Tampa SIX water treatment system plans have taken a major step forward after Tampa City Council approved funding for the design of a large-scale Suspended Ion Exchange (SIX®) installation at the David L. Tippin Water Treatment Facility.
Once completed, the system will be the largest SIX® installation in the world and the first full-scale deployment of the technology in the United States. The facility is designed to treat up to 140 million gallons per day, significantly enhancing drinking water quality for the region.
The project is being delivered by the City of Tampa Water Department in partnership with a design-build team led by Garney and Wharton-Smith, with Carollo Engineers serving as lead designer.
Tampa SIX water treatment system to transform organics removal
The Tampa SIX water treatment system is based on Suspended Ion Exchange technology, developed by PWNT, part of Nijhuis Saur Industries. The process is designed to remove dissolved organic matter from surface water more efficiently than traditional coagulation methods.
The David L. Tippin Water Treatment Facility currently treats water sourced from the Hillsborough River, where seasonal fluctuations can lead to elevated levels of total organic carbon (TOC). High TOC levels increase the risk of disinfection byproduct formation and require more intensive chemical treatment.
SIX® technology addresses this challenge by improving organics removal upstream, helping to stabilise treatment performance and reduce reliance on chemicals.
Pilot results show cost and efficiency gains
The decision to proceed follows a 10-month pilot study that evaluated the performance of the SIX® process across the full treatment train, including coagulation, sedimentation, ozone treatment and biofiltration.
Results showed a significant improvement in finished water quality, alongside a reduction in chemical usage of up to 79%. The system is also expected to deliver annual cost savings of between $1.7 million and $1.9 million, with findings independently validated.
Filter efficiency was also reported to have doubled during testing, further supporting operational performance improvements.
Supporting PFAS treatment and future regulation
Beyond immediate benefits, the Tampa SIX water treatment system is expected to support compliance with emerging contaminant regulations, including PFAS. By removing organic matter that can interfere with downstream processes, SIX® improves the effectiveness of technologies such as granular activated carbon.
The process also provides some direct removal of PFOS, contributing to overall contaminant reduction.
Rory Jones, Director of the Tampa Water Department, said the decision reflects a long-term commitment to improving water quality and operational resilience.
Vinnie Hart of Carollo Engineers described the project as a significant advancement that could set new standards for utilities dealing with high-organic source waters.
Setting a benchmark for US water utilities
Once operational, the facility will serve as a reference site for SIX® technology in the United States, providing performance data and operational insights for other utilities considering similar upgrades.
The project reflects a wider industry shift towards advanced treatment technologies capable of addressing both traditional water quality challenges and emerging contaminants.
For more on advanced treatment technologies, visit our Water Treatment section.
