A full-scale regional reactivation project was conducted by the Manchester Water Works in New Hampshire in conjunction with the Connecticut Water Company, and the Danvers, Massachusetts and Lowell, Massachusetts, water utilities. Each of the utilities provided approximately 40,000 lb (18,160 kg) of carbon to be transported to Manchester for fluidized bed reactivation. Project results indicate that on-site reactivation at Manchester was considerably cheaper than replacing spent carbon with virgin carbon. Regional reactivation proved to be cheaper for the utilities than either replacement or estimated on-site reactivation, even when the costs of transportation were taken into consideration. The effects of economy of scale were demonstrated by the project, with the small utilities benefiting from participation in a regional system. Includes 4 references, tables.