Natural Municipal Wastewater Treatment System
When the City of Ouray decided to upgrade their wastewater infrastructure in 1992, they turned to Biohabitats to employ a natural systems approach to provide high quality effluent for discharge into the Uncompahgre River, create habitat/sanctuary for birds, reduce odors, and to be aesthetically pleasing. The resultant wastewater treatment facility, at the time the largest of its kind at this elevation and within the State of Colorado, combines the technologies of aerated lagoons and constructed wetlands. Located at 7,480 feet in the San Juan Mountains of Southwestern Colorado, the facility needed to be robust enough to function at high elevation with extreme wintertime lows. The treatment facility is designed for a flow of 363,000 gallons per day.
Primary treatment is provided by a partial mix, two cell aerated lagoon, which is operated to provide substantial reduction of organic loading prior to polishing in the wetlands. The wetlands’ cells are designed to complete treatment to surface water discharge standards. Operating data showed that the system was efficient at reducing fecal coliform counts, therefore minimizing pressure on and improving the efficiency of the chlorine disinfection system.