The community of Marathon has had success bucking the trend to large centralized treatment plants and complex sewer networks. Under orders to improve the quality of its effluent, the community opted out of a $181 million plan for one large treatment facility and connecting sewers, choosing instead to build five smaller decentralized plants, each treating between 200,000 and 400,000 gallons per day, at a total cost of $91 million.
Water quality is a critical issue here. Marathon is a center for diving in the Gulf of Mexico, with Sombrero Reef just a few miles offshore, protected by the Florida Keys National Marine. According to Zully Hemeyer, Marathon utilities director, the wastewater treatment system is critical to protecting the only living coral reef system in the continental US.