06/22/2026
EnviroMix recently presented its Operational Excellence Award to the Boxelder Sanitation District WWTP. Organized in 1965, the Boxelder Sanitation District provides sanitary sewer services to customers near Fort Collins, Co. The district constructed an enhanced biological phosphorus removal (EBPR) wastewater treatment plant in 2014.
In 2021, the Boxelder Sanitation District WWTP was expanded and upgraded to accommodate population growth and stringent new effluent discharge limits on nitrogen and phosphorus. The project encompassed many process improvements, including two new aerobic digesters. Boxelder’s design team selected EnviroMix’s BioCycle-D Optimized Aerobic Digestion Process to provide volatile sludge destruction and stabilization in the new aerobic digesters.
BioCycle-D is designed with a diffused aeration system to satisfy process oxygen demand and a compressed gas mixing system to satisfy mixing requirements. This decoupling of aeration from mixing eliminates over-aeration and facilitates independent control over oxygen delivery and mixing. The system automatically transitions between an aerobic cycle for nitrification and an anoxic cycle for denitrification, alkalinity recovery and energy savings.
“Very shortly after BioCycle-D startup, it was clear that nitrate in the return stream was really low – less than one part – and it didn’t require much effort,” said Craig Hibbard, Manager, Boxelder WWTP. “Having low concentrations of both ammonia and nitrate in our return streams has helped us achieve the lowest total nitrogen discharge levels in the state of Colorado for a couple of years now.”
Additionally, by using the decoupled system, Boxelder reduced energy consumption by 75% versus conventional aerobic digestion estimates. The strength of the BioCycle-D technology, combined with the excellence of the operation staff, ensures the Boxelder Sanitation District WWTP will consistently surpass its goals.
About EnviroMix
Founded in 2009, EnviroMix delivers mixing and process solutions for the water and wastewater industry that drive down energy costs, reduce operator demands and enhance process performance. The company designs and manufactures engineered-to-order, performance-proven technologies that improve water quality and reduce energy consumption for a wide variety of applications in the treatment process. It was acquired by Xylem, a leading global water solutions partner, in July 2025. For more information, visit https://enviro-mix.com.
