Using limited data to assess future needs

Most major urban utilities are aware of the heed to keep records of distrib ution System water mains. These records-which typically include data about water main break history, pipe material, pipe vintage, and soil type-are ev entually 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 war ranted. Presented is a case study that followed five essential steps: (1) b undle data on water main breaks into homogeneous groups to predict future b reaks for water utility regions for which data were insufficient, (2) estab lish breakage rate:patterns for these groups to project future breakage rat es, (3) use projected breakage rates to determine the economic life of wate r mama, (4) examine probabilistic scenarios of water main life, and (5) det ermine the investments required to replace water mains.