Management of health risks emanating from contaminants in drinking water requires knowledge of the impacts of water quality improvements on household water bills. Factors affecting household water bills vary systemically from place to place. By modeling these factors it is possible to predict impacts from implementing contaminant removal measures. The proposed research focuses on: (1) improvements to a statistical model of water utility costs and prices and residential water usage, and (2) linkage of this model to a data base on contaminant occurrence and contaminant removal costs. Item I is emphasized in Phase 1. The potential commercial application as described by the awardee: Possible application includes use by utilities, utility associations, and state or federal agencies concerned with drinking water quality, costs, usage, and price.