AWWA WQTC65839

This powerpoint presentation begins by providing a brief overview of the city of Ottawa, Ontario, Canada, and its problem with corrosion control. The regulatory context is introduced, and the objectives of a performance review study are listed. The focus is on the objectives of corrosion control and water stability that include: manage corrosion control byproducts (iron, lead, and copper); improve water stability by managing pH in water discharged to the system within approximately 2 pH units, and by managing pH stability across the distribution system; and, other water quality benefits expected such as improvements in residual maintenance, bacti performance, colored water events, and managing aluminum in treated water. Topics covered include: Establishing the Treatment Objectives; Establishing the Treatment Chemicals; results of Lead (Flushed Sample, variable pH), Elevated Lead Levels Sept 2002, Lead Levels and Temperature, flushed, random LSL homes. The results of other water quality benefits are presented, along with assessment of future compliance, and the cost of managing risk of future non-compliance. Includes figures.