Tampa is gearing up to build what city officials say will be the largest Suspended Ion Exchange (SIX) water treatment plant on the planet at the David L. Tippin facility, a move Mayor Jane Castor says will cut chemical use, help knock down "forever chemicals" in tap water and save taxpayers around $2 million a year.
What the city approved
According to a Carollo Engineers press release, Tampa City Council has signed off on funding to design a full-scale SIX installation at the David L. Tippin Water Treatment Facility. The system is being sized to handle up to 140 million gallons of water per day, which would make it the largest SIX deployment in the world, and the city plans to deliver the project through a design-build approach with industry partners.
Pilot findings and what they mean
A ten-month pilot run tested SIX as a pre-treatment step alongside the plant’s existing coagulation, ozone and biofiltration processes. The city’s pilot report found significant reductions in organic matter and much longer filter runs, which boosted overall treatment performance. Those improvements reduced the organic fouling that can interfere with downstream PFAS removal technologies, according to the report.
Costs, timing and savings estimates
Industry coverage puts the total project cost near $200 million and notes that construction could start in the late 2020s as the plant adds capacity, according to Engineering News-Record. Based on pilot modeling, Carollo Engineers and city materials point to major reductions in chemical use and operating costs. The firm projects roughly $1.7 to $1.9 million in annual savings, a figure Mayor Castor rounded to about $2 million in her X thread announcing the plan.
Why this matters for residents
The project lands as the U.S. EPA has finalized national drinking water limits for several PFAS chemicals, setting compliance deadlines for public water systems across the country, according to the EPA. Local reporting previously found that Tampa detected slightly elevated PFOA and PFOS levels in finished water, measurements that put the utility close to those new federal thresholds, as reported by WUSF.
What's next
For now, the focus is on design, permitting and procurement. The city has posted RFQs and information packages for upgrades at the Tippin plant as it folds SIX into a larger slate of capital work. The City of Tampa RFQ packet lays out the master planning and condition assessments that will shape how the new system is rolled out. City officials say the SIX installation is one part of a broader effort to replace aging pipes, modernize treatment and keep long-term operating costs in check.
