The distribution system management program was integral to the success of balancing the disinfection and DBP goals when implementing this major distribution system expansion. The EPANET program could be configured to simulate any distribution system and estimate the chlorine residuals at any point in the distribution system. As no universal mathematical models have been developed to simulate the formation of DBPs in the distribution system, bench studies are critical to estimating the DBP concentrations once a distribution system expansion is implemented. Similar programs, tailored to the needs of a particular expansion, would be integral to the success of any major distribution system expansion. Includes 2 references, tables, figures.