A Century of Struggles

This isn’t the first time algae has plagued the pool. Records dating back to the 1920s show a long history of green outbreaks. Over the decades, officials have oscillated between cheap patchwork repairs and costly overhauls, often with mixed results.

Political Fallout & Finger-Pointing

The pool’s persistent problems have sparked political debates. Some blame vandalism, while others argue rushed, low-cost methods were a mistake. With no permanent fix in sight, the iconic pool remains under scrutiny—and under green.