On Tuesday, June 4, 2024, in response to the release of treated wastewater from the Town of Hudson’s lagoons in late May, WDEQ conducted monitoring of Escherichia coli (E. coli), an indicator used to determine potential risks due to waterborne pathogens, at four recreation sites in Boysen Reservoir within Boysen State Park (please refer to map). The results indicate an elevated risk of illness for recreators engaging in immersion or immersion-like activities such as swimming or water play at the Lake Side Area. The Lake Side Area is located at the southern end of Boysen Reservoir near the US Highway 26 bridge.
Most strains of E. coli do not cause illness. However, E. coli is commonly used to indicate the potential presence of fecal contamination from humans or other warm-blooded animals. Due to the number of potential sources of E. coli, elevated concentrations have been found in several waterbodies in Wyoming, particularly during runoff events. Given the distance water would travel between the Town of Hudson and the Lake Side Area, more than 30 miles, as well as other potential sources of E. coli, the concentrations of E. coli observed at the Lake Side Area on June 4, 2024, may not be associated with the Town of Hudon’s release.
Elevated risk of illness for recreators was not detected further north in the reservoir at the Sandy Hills Campground, Fremont Bay Campground, or Tough Creek Campground.
DEQ is working with health officials and Boysen State Park to post signs at the Lake Side Day Use Area to notify recreators of the elevated health risks. DEQ will conduct additional monitoring as necessary.
EPA Region 8 implements the drinking water program in Wyoming. The DEQ contacted EPA Region 8 to determine if there were any downstream drinking water intakes that could possibly be impacted. Based on discussions with EPA, there are no drinking water intakes that would have been impacted from the Hudson discharge. The Town of Hudson obtains its drinking water from a series of groundwater wells located upstream of where the release occurred. Drinking water systems for downstream communities obtain water from groundwater wells or surface waters not impacted by the discharge. All public water systems are required to treat water to drinking water standards established by EPA.
Updates will be provided as needed. We encourage the public to refer to DEQ’s “News” section on the agency’s website at www.deq.wyoming.gov
