To protect our state’s vital aquatic habitat, the Oregon Department of Environmental Quality has mandated new limits on the total maximum daily loads (TMDLs) that public and private entities can place into the Willamette River, intended to lower river temperature and remove additional pollutants before the treated water is safely returned to rivers and streams. Increasingly higher temperatures in the river have contributed to declines in coldwater fish species such as salmon and trout.
In response, Albany and Millersburg partnered with ATI to solve this common challenge. Discharge from the Albany-Millersburg Water Reclamation Facility (WRF) is approximately 5°F too hot to meet the new limit. The wastewater entering the Albany-Millersburg WRF is warm primarily because of water heaters from homes and businesses; in summer, it is about 72°F. While the water is being treated at the WRF, the biological process and energy added with pumped air increases the temperature another degree. The temperature of flow discharged from ATI Wah Chang is similar. DEQ’s summer fish passage water temperature limit at Albany is 68°F.
In addition, ATI Wah Chang was required to relocate its point of discharge, established in 1956, from a tributary stream to the Willamette River. This created a situation where yet another effluent diffuser would need to be permitted, constructed, operated, and maintained in the Willamette River.
The partners explored many options with CH2M Hill including treatment plant upgrades, storage and cooling towers, refrigeration, land application reuse, new outfall diffusers, and treatment wetlands. An integrated wetland treatment system gave the cities and ATI Wah Chang the opportunity to achieve discharge limits, share costs, and produce greater overall economic, social, and environmental benefits for the community. Their innovative solution has done more than just additionally treat the water: it has provided an attractive, environmentally robust public-use site for recreation and learning.
An environmentally sound solution delivering community benefits