R. Brian Culpepper

Abstract

The Safe Drinking Water Act Amendments of 1996 require a source water assessment program (SWAP) for all public drinking-water supplies. Source water may be defined as the water taken from rivers, reservoirs, wells or springs for use as public drinking water. The assessment determines the potential susceptibility to contamination of drinking-water supplies.

A source water assessment is intended to provide a basis for developing, implementing, and improving a source water protection program. These programs require administrative agencies or individuals to delineate protection areas for water intakes, inventory significant contaminants within the protection areas, and determine the susceptibility of the water supply, based upon the conditions found within the protection area(s). These assessments are often used to focus environmental or public health programs developed by local governments, and concerned citizens.

In 1998, the Arkansas Department of Health (ADH) embarked on developing the source water assessment for Arkansas' Public Water Supplies. They were responsible for identifying the appropriate assessment methodologies for the Public Water System (PWS) Intakes within Arkansas and CAST was hired to provide assistance with the Geographic Information System (GIS) analysis required during the initial two years of the project. This project marks the first time a statewide assessment of the source water resources and their susceptibility to potential contamination has ever been completed. It would not have been possible within the fiscal and time constraints without the use of GIS technologies. This report was written to summarize our GIS methodologies for the project and to serve as a resource for future GIS implementations within the Arkansas Department of Health - Engineering Section.

The ADH and the United States Geological Survey (USGS) Office in Little Rock have coordinated the Arkansas Source Water Assessment but have also received assistance from the Arkansas Water Resources Research Center, and the Department of Geosciences at the University of Arkansas Fayetteville, Arkansas.