About an hour south of Atlanta, the city of Barnesville, Georgia is a town of shady, tree-lined streets, a fondness for celebrating its history, and a sharp eye on the future. In 2013, as its 30-year-old wastewater treatment plant was reaching the end of its useful life, Barnesville found itself planning for a future of growth, progress, and a new, state-mandated <0.6 mg/L total phosphorus (TP) wastewater discharge limit.