National Topical Studies

NAWQA is addressing five national priority topics that build an understanding of how natural features and human activities affect water quality, and establish links between sources of contaminants, the transport of those contaminants through the hydrologic system, and the potential effects of contaminants on humans and aquatic ecosystems. These topical studies are conducted in those Study Units most affected by these issues; they comprise a set of multi-Study-Unit designs for systematic national assessment. Included are studies on: 

• Effects of Urbanization on Stream Ecosystems (Study design described in Effects of Urbanization on Stream Ecosystems, USGS Fact Sheet 042-02)
  
  
• Transport of contaminants to water supply wells (Study design described in Assessing the Vulnerability of Public-Supply Wells to Contamination from Urban, Agricultural, and Natural Sources, Fact Sheet 2005-3022)
  
  
• Mercury in Stream Ecosystems (Study design described in Mercury in Stream Ecosystems — New Studies Initiated by the U.S. Geological Survey, USGS Fact Sheet 016-03)
  
  
• Effects of Nutrient Enrichment on Stream Ecosystems (Study design described in New Studies Initiated by the U.S. Geological Survey—Effects of Nutrient Enrichment on Stream Ecosystems, USGS Fact Sheet 118-03)
  
  
• Sources, Transport, and Fate of Agricultural Chemicals (Study design described in Studies by the U.S. Geological Survey on Sources, Transport, and Fate of Agricultural Chemicals, USGS Fact Sheet 2004-3098)

  For descriptions of individual agricultural chemical studies: 

  South Fork Iowa River Watershed in central Iowa (USGS Fact Sheet 2005-3064)
  Bogue Phalia Watershed in northwestern Mississippi (USGS Fact Sheet 2005-3050)
  Morgan Creek Watershed in Maryland  (USGS Fact Sheet 080-03)
  Sugar Creek Watershed in Indiana (USGS Fact Sheet 084-03)
  Maple Creek Watershed in eastern Nebraska (USGS Fact Sheet 083-03)
  Granger Drain Subbasin in central Washington (USGS Fact Sheet 082-03)
  Lower Merced River and Mustang Creek Watersheds in California (USGS Fact Sheet 081-03)