374Water Inc (NASDAQ:SCWO, FRA:8LL) has completed a key factory acceptance test for its AirSCWO system, moving the cleantech company closer to deploying the technology at one of California's largest wastewater treatment facilities.
The North Carolina-based company said the milestone activates the next phase of its partnership with Orange County Sanitation District, which processes more than 180 million gallons of wastewater daily and serves over 2.6 million people across Orange County.
The AirSCWO system uses supercritical water oxidation to destroy biosolids contaminated with PFAS, pharmaceuticals, and microplastics, converting waste into water, benign minerals, and clean energy. The company says the technology achieves a 97% reduction in solids and more than 99.99% destruction of PFAS compounds.
374Water and OC San have planned for system deployment in October, pending permitting and site-readiness approvals.
"This has been a multi-year journey focused on getting the system right,” said Brad Meyers, COO of 374Water. “At every step, we made the deliberate decision-together with OC San-to continue improving the technology so that what we deliver is not just functional, but best-in-class."
OC San General Manager Rob Thompson said the district looks forward to receiving the unit and demonstrating the industrial readiness of supercritical water oxidation for sewage solids destruction.
The deployment comes as wastewater facilities across the US face growing restrictions on biosolids disposal. Maine has banned land application entirely, Florida municipalities are largely limited to landfilling, and some California districts transport biosolids hundreds of miles to neighboring states.
OC San currently ships more than 525 wet tons of Class B biosolids daily to sites in California and Arizona for agricultural reuse and disposal. The company said successful field performance would be a key factor in evaluating broader commercial adoption of the technology.
Completion of the factory test also unlocks the remaining $3 million in contract milestones tied to the OC San project.
The company is targeting a market of roughly 16,000 wastewater treatment facilities across the US.
Shares of 374Water traded 10% higher on the update.