Okaloosa, FL
In 2005, Okaloosa County Water and Sewer Department (OCWS) selected Ardurra (formerly Constantine Engineering) as their Program Manager to construct the 10 mgd Arbennie Pritchett Water Reclamation Facility (APWRF) using a progressive design-build process. Using this approach, the County realized substantial benefits for its customers, including timely and efficient scheduling, optimal risk allocation, competitive design selection and innovation, clear assignment of performance responsibilities to a single contracting entity, and long term WWTP reliability and life-cycle cost savings.
Ardurra managed the $65 million program that included the design and construction management of the 25 mgd re-pumping station to convey flow from the existing Garniers WWTP site to the APWRF site, a 200-acre rapid infiltration basin (RIB) effluent disposal system, construction of more than 10 miles of new 8-inch to 36-inch diameter raw sewage and effluent piping, and decommissioning and demolition of the Garniers WWTP. Ardurra managed the overall permitting effort for the program, performed the conceptual design for the project, and managed the design-build process. Ardurra also provided administration, design, and construction services.
Ardurra, working with OCWS, developed a conceptual plan for the new WRF process that included a new 10 mgd facility that would be easily expandable to 15 mgd. The new facility included a headworks with two 25 mgd perforated plate screens, a 37.5 mgd manual bypass screen, two 25 mgd vortex grit removal units, grit pumps and disposal systems. A new biofilter odor control system is provided to evacuate convey odors from the headworks to a wood-chip biofilter for treatment.
The initial WRF included two 5 mgd, 4-stage Bardenpho Ovivo oxidation ditch treatment units, two 125-foot diameter secondary clarifiers, and an ultraviolet irradiation disinfection system. Treated effluent flows by gravity to the effluent pump station and is pumped to one or two of the 18 RIBs or to a public access reuse filtration and chlorine disinfection system. Plant reuse pumps are available to convey treated effluent within the WRF. A single rotary drum thickener thickens the WAS prior to discharging it by gravity to the two aerobic digesters. The digested sludge is pumped to a single centrifuge for dewatering and discharge into the 40-ton trucks.
In 2019, the OCWS Arbennie Pritchett WRF Expansion was awarded the Design Build Institute of America Florida Region Honor Award in the Water/Wastewater category.