National Water-Quality Assessment (NAWQA) Project
Birmingham information sheet (2 pg PDF, 3.12 Mb)
This information sheet highlights selected findings of a comprehensive assessment by the National Water-Quality Assessment Program of the U.S. Geological Survey of the effects of urban development on stream ecosystems in nine metropolitan study areas. These are a few of the findings from the study in the Birmingham Metropolitan Area.
Prepared for November 30, 2012 Congressional briefing
Thirty sites were selected with drainage basin areas between about 2 to 26 square miles (5 to 66 square kilometers) and had minimal natural variability among them. The land use gradient went primarily from cropland and pasture to urban. Sites represented a broad range of urban intensity from low to high.
Landcover, urban intensity, and site locations
Time of study:
Site selection in 1999.
Data collection from spring 2000 to summer 2001.
The Birmingham study area is in Georgia and Alabama in the southeastern USA. Major metropolitan areas include the Birmingham, Anniston, and Gadsden, Alabama. The population in the Birmingham Metropolitan Area increased 9.6% from 1990 to 2000 and was about 920,000 people in 2000 (U.S. Census Bureau, 2000).
The study area is in the Ridge and Valley ecoregion (Omernik 1987), where mountain ridges are typically sandstone, valley floors are primarily limestone or shale (Johnson and others, 2002), and elevation ranges from about 358 to 1,995 feet (109 to 608 meters) above sea level (U.S.Geological Survey, 2005).
The dominant natural vegetative cover is Appalachian oak forest, and land use is predominantly cropland and pasture, and urban lands (Johnson et al. 2002).
The climate is warm and humid with mean annual temperature of 61 degrees Fahrenheit (16 degrees Celsius) and mean annual rainfall of 56.5 inches (144 centimeters)(Daymet, 2005). Most of the precipitation is evenly distributed throughout the year, except for a dry period in August to October.
Highest streamflows occur in February, and lowest streamflows occur in June to September (Johnson and others, 2002); however, streamflows during 1999-2001 were below the long-term (>50 years) average due to drought conditions in the region (Atkins and others, 2004). Streams in this region support warm-water biological communities.
For more information about the study area — http://al.water.usgs.gov/nawqa/mobl/