Strategy for the development of optimized flushing plans

One aspect to be considered in asset management are the costs for measures to safeguard the drinking water quality in the network. The main reason for visible quality changes is the mobilisation of loose sediments which leads to customer complaints. To avoid brown water the deposits have to be flushed out of the network before a critical level is reached. The distance of time between the flushing procedures depends on the deposit formation process in the pipes. As the velocity of the deposit accumulation is different, in dependence on the material and hydraulic situation, a strategy was developed at DVGW Water Technology Center Karlsruhe (TZW) to determine the sediment-forming processes as a basis for establishing network-specific flushing plans. A. Korth, Sebastian Richardt and Burkhard Wricke in this paper discuss an optimized flushing plan, which offers a minimization of expenditures for the water supplier and an optimization of the cleaning effect. Through this, the water supplier has a clear basis for the calculation of costs for the regular cleaning of the distribution network.