ENHANCED COAGULATION - A PRELIMINARY EVALUATION

Researchers conducted preliminary enhanced coagulation tests at the Me tropolitan Water District of Southern California's (MWDSC's) 5.5-mgd d emonstration plant from August to October 1999. California State Proje ct water and Colorado River water were tested. The first goal was to d etermine whether this mode of operation is an effective strategy for c ontrolling disinfection by-products (DBPs) and DBP precursors at MWDSC facilities. If this strategy proved to be successful, the second obje ctive was to estimate the additional operational costs of complying wi th the proposed Disinfectants/DBP Rule and to identify the coagulation conditions that minimize these costs. Although the results show that enhance coagulation can meet the criteria being considered for the rul e, this process will increase MWDSC's cost of treatment.