Major water reclamation plant expansion completed in Arizona
The project at Greenfield Water Reclamation Plant represents a 14 million gallon per day (MGD) expansion of liquids and solids treatment that allows the facility to treat up to 30 MGD of liquids and 38 MGD of solids on an annual average flow basis, including through anaerobic digestion.
According to a report by Az Big Media, three municipalities – the city of Mesa and Towns of Gilbert and Queen Creek – jointly own the plant, while the City of Mesa maintains and operates the facility.
Construction for the plant expansion started in November 2017 and was completed despite COVID-19-related restrictions.
Pat Payne, project director for McCarthy which served as construction manager at risk, said: “This plant is the primary means of treating wastewater in the area. As an end-of-the-line plant, it was imperative that plant operations be maintained.
“We very thoroughly vetted and planned all of our outages, and we didn’t have any unplanned outages.”
The liquids treatment processes include preliminary treatment via screening and grit removal, primary sedimentation, biological nutrient removal, secondary clarification, tertiary disk filtration, chlorine contract disinfection, chemical feed systems, and effluent pumping.
Solids handling and treatment include sludge screening, blending, thickening, anaerobic digestion, dewatering, and gas handling.