Wastewater

Located at 635 S Fir, the City operates a state-certified laboratory and performs all required tests on site.  The Sewer plant employs 2 full-time staff members that support and maintain operation compliance and lab work.  The City of Omak Wastewater Treatment Plant operations is a team effort under the direction of Jesus Arciniega.  In 2014, the City and Chief Operator Jesus Arciniega received the Wastewater Treatment Plant Outstanding Performance Award for the ninth consecutive year from the Department of Ecology.

Sewer Background & Inventory

The City of Omak provides central sewer treatment services to all areas within the corporate limits.  The sewer collection and treatment facility is a typical activated sludge oxidation ditch system with outfall to the Okanogan River.  According to the City engineers, the collection system is well laid out with good configuration on trunk and interceptor lines coupled with feeder of collector laterals.  The City's system includes over 24 miles of gravity sewer pipe, approximately 0.3 miles of force main pipe, four sewage lift stations, and associated telemetry.

Sludge Disposal

Most of the bio-solids are Class "B" dewatered bio-solids hauled form the plant and stored for land application on property northeast of the City.  Below are photos of the process.  If you have questions about the process, contact Chief Operator, Jesus Arciniega.

Sewer Collection System  & Improvements

The City owns approximately 24 miles of sewer collection lines, of which 20.8 miles are fifty to eighty year old concrete pipes.  In November of 2009, a sewer interceptor line on East Dewberry between Maple and Locust Streets failed, causing a sewage backup and overflow.  Again in March 2011, the same line failed further down.  The excavation of the Dewberry interceptor line revealed significant deterioration of the old concrete pipe.  Since then, the City of Omak assisted by city engineers, Gray & Osborne, Inc. have been inspecting, planning and designing.  The City was successful in obtaining loans from the Public Works Board and the Department of Ecology to fund and have completed Phase 1 and 2.  The City is continuing to replace sewer lines and side sewers as the funding becomes available.

BOD-5 (Biochemical Oxygen Demand) Testing

BOD-5 is one of the most important tests.  This test is used to see how efficient your plant process is.  Thousands of tests are performed each year to the influent and effluent to ensure we are in compliance with the Department of Ecology and Environmental Protection Agency.  After we ensure the tests meet the agency requirements, the effluent is discharged to the receiving waters in our case, the Okanogan River.