AWWA ACE93215

Recent developments in computer software now provide a capability to build representative models which can simulate the propagation and concentration of water quality parameters, such as disinfectants or contaminants, in dynamic flow conditions. Severn Trent Water is developing chlorine concentration models for a number of water distribution system types and establishing standard methodologies for model production and calibration. This paper describes methodology, applications, modeling chlorine decay, chlorine and residual model application. The combination of well calibrated hydraulic models and new computer program facilities provides a capability for producing dynamic water quality models and applying them in practical operational situations. The methodology developed to create a chlorine residual model has been successful.