AWWA ACE70588

This powerpoint presentation begins by providing a brief overview of the Edwards DWF. Issues include: total organic carbon (TOC) removal required; high disinfection byproducts (DBPs) in the distribution system; and, spring run-off treatment challenges. Regulatory requirements for THMs and HAA5 are presented, along with reasons for roughing filtration. Pilot study objectives included: testing during spring run-off; focus on roughing filtration performance and water quality; test ferric and alum as alternative coagulants; and, test "high rate" HLRs. Jar testing results are provided, along with coagulants, pilot plant schematic, pilot filter media design, color removal in pilot filters, and pilot filter turbidity summary. Summary of findings includes: Ferric - worked well for dissolved organic carbon (DOC) removal, good settled water turbidity, could meet the THM and HAA MCLs; higher filter effluent turbidities than expected; and, alum didn't perform well. Includes tables, figures.