The resuspension potential method: Yarra Valley water's novel approach to routine mains cleaning

Routine cleaning of water mains is frequently employed by water utilities around the world as a means of managing common water quality issues. When employed correctly, water mains cleaning can be effective in removing loosely deposited sediments and bio-films that cause water discolouration, coliform regrowth and unpalatable tastes and odours. Despite its long history in the water industry, water supply practitioners continue to use highly subjective mechanisms to identify when, where and how much to spend on their mains cleaning programs. This paper discusses the benefits of using the Resuspension Potential Method, an objective means of planning and implementing mains cleaning, to achieve an optimum outcome for both the water company and its customers. Since 2005, Yarra Valley Water has undertaken Resuspension Potential Method measurements in 13 of its water quality zones to gain a better understanding of sediment accumulation rate in the zones over time. Ultimately the information will be used for more effective planning and proactive implementation of the mains cleaning programme.