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National Aquatic Resource Surveys

National Wetland Condition Assessment 2011 Results

The NWCA 2011 is the first national assessment of the ecological condition of the nation’s wetlands.

Key Findings

  • Nearly half of wetland area (48%) is in good condition; 32% is in poor condition and the remaining 20% is in fair condition.
  • Physical disturbances to wetlands and their surrounding habitat such as compacted soil, ditching, and removal or loss of vegetation, are the most widespread problems across the country. Wetlands with high levels of compacted soil are about twice as likely to have poor plant communities.
  • Nonnative plants are a problem across the country, particularly in the interior plains and west. 46% of wetland area in the interior plains and 72% of wetland area in the west have high or very high levels of stress from nonnative plants.