City of Cambridge- Water Audit & Water Loss Study

As part of its ongoing efforts to reduce water losses in the water distribution system, and reduce the levels of Non-Revenue water, the consultant team was hired by the City of Cambridge to perform an International Water Association (IWA) Water Audit and Water Balance for 2016. This audit quantifies water and revenue loss through physical leaks and apparent losses, helping the team to identify steps to minimize and improve system efficiency. The audit results serve as the baseline data to help the City to measure progress over time and aid in establishing a cost effective Infrastructure Leak Index (ILI) target.

The IWA audit identified Revenue and Non-Revenue Water, and quantified each in terms of volumes of water and associated costs. Non-Revenue water is any water purchased from the Region and not sold to customers; and water provided to customers, but under-recorded and billed. The associated costs of Non-Revenue Water included operational costs to purchase water from the Region of Waterloo, and potential revenue loss from under-registering customer meters. A questionnaire was prepared and provided to City and Region staff, in order to guide them through the data gathering process. This process was multi staged, and as information was obtained it was recorded on the questionnaire, and areas where more information was required were identified.

The AWWA Water Loss Control Committee (WLCC) Water Audit Software v 5.0 was used to complete the analysis. The AWWA software is the most widely used by North American water utilities, and is updated by the AWWA Water Loss Control Committee. The data from the series of spreadsheets was entered into the appropriate field in the AWWA software.

The results of the software analysis for the full year of 2016, along with the information gathered about the City of Cambridge’s water system, was used to develop recommendations aimed at reducing the levels of non-revenue water in the City. The recommendations included the replacement of the billing system, replacement of aged customer meters, bulk billing meters, the implementation of DMAs and the yearly completion of a water audit.

The City currently has an active leak detection team seeking out unreported leaks, using noise data loggers, and other equipment. To supplement these efforts, the consultant team developed proposed DMA boundaries to help the City establish more control and understanding of its distribution system.

View/ Download pdf