Southeast Regional Water Treatment Plant Major Upgrades Design and Construction Services

The Seminole County Environmental Services Department (SCESD) owns and operates the Southeast Regional Water Treatment Plant (SER WTP), which is the primary source of potable water serving its service area. The ground water source for the plant had elevated concentrations of hydrogen sulfide and organics. The existing treatment at SER WTP did not target these parameters, resulting in disinfection byproduct levels above the new Stage 2 Disinfectant/Disinfection Byproduct Rule (D/DBP) regulations.

To meet the Stage 2 D/DBP Rule and county goals for sulfide removal and disinfection byproducts (DBP) formation, major upgrades to the SER WTP were required. Following pilot studies performed by CHA, the county selected the addition of ozonation treatment to oxidize the sulfide followed by granular activated carbon (GAC) treatment to reduce organics.

The SER WTP was the first WTP in Florida to use ozonation and GAC treatment to meet Stage 2 D/DBP requirements. CHA designed the major upgrades, including the core components of ozone and GAC treatment, conversion from chlorine gas to sodium hypochlorite for disinfection, control system upgrades, and new electrical service with increased reliability. Final design and permitting services included obtaining multiple permits through FDEP, including an extension on the timing for Stage 2 compliance, Seminole County Planning and Zoning Development Review Committee and Building Department.

CHA performed construction phase services and coordinated with SCESD and the contractor. Since this facility is the primary WTP for the service area, the construction was sequenced such that the plant could remain in operation. CHA served as the Engineer of Record for the construction phase, including hands-on startup and certification services for the county.

Project Services:
  • 19.4 MGD Water Treatment Plant
  • Ozone Treatment
  • GAC Treatment
  • Stage 2 D/DBP Compliance
  • Planning
  • Design
  • CMAR Delivery Method