NEWCASTLE LAGOON Wastewater Treatment Plant, Newcastle, Wyoming

NEWCASTLE LAGOON is a municipal wastewater treatment facility located in Newcastle, Weston County, Wyoming, United States. It serves a population of about 3,532 residents, typical of a small community in the rural western U.S. The plant is situated along WY 450 and operates under the regulatory framework of the U.S. Clean Water Act, which requires National Pollutant Discharge Elimination System (NPDES) permits for all point source discharges. As a small agglomeration, the facility likely employs lagoon-based treatment, a common and cost-effective method for small communities in the region. Lagoons use natural biological processes to treat wastewater, often achieving secondary treatment levels. Such systems are typically designed to handle the organic load from the local population. The treated effluent is discharged into nearby surface waters that drain into the Cheyenne River, a tributary of the Missouri River system. This ultimately flows to the Mississippi River and the Gulf of Mexico. The plant plays a key role in protecting local water quality and downstream ecosystems, including the Missouri River's diverse aquatic habitats.

The plant discharges into local streams that feed the Cheyenne River, part of the Missouri River basin. This watershed supports a variety of aquatic life, including fish species such as channel catfish and walleye. The Missouri River system is ecologically significant, providing habitat for migratory birds and other wildlife. Proper wastewater treatment helps maintain water quality in this semi-arid region, where water resources are limited.