Notice Regarding Discharge to the Sanitary Sewer System
Published on June 26, 2026
For Immediate Release
Friday, June 26, 2026
Notice Regarding Discharge to the Sanitary Sewer System
CHEYENNE, WY – The City of Cheyenne Board of Public Utilities (BOPU) is reminding all residential, commercial, and industrial customers that the discharge of hazardous substances into the sanitary sewer system is strictly prohibited. Violations may result in fines, penalties, liability for damages, and potential disconnection from water and sewer services.
Over the past two decades, BOPU's Wastewater Reclamation (WR) facilities have encountered a variety of hazardous materials discharged into the sewer system, including gasoline, petroleum products, excessive grease, and concrete. In one instance, a substance discharged by an industrial user triggered alarms indicating the potential presence of explosive materials. These incidents can damage critical wastewater infrastructure, disrupt treatment processes, and create dangerous working conditions for employees responsible for treating the city's wastewater.
Recognizing these risks, BOPU established its Industrial Pretreatment Program (IPP) in the early 1990s. The program protects the sanitary sewer system through the development and enforcement of local ordinances, permitting industrial users, routine inspections and sampling, compliance monitoring, and enforcement actions when necessary. The program also helps ensure compliance with applicable state and federal regulations.
Recently, BOPU experienced operational disruptions resulting from the discharge of a biological contaminant by an industrial user.
In late February 2026, BOPU laboratory staff identified an unusual bacterium during routine wastewater sampling. Additional testing conducted by the Wyoming Public Health Laboratory identified the organism as Cupriavidus gilardii. Subsequent research determined that this bacterium is naturally occurring and is commonly found in soil and groundwater environments.
Cupriavidus gilardii is known for its high resistance to metals and has been associated with certain industrial applications involving metal reduction processes, including some advanced manufacturing and industrial systems. Research also indicates that, while infections are extremely rare, the bacterium may pose health risks to immunocompromised individuals and the elderly through direct exposure. To date, only a limited number of documented human infections have been reported worldwide.
Because Cupriavidus gilardii is not a regulated contaminant, BOPU immediately notified the Wyoming Department of Environmental Quality (DEQ) upon confirming its presence. At the time of notification, no known source had been identified.
Through extensive field investigations and targeted sampling, BOPU staff ultimately traced the source to an industrial user within the system. The industrial user's discharge privileges were immediately and permanently terminated.
Although the unauthorized discharge ceased, the bacterium had already established itself within the biological treatment processes at both BOPU's Wastewater Reclamation facilities. As a precautionary measure, the City's reuse water system was taken offline shortly after seasonal startup operations began.
Over the past two months, BOPU staff have undertaken significant remediation efforts, including draining and disinfecting the entire reuse water system and Prairie View Pond to eliminate any remaining bacterial presence. To prevent potential migration throughout the reuse distribution network, all affected irrigation systems were temporarily converted to potable water supplies.
Recently, the BOPU has detected only minimal residual traces of the bacterium within its treatment facilities. Laboratory staff have and will continue extensive monitoring and sampling efforts. Following consultation with the Laramie County Public Health Department, the BOPU has determined reuse water irrigation services will resume on Monday, June 29, 2026. Signage will be posted in areas where reuse is utilized.
Since its establishment in 1943, the Board of Public Utilities has been responsible for managing and operating the city's water and wastewater systems. For more than 80 years, BOPU has remained committed to providing safe, reliable, and sustainable utility services to Cheyenne residents and businesses, and that commitment remains unchanged.
BOPU encourages all customers to be mindful of what enters the sanitary sewer system. Fats, oils, grease, wipes, including products marketed as "flushable", industrial contaminates such as gasoline, petroleum products, and other inappropriate materials should never be disposed of through drains or toilets. These substances can cause blockages, damage public and private infrastructure, and lead to costly repairs.
Commercial and industrial customers are also encouraged to ensure that all chemicals, processed waters, and other potentially harmful substances are disposed of properly and in accordance with applicable regulations to help protect the City's wastewater infrastructure and treatment processes.
For more information regarding prohibited discharge to the city’s wastewater system, please reference Cheyenne City Codes 13.20.050-070. Further inquiries can be directed to BOPU's IPP staff at 307-635-3163 or ipp@cheyennebopu.org.
Contact:
Erin Lamb, Administrative & Public Affairs Coordinator
307-637-6469 Direct
307-631-6539 Cell
elamb@cheyennebopu.org
www.cheyennebopu.org