AWWA IMTECH51379

Computers are widely used by water utilities to model the hydraulic behavior of their water distribution networks. Over the last five years, a number of network modeling packages have been produced with a facility for modeling chlorine decay. However, modeling chlorine is somewhat more complex than modeling the hydraulics within a network because it involves additional complex chemical and biological interactions. Hence there can be considerable difficulties in producing accurate and durable chlorine models. This paper presents an overview of a study undertaken to develop a cost-effective methodology for producing models of free chlorine with adequate predictive accuracy and satisfactory durability for both design and operational applications. The work was based on distribution networks in the United Kingdom operated by Severn Trent Water Limited. All measurements and conclusions in this paper relate to free chlorine. The paper addresses three issues: the mechanisms by which chlorine decays and the implications for chlorine network models; the accuracy, sensitivity and durability of chlorine network models; and potential applications for chlorine models and proposals for methods by which models can be maintained in a state suitable for their intended application. Includes 8 references. See more