Tetra Tech is providing expertise and technical support to the U.S. Environmental Protection Agency (EPA) to assess the ecological condition of aquatic resources across the United States.

The National Aquatic Resource Surveys are national-scale, collaborative efforts among the states, tribal nations, EPA, and other federal agencies. These statistically valid surveys of the condition of streams, rivers, lakes, coastal waters, and wetlands throughout the United States will help evaluate the success of national and regional efforts to protect and restore water quality.

Statistically representative surveys of the aquatic resources of the United States have begun providing us with the information we need to identify national priorities and evaluate the effectiveness of pollution control actions. These assessments report on core indicators using standardized field and lab methods and include a national quality assurance program. The surveys are designed to yield unbiased estimates of the condition of a whole resource, based on a representative sample of waters.

EPA Progress Report on the National Aquatic Resource Surveys
Tetra Tech scientists provided key technical and logistical support for the Wadeable Streams Assessment (2005), National Lakes Assessment (2006 and 2012), National Rivers and Streams Assessment (2008–2009 and 2013-2014), National Coastal Condition Assessment (2010 and 2015), and National Wetlands Condition Assessment (2011). Tetra Tech’s expertise has been paramount to EPA to successfully carry out this project. Tetra Tech’s role includes developing indicators and methods, training field crews, providing field sampling crews, tracking the progress of various aspects of the surveys, and processing samples.
 
The surveys required collecting samples from more than 1,000 sites each year. Depending on water body type, sampling indicators include water, benthic macroinvertebrates, fish, diatoms, vegetation, soil, sediment, physical habitat quality, and field chemistry. Tetra Tech has provided laboratory support for several of the surveys and has provided strong quality control oversight for field and lab procedures.
 
The data is analyzed and a report issued on the condition of the water resources within two years of sampling. A report to Congress on the condition of water resources throughout the United States is scheduled for every two years. Tetra Tech holds a contract covering technical and logistical support for the surveys for the next five years.