Rehabilitation strategies for water distribution networks: a literature review with a UK perspective

Abstract Primarily, a rehabilitation strategy should aim to satisfy the regulatory requirements set down in respect of water distribution network operation. However, water companies in the UK have come to recognise that the business needs associated with the improvement of the deteriorating fabric of their distribution networks extend beyond these requirements. Extra economy can be gained by operating the networks efficiently based on a rehabilitation strategy which considers the associated costs over an extended period. Economic, hydraulic, reliability and water quality performance criteria must be optimised as part of an effective strategy. Numerous rehabilitation decision making approaches have been presented. However, many have adopted flawed economic approaches and have been based inadequately on one or two selected performance criteria. Few models have considered the extended planning horizons associated with a whole-life costing approach to this problem. However, the multi-objective optimisation approaches which have been developed recently have the potential to be developed into the required whole-life costing model based on the appropriate economic model and performance criteria.