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A Monitoring and Assessment Program for the Great Rivers: EMAP’S Great River Ecosystems Assessment

David W. Bolgrien 1, Brian H. Hill 1, Ted R. Angradi 1, Larry Shepard 2, Terri M. Jicha 1, Mark S. Pearson 1, Debra M. Taylor 1, Mary F. Moffett 1, Sharon L. Batterman 1, Leroy E. Anderson 1, Colleen M. Eloenen 1, William Franz 3

1 U.S. Environmental Protection Agency (USEPA), Office of Research and Development
2 U.S. Environmental Protection Agency, Region 7
3 U.S. Environmental Protection Agency, Region 5

Ecological assessments of Great Rivers are challenged by rivers’ expansiveness and multi-jurisdictional character, and assessment strategies that inadequately incorporate biological indicators and characterize reference conditions. The U.S. Environmental Protection Agency’s Environmental Monitoring and Assessment Program for Great River Ecosystems (EMAP-GRE) is addressing these challenges by analyzing physical, chemical, and biological data from the Mississippi, Ohio, and Missouri Rivers. Not only is our program improving the science of Great River assessments, it can improve the practice of river assessment, typically to support Section 305(b) of the Clean Water Act. However, inventorying water quality does not take full advantage of the EMAP approach. In addition to describing the technical aspects of EMAP-GRE, we will discuss the potential for re-purposing its outputs for adaptive management, restorative and sustainability-based management efforts, and estimating ecosystem services. Like the Clean Water Act, these efforts depend on unbiased assessments of ecological condition. We used probabilistic sampling designs and consistent methods to estimate the nature, range, and extent of conditions across the rivers. Reference conditions are characterized as least-disturbed based on abiotic indicators (e.g., proximity to habitat disturbances, water quality, and exposure of fish to organic contaminants). Initial analyses found that 30-40% of the Upper Mississippi River are in least-disturbed conditions based on native fish species richness and the proportion of intolerant fish species. Reference conditions may have to be stratified to account for natural gradients or habitat classes. Our empirical assessment approach based on least-disturbed conditions, rather than historical, pristine, or desired conditions, is appropriate for Clean Water Act reports. However, it may not satisfy the needs of adaptive management, river restoration, or ecosystem services evaluations.

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