AWWA ACE58113

Water utility operators have long known that throttling down system pressure reduces total consumption, and this strategy is sometimes used to deal with short-term supply shortages. Water pressure can vary considerably across households if each dwelling is not fitted with its own pressure-regulating valve, especially in areas of varying elevation. And this uneven pressure affects domestic irrigation the most, because the irrigation offshoot is often taken before the pressure-regulating valve, if such a valve is present at all. Therefore, there is good reason to believe that reducing pressure will save water. For this reason, system pressure optimization is included as a Potential Best Management Practice (PBMP) in the Memorandum of Understanding Regarding Urban Water Conservation in California (MOU). But, utility-operations staff normally harbor concerns about the impact of pressure reductions on pressure-related customer complaints, although the sensitivity of customer complaints to system pressure has never been systematically studied. This study examines how effective this PBMP is likely to be in practice in terms of both water savings and increased customer complaints. One potential benefit that was not evaluated in this study, however, is the impact of reduced pressure on lowering water lost to leakage, which may be significant in older cities with a high percentage of unaccounted for water. Includes reference.