Since trihalomethane studies began in Carbondale, Illinois, almost two decades ago, the city's water utility has experienced only limited success in the long-term control of these compounds. For the past three years, however, tower aeration has proven to be most effective in this regard. Aeration has been demonstrated to be an easy, efficient means of controlling total trihalomethanes, particularly chloroform, which have been identified as possible carcinogens. This method is also less expensive than most chemical treatments for the reduction of the natural organic materials found in surface waters that react with disinfectants to form disinfection byproducts. This paper discusses the history of trihalomethane control in Carbondale and the success of the aeration process to date.