The Miami Valley River Index is an understandable and scientifically-based measure of thewater quality of the rivers in the Dayton, Ohio, metropolitan area. The primary product ofthe 2-year (January 1999 to December 2000) EMPACT pilot project is the development anddistribution of a multi-media "River Index" that provides understandable information to thegeneral public regarding overall river water quality, flow stage, and water clarity.The River Index uses a network of six real-time monitoring stations combined with periodicmanually collected samples that describe aspects of water quality. Once collected, the dataare averaged, categorized, weighted, and summed according to a site-specific calculation foreach station. The output of the calculation is a rating ranging from excellent to poor thatgives an estimation of the water quality. The rating is transmitted to the public through theInternet (www.riverindex.org), a daily newspaper, and television.Specific project goals, technical approaches, data, costs, and preliminary conclusionsfollowing the first field season of operation are presented and discussed in this paper.Although the primary objective of the project focused on providing information to heightenthe public's awareness of the Miami Valley area rivers, technical aspects and lessons learnedcould help similar projects involving real-time data collection and reporting. Includes tables, figures.