Sanitary Sewer Overflow on NW Jetty Ave. and Force Main Leaks on SE Inlet and Hwy 101
Tuesday, December 9, 2025, the Wecoma sewer lift station (located at NW Jetty near NW 34th Street) became overwhelmed despite all pumps running at 100%. This caused a Sanitary Sewer Overflow (SSO) from two upstream manholes near the NW 34th Street beach access. Oregon Emergency Response System was notified, and it was assigned OERS# 2025-3081. The Department of Environmental Quality was also notified. The manholes were coned off, and contaminated water signs were placed. Fecal Coliform monitoring began the next morning (12-10-25) and showed high results. The overflow stopped at some point early on December 11, 2025. Results remained high on December 11 but dropped down below the required minimum reading in samples taken on December 12 and 13. Staff estimates the SSO volume was approximately 20,000 gallons.
Friday, December 12, 2025, a force main leak in the line coming from the SE 3rd Street sewer lift station (also ran 100% for most of the week) manifested itself on SE Inlet Ave. Crews were notified by dispatch at 4 pm. and responded immediately. Sewer and water staff arrived on site and began to locate the actual leak. With the help of John Thompson Excavation, the crew began digging and found the leak site. A band was placed on the 16-inch ductile iron pipeline, and the excavation was backfilled. This was completed at 3 am on Saturday December 13, 2025. Staff estimate the SSO volume to be between 10,000 and15,000 gallons.
The same force main formed a second leak in Hwy 101, near SE East Devils Lake Road. We have hired K&E Excavation to assist with locating and repairing the leak. Staff estimates this SSO will be between 30,000 and 35,000 gallons.
We avoided any discharge violations at the Wastewater Treatment Plant despite the heavy rainfall. The crew divided up shifts 24/7 throughout the week, while also working their normal daily shifts to closely monitor and manually operate aspects of the plant.
Rainfall data collected at the Wastewater Treatment Plant from December 1 to December 10, 2025 is shown below.
Monday, December 1 = 0.10 inches of rain
Tuesday, December 2 = 0.30 inches of rain
Wednesday, December 3 = 0.10 inches of rain
Thursday. December 4 = 2.10 inches of rain
Friday, December 5 = 3.20 inches of rain
Saturday, December 6 = 1.40 inches of rain
Sunday, December 7 = 0.90 inches of rain
Monday, December 8 = 7.20 inches of rain
Tuesday, December 9 = 4.20 inches of rain
Wednesday, December 10 = 1.1.0 inches of rain
Total = 20.60 inches of rain
