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Supplemental Module: Monitoring and Assessment

This module covers the role of monitoring and assessment in the implementation of clean water programs, including reporting on the condition of the Nation’s waters and meeting the fishable/swimmable goals of the Clean Water Act.

Water quality monitoring should be the scientific foundation for the implementation of Clean Water Act programs. Monitoring supports States/Tribes in developing and refining water quality standards, reporting on water quality conditions, listing impaired waters, issuing and enforcing discharge permits, managing nonpoint sources, protecting good quality waters, setting priorities for water quality management, tracking changes in water quality over time, and evaluating the effectiveness of restoration and protection actions. The Clean Water Act assumes monitoring is fundamental to all CWA programs, and makes an adequate State/Tribal water monitoring program a prerequisite for receiving Section 106 grants for administering water pollution control programs.

This module provides basic information on the following:
  • Why is an integrated monitoring program that includes different monitoring designs needed to support multiple clean water programs?
  • What are the critical elements of a monitoring and assessment program?
  • What resources are available?

At the end of the module is a brief quiz intended to touch on aspects of water quality monitoring and assessment. The topic is further examined in the classroom session of this module.

This module's main pages and brief quiz at the end take about 25 minutes to complete. 

Importance of an Integrated Monitoring Program

Under the Clean Water Act, States, Tribes, and Territories have the primary responsibility for monitoring and assessing their waters and reporting on water quality. Long-standing critiques by the Governmental Accountability Office, National Research Council, National Academy of Public Administration, and other independent organizations have found that the Nation and the States/Tribes do not have all the monitoring data needed to effectively manage their water programs. Different monitoring approaches are necessary to make scientifically defensible statements about the condition of waters, track changes, and manage water quality protection and restoration at multiple geographic scales.

Under traditional monitoring approaches, States/Tribes have assessed approximately 20 percent of their streams and rivers, 40 percent of lakes, and 30 percent of bays and estuaries. States/Tribes have generally used a site-specific, targeted monitoring approach because it allows them to focus limited monitoring resources on heavily used or problem waters.

Water quality standards and the methods used to monitor and assess waters vary across States and Regions. Often indicators, parameters, and sampling procedures vary across States/Tribes, and sometimes within them. Methods to determine the spatial extent of the assessment (e.g., ¼ mile or 25 miles downstream) also vary. While this approach is consistent with the Clean Water Act and may be appropriate for management of State/Tribal waters, it complicates the process of generating a regional and national picture of water quality and addressing water quality concerns affecting regional and interstate waters.

Key Point. States should strive to integrate different monitoring approaches and coordinate monitoring activities across the State/Tribe, Region, and Nation to provide data for as broad a range of clean water programs as possible. 

EPA issues guidance for use by States/Tribes in implementing their monitoring and assessment programs.

Resource. Additional guidance is available at EPA’s webpage on Monitoring and Assessing Water Quality.

Resource. See also EPA’s webpage on the Consolidated Assessment and Listing Methodology (CALM)

Learn More. There are a number of provisions in the Clean Water Act that drive State/Tribal water quality monitoring and assessment. Proceed to the Learn More Topic.

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Disclaimer: This online course presentation and any associated links have been prepared by EPA staff for informational purposes only. Their sole purpose is to make available training online from recent Water Quality Standards Academy classroom courses. As such, this online course and any associated links are not binding on EPA or the public and have no legal effect. They do not constitute an EPA statute, regulation or other requirement and do not substitute for such authorities. In addition, the course and any associated links have not been reviewed or endorsed by EPA management. Thus, they are not intended or written as official statements of EPA's scientific views, policies, guidance, or requirements and cannot be used or cited as evidence of EPA's position on any matter.