AWWA ACE93171

Potentially more stringent regulations for total trihalomethanes (TTHMs) and other disinfection byproducts are possible in the future. Utilities are being forced to find a balance between minimizing the formation of disinfection byproducts while at the same time providing protection against microbial contamination. When quality and quantity demands conflict, and a utility may have to use sources of marginal quality, which makes achieving water quality goals even more difficult. This paper describes the efforts of the Drinking Water Research Division (DWRD) of the USEPA, the North Marin Water District (NMWD) and Montgomery Watson Inc. (MW) to develop a water quality model. The model is based on EPANET, the US EPA's water quality monitoring and simulation software. The model answered questions about what methods of treatment would allow the utility to comply with both disinfection byproduct and microbial regulations.