Mobile DMA testing for leakage assessment: perspectives from Ontario, Canada

Abstract

The formation of discrete regions in a water distribution system, referred to as district metered areas (DMAs), can be a pragmatic approach to diagnose both system and leakage characteristics. Their application, however, has historically been limited in the North American context owing in part to their costly implementation and operational challenges. Both to overcome these barriers and to demonstrate the benefits of DMAs, a leakage testing programme was undertaken in Ontario, Canada. Novelty arises from the development and deployment of a mobile testing unit specifically designed to collect minimum night flow (MNF) and pressure data into temporarily configured DMAs. Moreover, activation of a pressure reducing valve facilitated the direct testing of pressure modulation on leakage reduction. The mobile unit was deployed in 22 DMAs across eight water systems with results indicating a clear relationship between MNFs and system characteristics for well-performing DMAs. MNF benchmarks were quantified to enable an evidence-based assessment of leakage performance at the DMA level in typical Canadian water systems. This project established the proof-of-concept of the mobile unit for providing both accurate and reliable measurements of key leakage performance characteristics and for predicting leakage reduction following system interventions.