The draft study rated the condition of 56 percent of the lakes in the United States as good and the remainder as fair or poor

A draft version of the National Lakes Assessment, the EPA's representative study on lakes under U.S. control will be released tomorrow, Friday, Dec. 18, 2009, the agency said.

Key findings:

• The draft study rated the condition of 56 percent of the lakes in the United States as good and the remainder as fair or poor.
• Degraded lakeshore habitat, rated "poor" in 36 percent of lakes, was the most significant of the problems assessed.
• Removal of trees and shrubs and construction of docks, marinas, homes and other structures along shorelines all contributed to degraded lakeshore habitat.
• Nitrogen and phosphorous were found at high levels in 20 percent of lakes.
• The survey included a comparison to a subset of lakes with wastewater impacts that were sampled in the 1970s. It found that 75 percent showed either improvements or no change in phosphorus levels.

"This survey serves as a first step in evaluating the success of efforts to protect, preserve, and restore the quality of our nation's lakes," said Peter Silva, assistant administrator for the EPA's Office of Water. "Future surveys will be able to track changes in lake water quality over time and advance our understanding of important regional and national patterns in lake water quality."

The study marked the first time the agency and its partners have used a nationally consistent approach to survey the ecological and water quality of lakes. A total of 1,028 lakes were randomly sampled during 2007 by states, tribes and EPA.

Sampling for the National Rivers and Streams Assessment is underway, and results from this two-year study are expected to be available in 2011.

UPDATE 12/18: Study linked below.

Links

• Read the draft study: