The National Water-Quality Assessment (NAWQA) Program is designed to describe the status and trends in the quality of the Nation's surface-water and ground-water resources and to provide a sound understanding of the natural and human factors that affect the quality of these resources. As part of the program, investigations will be conducted in approximately 60 areas -- called study units -- throughout the Nation to provide a framework for national and regional water-quality assessment. National and regional synthesis of information from study units will consist of comparative studies of specific water-quality issues using nationally consistent information.

    The Mississippi Embayment (MISE) Study Unit is one of 15 Study Units that began in 1994. Surface-water, ground-water, and ecological data collection took place in the MISE area in 1996, 1997, and 1998. Data collection has continued at a smaller number of sites and at a lesser frequency than during the 1996-98. Data collection for the first intensive phase was completed during August 1998, and analysis and synthesis has been completed with a number of publications from Study Unit staff and other collaborators.

   In 2001, the U.S. Geological Survey's National Water-Quality Assessment Program began its second decade of intensive water-quality assessments. NAWQA scientists will return to 42 of the original study units that were assessed during NAWQA's first decade; 14 began in 2001, another 14 in 2004, and a final 14 in 2007. In this second cycle of studies, NAWQA will build its initial assessments of water-quality conditions and will increase its investigation of long-term trends and the factors that affect water quality. Cycle II studies for the MISE study began in 2004.

National Program

| National NAWQA | NAWQA Study Units |