AWWA ACE59968

The Cornell University Water Filtration Plant (CUWFP) in Ithaca, New York is a 3.6 mgd conventional filtration plant treating a "flashy" creek source. In 2002, the fourth-quarter running annual average (RAA) haloacetic acids (HAA5) concentration was 65 ug/L. This exceeded the Stage 1 Disinfectants/ Disinfection Byproducts (D/DBP) Rule maximum contaminant level (MCL) of 60 ug/L and required disinfection profiling and benchmarking under the Interim Enhanced Surface Water Treatment Rule (IESWTR). This paper discusses alternatives for compliance, including alternate disinfectants and enhanced coagulation. Through the disinfection profiling and benchmarking effort and coordination with the local health department, modifications were made to the existing disinfection practices and a monitoring program implemented to assess the efficacy of the change. The modifications were successful in reducing the RAA HAA5 concentration to below the MCL without impacting the microbiological quality. This paper discusses the challenges of Cornell simultaneously dealing with two interrelated drinking water regulations at the same time. Includes tables, figures.