August 16, 2023 - Environmental Services reopened SE Yamhill Street to all traffic today between SE 74th and 76th avenues following emergency repairs to a 1914-era sewer pipe and surrounding infrastructure.
The two-block stretch has been closed to vehicles since May after a large sinkhole opened up on a Friday evening. Crews immediately responded and worked through the May 12 weekend to stabilize the sinkhole. Environmental Services engineers then determined the need for extensive repairs to ensure the stability of the 10-foot-deep aging clay sewer main pipe, as well as make repairs to the connecting maintenance hole.
Engineers ordered a custom-sized 16-inch liner to strengthen the clay sewer pipe and extend its useful life by at least two decades. Crews installed the liner, repaired damage to the maintenance access hole, and checked for and then filled additional smaller cavities that had opened up underground along the pipe length.
Final paving concluded earlier today and the roadway is open.
Traffic Advisory Update: Repairs continue on SE Yamhill Street and 74th Avenue after sinkhole opened up in spring
July 26, 2023 - Environmental Services continues to work with suppliers and contractors to repair the complex sinkhole that opened up this spring on SE Yamhill Street, leading to a street closure between SE 74th and 76th avenues. Repairs are expected to continue over several weeks.
For the safety of the public, the street remains closed with steel plates covering a hole that spans about four feet by eight feet. Underneath that surface, BES engineers have determined that the cavity is much larger, extending an estimated 50 feet wide and 10 feet deep, affecting a 1914-era sewer pipe and a maintenance hole at the SE 76th Avenue intersection.
While City crews immediately investigated and stabilized the site during the May weekend when the sinkhole appeared, the timeframe for full repairs remain in flux due to countrywide supply chain delays, and the complexity of a sinkhole of this size and the age of the infrastructure.
The following repairs are underway:
- A custom-sized liner has been ordered for installation in the 1914-era sewer pipe to ensure its stability and extend its service life. Manufacturing is complete. Delivery is in progress.
- When the 340-foot-long liner arrives, crews will be on scene for several weeks for installation.
- Crews will make additional repairs to the base of the maintenance hole at the SE 76th Avenue intersection, a repair that will be possible after the liner is installed.
- Crews will then fill the cavity in stages to ensure the stability of the ground and street.
- The final stage will be paving.
Sidewalks are open for people walking, bicycling, and rolling. TriMet Bus #15 remains detoured to SE Taylor Street. During certain stages of repair in the coming weeks, BES may open the street to limited use when safe to do so.
The original news release and previous updates are found here.
Environmental Services - the City of Portland’s sewer and stormwater utility - protects public health and the environment by collecting and recovering resources from the city’s wastewater, managing stormwater, and restoring and protecting Portland’s rivers, streams, and watersheds.