When leaders in the Iowa city of Dubuque began seeking proposals for a wastewater treatment plant upgrade, they made one thing clear.“The RFP clearly stated that the facility must meet the city’s sustainability principles,” says Jonathan Brown, plant manager of what is now called the Dubuque Water & Resource Recovery Center. Those 12 principles, adopted in 2006, guided the planning for a 38-month, $68 million renovation.The project added biogas recovery and improved biosolids handling by converting from fluidized bed incineration to temperature-phase anaerobic digestion. UV disinfection (OZONIA) replaced chlorine. Work on the 1970s-era, 10 mgd plant was completed in May
