AWWA WQTC71343

The Birmingham Water Works Board (BWWB) is taking a proactive approach in anticipating the impending, stricter Stage 2 DBP Rule requirements. The BWWB has implemented over twenty studies involving DBP compliance. This study examines potential DBP formation in finished water storage tanks. The degradation of finished water in storage tanks is of great concern to water utilities. It is widely assumed that tank mixing enhances water quality, and slows the creation of DBPs. The BWWB is conducting a study, which examines the correlation between mixing and water age to DBP production. Ten storage tanks scattered throughout the distribution system, equipped with mixing devices, were sampled for residual chlorine, HAAs, and TTHMs at varying heights. The fact that no tank showed a variation in temperature top to bottom of greater than 1.5 degrees could indicate proper mixing or an equalization of temperature as the sample traveled to the spigot. The second part of this study dealt directly with tank water temperature variations top to bottom as measured by sensors located in a tank. Includes 4 references, table, figure, extended abstract only.