

Large algae blooms in lakes and rivers have become an annual warm weather headache in nearly every U.S. state, endangering water supplies and local economies. A new competition hopes to help.
(Image credit: Greg Allen/NPR)
Large algae blooms in lakes and rivers have become an annual warm weather headache in nearly every U.S. state, endangering water supplies and local economies. A new competition hopes to help.
(Image credit: Greg Allen/NPR)