Lower Illinois River Basin Water-Quality Assessment
Mitchell A. Harris, Kelly L.Warner, and George E.Groschen
Intensive data collection for the U.S. Geological Survey
National Water-Quality Assessment study of the Lower Illinois River Basin
begins in October 1995. The study area extends downstream from Ottawa and
includes 17,960 square miles of central and western Illinois. The study
design addresses water-quality issues on national, regional, and local
scales. A network of basic fixed sites is established so the sites represent
combinations of important large-scale natural and anthropogenic factors.
Additional sites will be located to examine basin- and sub-basin water
quality conditions. The ground-water component of the study assesses water
quality of major aquifers and shallow ground water, and uses flow-path
and river-reach studies to characterize local ground water interactions.
Bed sediments and biological tissues are analyzed for trace elements and
hydrophobic organic contaminants. Ecological studies evaluate the effects
of physical and chemical characteristics of water and hydrologic conditions
on aquatic biota. Water-column studies evaluate physical and chemical characteristics
and relate these to the hydrologic setting.
U.S. Geological Survey
221 N. Broadway
Urbana, IL 61801
(217) 344-0037
maharris@usgs.gov, klwarner@usgs.gov,
gegrosch@usgs.gov