The Town’s Sewage Plant, Adjoining Wetlands, & Surface Water Quality

Aerial view of Town of Jackson Wastewater Treatment Plant lagoons. Photo Credit: Town of Jackson

Written by Susan Scarlata | Town of Jackson

Sewage, also known as wastewater, is not something most people spend much time thinking about. That said, in Jackson, it’s only because the Town’s sewage system and wastewater treatment plant work so well that most people in the community rarely think about it. The treatment plant is located off Highway 191/89/26, between Jackson and Hoback Junction, not far from the confluence of Flat Creek and the Snake River. It is the largest sewage treatment plant in our area and keeps toilets flushing, sinks draining, and wastewater processed for residences and businesses in the Town and some of the County. 

The Town recently hosted a community meeting to share water quality data collected after treated sewage (effluent) moves through newly constructed wetlands adjacent to the plant. Before effluent reaches these wetlands, though, it goes through many treatment steps first. Here are the basics of how the Town’s treatment process works. Sewage arrives through a system of pipes and ends up at the treatment plant, where it is screened for trash, organic matter, and debris. It then flows into a series of ten lagoons or ponds where it is mixed and aerated. As it moves through the lagoons, organic waste is broken down by aerobic and anaerobic bacteria. Then, it undergoes ultraviolet (UV) treatment to further disinfect it and remove any lingering viruses and bacteria. The Town regularly tests effluent at this point in the process, which is required by our permitting agency, the Wyoming Department of Environmental Quality (DEQ). After the treatment processes outlined above, water quality levels meet or exceed DEQ standards. 

However, effluent continues its journey through more steps. After UV disinfection, it flows through a pond, where it is diluted with freshwater from a small creek, and then travels through three small wetland ponds. After that, effluent flows through the newly constructed wetlands mentioned above that the organization Ducks Unlimited constructed in 2023. Here, more nutrients like nitrates, phosphorus, and ammonia are removed from the effluent by natural and sustainable processes.

Two years ago, to gather additional data, set a baseline, and understand broader impacts of the treatment plant on the ecosystem, the Town began testing the effluent after it passes through the new wetlands. Though still preliminary, the first years of data collected show that water quality downstream of the new wetlands is within an even healthier range than samples taken after either UV treatment or the smaller wetlands. The data suggest that once effluent from the plant enters the Snake River, nitrate and ammonia concentrations are very low and are unlikely to be harmful to aquatic life. 

At the recent forum about this data, community members shared varied input from praising duckweed, a plant that helps process nitrates, to kudos about the new wetlands. There were also questions about testing groundwater, which the local organization Protect Our Water recently petitioned the DEQ to direct the Town to do. The Town is actively working with the DEQ to make this happen. One community member also shared that, “This is exactly the type of information sharing and transparency we need. This is an early analysis of what’s going on at the treatment plant. I applaud this effort. We all know there will be more demand on the plant. This study is effectively creating a baseline as more sewer line gets laid and an increasing load takes shape over time.” Town staff and electeds listened to and appreciate all the comments and perspectives shared, and will continue to consider them moving forward. As the Town and buildings in it are updated, infrastructure must be maintained and updated too.

The report with detailed data about surface water: “2024-2025 Wastewater Treatment Plant Wetlands Testing” including visuals, charts, graphs, and more is available on the Town’s website at: https://www.jacksonwy.gov/m/newsflash/home/detail/1288