Over a five-year period, the country’s number of blue lakes declined by 18 percent, while murky lakes increased by 12 percent.

In 2007, blue lakes represented 46 percent of the freshwater bodies included in the Environmental Protection Agency’s National Lakes Assessment (NLA). By 2012, this figure had dropped to 28 percent; at the other end of the spectrum, the percentage of murky lakes skyrocketed from 24 percent to 35.4 percent.

Stephanie Hampton.

Researchers from the EPA, Virginia’s Longwood University, and Washington State University relied on NLA data to evaluate the current state of America’s lakes and, according to a press release, assess encroaching murkiness’ “potential negative consequences for water quality and aquatic life.” The team, which includes WSU environmental studies professor Stephanie Hampton, recently released their findings in Limnology and Oceanography.

Color can reveal information about a lake’s nutrient load, algal growth, water quality and surrounding landscape.

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