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There is a critical need in the confined livestock industry for development, validation and deployment of alternative waste management technologies that reduce environmental impacts of manure-derived pollutants including nutrients, heavy metals, odors, pathogens, antibiotics, growth hormones, fine particulates, and emissions of greenhouse gases. An advanced energy-efficient tidal-flow constructed wetland technology (TFW), under development since 1993, has demonstrated broad utility for treating high strength wastewater from confined swine and dairy operations. TFW are modular engineered constructed wetland systems that utilize plants(or not), microbial fixed films and innovative fill-and-drain tidal cycling to enhance aerobic and anoxic treatment processes. Repeated fill-and-drain cycling provides efficient passive aeration and facilitates simultaneous nitrification and denitrification. Nitrification occurs when the wetland cells are drained and aerobic, while denitrification and sulfate reduction occur while wetland cells are flooded and anoxic. This energy efficient technology is robust and scalable and can treat from thousands to hundreds of thousands of gallons of wastewater per day. First developed by scientists at the Tennessee Valley Authority (TVA), the technology has been refined by researchers at Living Machine Systems L3C, in Charlottesville VA. (www.livingmachines.com),and California Polytechnic State University (Cal Poly), San Luis Obispo, CA). Pilot-, demonstration- and commercial-scale systems have demonstrated capacities to remove up to 220 kg TKN/ha/day. Research at NCSTATE and Cal Polys dairy research unit has revealed that TFW technology can also significantly reduce odors, metals, and emissions of potent greenhouse gases. This manuscript will provide background information related to environmental risks posed by CAFOs, regulatory issues and research needs, and a review of TFW technology and its application in animal agriculture.