The Greenfield Water Reclamation Plant (GWRP) is one of the largest and newest "end-of-the-line" water reclamation plants in the Phoenix metropolitan area. The sewage treatment plant expansion included a new facility that provided treatment capacity of approximately 16 mgd of liquids and 24 mgd equivalent solids.
The project was awarded the AWPCA's Wastewater Project of the Year and was completed eight days before the scheduled contract completion date. The liquid process included screening, grit removal, primary clarification and biological treatment including nitrogen removal, secondary sedimentation, filtration and disinfection. Solids handling and treatment included blending, thickening, anaerobic digestion and dewatering.
The project also included modification to the City of Mesa's existing Southeast Water Reclamation Plant that added degritting and solids pumping. The project required maintaining in operation, the existing sewage lift station, which was located on the project site and incorporated all components of the existing lift station into the new plant. The existing lift station consisted of an influent pump station, two equalization basins, effluent pump station, odor control facilities and an 11-mile force main. The capacity of the existing lift station was 4.3 MGD.