AWWA ACE56283

The Los Angeles Department of Water and Power (LADWP) embarked upon a study to evaluate the feasibility of converting its disinfection practice from free chlorine to chloramine. A field investigation was included in this evaluation, which consisted of a partial conversion of the LADWP distribution system to a chloramine residual. The study realized that the LADWP's large uncovered finished water reservoirs pose the greatest challenge to a chloramine conversion because of difficulties in controlling the chloramine residual in them. The study concluded that the utility would benefit from the conversion; however, large open reservoirs must be replaced or covered in order to maximize the benefits, and mitigate the operating challenges of using chloramine to lower disinfection byproducts (DBPs) in the LADWP distribution system. Includes figures.