WEST EXTENSION IRRIGATION DISTRICT/CITY OF HERMISTON
CLASS A WATER REUSE PROJECT
West Extension began receiving the City of Hermiston’s class A recycled water from their new waste water treatment plant on August 16th, 2016. The Governor’s Water Resources Commission had a joint meeting with the Environmental Quality Commission in Hermiston August 18-19, and were on hand to celebrate the occasion in addition to touring other ag-related issues in town.
The City of Hermiston invested years seeking a long-term solution to discharge its Class A recycled water during the summer irrigation season. New discharge regulations designed to protect salmon in the Umatilla River left the City unable to discharge to the river during this period. During the same timeframe, West Extension Irrigation District (WEID) observed flows decreasing in the Umatilla River, which limited their ability to withdraw critical irrigation supplies. Discussions between the City and the District began in 2007 to determine if a mutually beneficial arrangement could be created. WEID first had to be assured that the recycled water was compatible for their use, not create a burden to its irrigators and would provide clear benefits to its farmers and landowners. To address these concerns the City and the District worked closely with WEID’s partner, the Bureau of Reclamation. They interfaced with several governmental/public agencies including the Oregon Farm Bureau, Oregon Tilth, the Confederated Tribes of the Umatilla Indian Reservation, Oregon Fish and Wildlife, the Department of Environmental Quality (DEQ), and National Marine Fisheries to perform environmental reviews and develop a regulatory framework for the process.
After all processes, reviews and permits were complete, WEID began receiving water from the Hermiston Recycle Water Treatment plant in the summer of 2016.
The recycled water meets the most rigorous quality standards in the industry, termed “Class A Recycled Water.” To continuously meet Class A standards the City invested $27 million in its Membrane Bioreactor Treatment System that produces water that is virtually indistinguishable from drinking water. For example, drinking water for human consumption must have turbidity (a measure of cloudiness of the water) of less than 0.3 turbidity units over 95% of the time. The new Recycled Water Plant will routinely produce a turbidity of less than 0.1 turbidity units.
The project will reliably meet NPDES permit levels for the next 20+ years; increase treatment capacity from roughly 1.7 MGD to 3.0 MGD to match projected population growth in the service area by 2026; address environmental concerns impacting the Umatilla River and threatened salmonid species; and discharge the highest quality Class A Recycled Water to the Umatilla River.
The City monitors the turbidity continuously at the treatment plant. A system is in place wherein automatic alarms and shut-downs occur when the turbidity exceeds 0.5 NTU. The total coliforms are monitored daily.
Customers of WEID are invited to tour the Hermiston Recycle Water Plant facilities. Please contact WEID Manager, Bev Bridgewater, to arrange for a tour.