Aldercrest Landslide Repair

Project description: The county initially closed SE Aldercrest Road on Feb. 14, 2019, when the landslide occurred. After a thorough investigation, the road failure was determined to be caused by groundwater seepage nine feet below the road surface. Crews will build a retaining wall and manage groundwater with a drainage system below the road. Clackamas River Water will also be on site to replace the existing water line.

Updated: 10/30/19

Status: Construction complete


  • Construction start: Oct. 2019; Crews will be onsite 7:30 a.m. – 4 p.m., Monday through Friday
  • Construction complete: Oct 30, 2019

Things to be aware of:

  • There will be vehicle traffic impacts during construction of this project.
  • The roadway continues to be unsafe for vehicle traffic, so we ask that everyone please respect and obey the closure signs and barriers, and follow the Thiessen/Oatfield detour route. The road closure and detour will remain in place until the repair is complete. Local traffic and emergency vehicles will still have access up to the work zone.


  • Funding is provided from Clackamas County Road Funds.

Thank you for your patience during this extended closure. We realize this is an inconvenience and appreciate your cooperation to help keep all travelers safe.

Department Staff
Jon Sparks
Project Manager
503 -650-3235


McCoy Building 902 Abernethy Road Oregon City, OR 97045

Office Hours:

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