Ease of Operation
This goal included the evaluation and selection of equipment, as well as the application and orientation to provide good ergonomics of the movements of the operators, reduce maintenance and replacement frequency, and simplify the controls and operations of the WRWRF.
This approach started with a design to lift the influent wastewater through the headworks and into the reactor, where a gravity flow could be introduced. This complemented the selection of the membrane bioreactor (MBR) technology, where pumps must be used to create a vacuum to draw permeate out of the reactor. The permeate then gravity-flows through the deactivation process prior to the effluent lift station. This provided the benefit of being able to drain the entire reactor, preventing the need to raise and lower pumps to remove wastewater for maintenance in the future.
“Our largest obstacle was not having minimum flow required at the time of commissioning. This ended up taking an additional 12 months to gain a minimum flow of 10,000 [gal per day (gpd)] to fully commission the WRWRF. The designer and owner developed a plan to commission the WRWRF with clean water once construction was complete, to enable the start of warranties and to demobilize the contractor and save budget,” Tack said. “During the next 12 months, GHD operated the facility a few days a week to monitor and ensure the mechanical systems maintained functionality and to ensure the facility was ready for dirty water commissioning once the minimum flows were established. At the time of full commissioning, GHD and the owner were able to commission the facility within 30 days and successfully train the town staff and begin regulatory reporting.”
Minimize Expansion Costs & Service Interruptions
The WRWRF has an average day capacity of 100,000 gpd and a peak day capacity of 300,000 gpd in Phase 1, which is planned to be expanded in Phase 2 to the average day capacity of 365,000 gpd, utilizing the same footprint with only minor equipment additions. This foresight was an innovation implemented to maximize the life cycle and minimize the long-term operational and maintenance costs.
The techniques implemented on the project provide for the extended life cycle of this facility by promoting the use of high-quality base infrastructure with innovative technologies to enhance and sustain the high quality of the effluent. The decisions made by the team during the planning and design were well executed by the contractor and serve the town’s operational and maintenance team to this day.
“The project exceeded our expectations and addressed all stakeholder concerns while providing a technically excellent design, on time, and on budget” said Matt Egan, town of Wickenburg operations manager, water/wastewater/electric.
Project Year: 2018-12-01
Contractor: Currier Construction
Designers: GHD Inc.
Owner: Town of Wickenburg
Location: Wickenburg, Ariz.
Cost: $6,583,504
Size: 208 gpm