AWWA ACE63235

This slide presentation outlines a project by Bexar Metropolitan Development Corporation of Bexar County, Texas, to develop a reliable, high quality alternate water resource to Edwards Aquifer. Project background and goals include: using surface water as the source; two stage process including membranes; not impacted by storm events; total organic carbon (TOC) < 2 mg/L and turbidity < 0.1 NTU (95%); highly automated, requiring small staff; guaranteeing 9 MGD; costs less that $1.25 / 1000 Gallons; facility has reduced Edwards Aquifer need by 10,927 acre-feet annually; consistently high quality effluent despite periodic high influent turbidity values; excellent response by plant's monitoring and notification system during and after storm events; and, extremely low number of broken fibers (only 536 out of 5.2 million fibers in 5 years of operations). A qualifying pilot study evaluated three competing membranes, and project fast facts and milestones included: cost of $23 million for construction; 10 year O&M contract; plant capacity 9 MGD per original design; schedule - 16 months (including three month rain delay); and, expanded to 15.5 MGD - March 2005. Specific topics outlined include: plant flow design; raw water structure; UltraPulsator operation and construction; AquaSource membrane filtration; AquaSource ultrafiltration membrane; membrane barrier; disinfection/distribution; plant control guide; plant modifications; project score card; regulatory compliance; and, project costs.