AWWA JAW49860

Most major urban utilities are aware of the need to keep records of distribution system water mains. These records--which typically include data about water main break history, pipe material, pipe vintage, and soil type--are eventually used to allocate budgets to replace, rehabilitate, or repair aging distribution systems. Many utilities have incomplete or scarce water main data, which may make financial planning difficult. Thus, a methodology that facilitates the use of scarce, available data to assess future needs is warranted. Presented is a case study that followed five essential steps: bundle data on water main breaks into homogeneous groups to predict future breaks for water utility regions for which data were insufficient; establish breakage rate patterns for these groups to project future breakage rates; use projected breakage rates to determine the economic life of water mains; examine probabilistic scenarios of water main life; and, determine the investments required to replace water mains. Includes 31 references, tables, figures.