AWWA IMTECH64734

This slide presentation begins by outlining DBP Stage 2 and outlines information on an initial distribution system evaluation that selected 24 new monitoring sites. The results were used to select 12 compliance monitoring sites. The Austin Water Utility approach used residual mapping which showed: water origination points; water travel through distribution system; lowest residuals were near Thomas Springs; other low residuals were in Avery Ranch; confirmed nitrification problems at Martin Hill and Pilot Knob Reservoirs; unrepresentative water at four TCR sampling locations; used to update routine flushing sites; distance is not always a surrogate for travel time; and, suggests Stage 2 DBP monitoring locations. Further topics outlined include: conventional initial distribution system evaluation (IDSE); near entry point sites; high HAA5 sites; high TTHM sites; and, average sites. Includes tables.