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By Matthew Early T he WaterHub at Emory University is a decentralized, on-site urban water reclamation and reuse facility that implements a holistic approach to modern water management. Through innovative technologies, the ecologically engineered reclamation facility treats up to 400,000 gallons daily, recycling up to two-thirds of the university's wastewater production, while reducing the campus water footprint by nearly 40 percent. By localizing water supply through on-site reuse, Emory University has greater control over supply, water quality, and campus resiliency. Nestled among the trees and green spaces of Emory's campus resides a wastewater reclamation and reuse system that is changing the paradigm of commercial-scale water management. A Quarter Century Of Water Stressors Throughout history, water has remained the single thread that has brought us all together. From the aqueducts of the Romans to advances in agricultural irrigation, water remains a vital resource for every community. Recently, though, our newspapers have been topped with headlines of water-related challenges in almost every corner of the globe. No stranger to its own water-related challenges, Emory University sought to reduce its dependence on municipal water and de-risk the campus from future water challenges. Located only 15 minutes from downtown Atlanta, Emory University lies within one of the smallest watersheds serving a metropolitan area of its size. Water is becoming increasingly limited, with scarcity exacerbated by revolving drought conditions and political stressors over water rights. In a 25-year dispute known as the "Tri-State Water Wars," Georgia, Florida, and Alabama have been vying for the allocation rights of water withdrawals from the Chattahoochee River Basin, which serves the Atlanta metro area. Further compounding these challenges were the U.S. EPA's issuance of consent decrees against the City of Atlanta (and the surrounding counties) to improve water and wastewater management and resolve issues related to combined sewer overflows (CSOs). Due to these new federal mandates, water and wastewater utility costs skyrocketed between 2007 and 2012 and are now considered some of the highest rates in the country. Consequently, sustainable water management has become a critical challenge for the region and a specific operational focus for large water consumers in the metro Atlanta area. Emory University has a significant water footprint, using close to 350 million gallons of water annually with over 50 percent of campus water use considered non-potable demand. The university has five major chiller plants and one steam plant that provide critical heating and air conditioning services to the campus. Together, these six utility plants consume 30 percent of the total campus water supply, or approximately 105 million gallons annually. From these challenges, Emory began to deploy water conservation campaigns beginning around 2005, successfully implementing rainwater collection and storage, installation of low-flow fixtures, urinals, and shower-heads, and capturing graywater for reuse in toilet flushing. The university had significantly decreased total potable water use, but the magnitude of the stresses and challenges dictated a more strategic and impactful water management solution. Subsequently, Emory University found itself in a unique position to develop a water management strategy centered on wastewater reclamation and reuse. Ecological Design For Strategic Water Management The WaterHub is an adaptive, ecological water reclamation system designed to treat domestic sanitary sewage, mined directly out of the campus sewer system, and reclaim it for non-potable demands including heating, cooling, and toilet flushing. Commissioned in the spring of 2015, the WaterHub at Emory University is an eco-engineered treatment plant composed of innovative and proven biological treatment principles. The 4,400-linear-foot distribution system seamlessly integrates into the campus framework while providing recycled water to the university's three largest chiller plants, the campus steam plant, and toilet flushing in residence halls. Designed to accommodate future expansion and increased non-potable demands, the WaterHub is expected to save 70 million gallons during its first year of operation, with future uses also including irrigation at major athletic fields. The system allows flexible site integration, a compact footprint, and a natural aesthetic conducive to a dense urban setting. The WaterHub is divided into two locations: the upper site and lower site. At the upper site, performance landscaping allowed previously undevelopable space to become home to a 3,200-square-foot greenhouse, or "glasshouse," containing a hydroponic treatment system. Considered the heart of the 12 wateronline.com n Water Innovations Inside An Innovative Urban Water Reclamation Facility The award-winning WaterHub at Emory University is more than a mere campus treasure — it has become a model of sustainable wastewater treatment for urban water management of the future.