AWWA WQTC63998

Compliance with the disinfection byproducts requirements has plagued many water systems since implementation of the Stage 1 Disinfectants/Disinfection Byproducts Rule (D/DBPR) in 2002 (and 2004 for small systems). Many systems struggled to achieve the trihalomethanes (THM's) limit previously set at 100 µg/L, and some found a means to meet the compliance requirements slightly below the maximum contaminant level (MCL) concentration. Extreme challenges are presented to water system operators while attempting to meet more stringent THM requirements. With Stage 2 D/DBPR implementation nearing its deadline, water systems are again being challenged to find extraordinary means to achieve compliance. Imaginative methods of coping with organic precursors and simultaneously achieving compliance with regulatory standards are the focus of this presentation. This paper discusses ongoing research efforts and development of specialized treatment techniques proven to increase organics removal from water in order to reduce disinfection byproducts, especially THM's. Specialized treatment techniques include: fractioning of organics; oxidative conditioning technology; two-stage coagulation; and, enhanced softening. Case studies showing results from optimization of established treatment strategies for THM control also are discussed owing credence to the useful and timely techniques developed by the author. Includes 9 references, table, figures.