National Wetland Condition Assessment

What is the National Wetland Condition Assessment?

The National Wetland Condition Assessment (NWCA) is the first-ever national survey of ecological condition of the Nation's wetlands and is one of the five National Aquatic Resource Surveys initiated in 2006. These studies provide nationally-consistent and scientifically-defensible assessments of our lakes, rivers, wadeable streams, coastal waters, and wetlands, and can be used to track changes over time. One of the purposes of the survey is to report to Congress on the condition of the Nation's wetlands with data that are statistically valid and environmentally relevant. The study is the product of cooperation and collaboration between the U.S. Environmental Protection Agency (EPA), Natural Resources Conservation Service, state natural resource managers, and scientists. EPA provides the funding for the study and states often conduct the fieldwork and provide expertise to complete the assessment.

The NWCA is being used to:

  • Determine the national & regional condition of wetlands (NWCA findings are not state-specific)
  • Develop baseline information to evaluate change in condition over time
  • Build state and tribal capacity for monitoring and analyses.

Results and findings from the NWCA are not used by EPA or the state to provide state-level information or for regulatory purposes in Washington. Data from sites in Washington contribute to the national averages for condition among different wetland types and regional averages for the western states.

The 2011 National Wetland Condition Assessment was the first national evaluation of the ecological condition of the nation’s wetlands. The field sampling for the second evaluation will be conducted in 2016. In 2011, Washington Department of Ecology wetlands staff participated in the survey and will also participate in 2016. Of the 1,138 sites nationwide, a total of 15 wetland sites were selected by the EPA for assessment in WA in 2011. In 2016 Ecology will be sampling 30 wetland sites in Washington.

More Information


If you have any questions about the NWCA survey in Washington, contact Amy Yahnke at 360-407-6527 or

Navigating to a wetland site in 2011.  A palustrine, emergent riverine flow-through wetland.

Collecting data along a transect in a freshwater emergent wetland.

Collecting soil samples at an estuarine intertidal wetland.

Setting up the assessment area at a wetland in eastern Washington.


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