F148.pdf (253.87 kB)
CCWI2017: F148 'Rusby Wood a Smart Network for Sustainable Discolouration Risk Reduction'
journal contributionposted on 2017-09-01, 15:24 authored by Dominic Cook, Stewart Husband
Managing discolouration customer contacts has never been more important to UK Water Companies, with the Economic Regulator setting strict water quality customer contact targets, imposing large financial penalties if they are exceeded without providing additional funding to facilitate necessary network investment. 19% of discolouration customer contacts can be directly associated with the mobilisation of discolouration material from the trunk main distribution system, but these pipes due to their criticality of supply and size are extremely expensive to clean. This paper presents a practical example demonstrating that with the addition of relatively inexpensive automated flow control, metering and instrumentation, a water supply system can be configured to automatically re condition itself. Five trunk main sections will sequentially run a maximum flow between service reservoirs before returning to normal operating flows. This produces a safety headroom between normal operating flow and the maximum hydraulically available flow this dramatically reduces discolouration risk should an un planned high flow event occur on the network. The system is designed to ‘self check’ whereby sending and receiving reservoir levels and flow pressure and turbidity at strategic points are within set parameters before the reconditioning occurs. In addition, if abnormal flows, pressures or turbidity levels are detected at any time on one of the trunk main sections, the inlet valve on the appropriate receiving reservoir will automatically close. This prevents discoloured water from entering the reservoir allowing the operator time to repair and flush the affected main.