Environmental Services has completed construction on a project to repair 100 to 140-year-old, deteriorating public sewer pipes in SW Yamhill and SW Morrison streets in downtown Portland. Repairs will protect the public and the environment by reducing the possibility of sewage releases to buildings and streets.
Phases of Work
In the spring of 2017, Environmental Services completed Phase One of sewer repairs on 100 to 140-year-old, deteriorating public sewer pipes in SW Yamhill and SW Morrison streets between SW 1st and SW 13th avenues in downtown Portland. The sewer pipes were showing signs of cracks, breaks, holes, offset pipe connections, and root and grease obstructions, putting the pipes at risk of structural failure. During TriMet's MAX Improvement Project, which closed light rail on SW Yamhill and SW Morrison streets, the City repaired 3,200 feet of sewer pipes under the light rail tracks.
In the summer of 2018, Environmental Services completed Phase Two of sewer repairs on public sewer pipes in SW Yamhill and SW Morrison streets. Repairs to an additional 2,700 feet of sewer pipes in high-risk areas required coordination with adjacent private properties to safely bypass sewage flows from those buildings and repair the sewer pipes in the street. The three-week light rail closure in the spring of 2017 was not enough time to complete that challenging work.
In the fall of 2019, Environmental Services completed Phase Three of sewer repairs on public sewer pipes in SW Yamhill and SW Morrison streets. Five remaining mainline sewer pipe segments were repaired along with service laterals connected to them. Originally scheduled for the fall of 2018, the repairs were postponed due to the challenging nature of the pipes, difficult access issues, and availability of subcontractors and materials.
The map below indicates remaining sewer pipe repair work locations.
Phase One, Spring 2017
Environmental Services set out to do a large-scale sewer repair project in a short amount of time. TriMet’s MAX Improvement Project gave us the rare chance to work on underground sewer pipes that cannot be accessed while overhead high-voltage power lines are live and light rail trains are running.
In the three weeks that light rail was out of service, the city’s contractor was able to accomplish the following repairs and address immediate needs to extend the life span of sewer pipes in the project area:
- Inspected 4,500 feet (0.85 mile) of mainline public sewer pipes and service laterals
- Cleared roots and flushed debris from approximately 4,500 feet (0.85 mile) of public sewer pipes and service laterals
- Installed 3,200 feet (0.6 mile) of cured-in-place-pipe lining to repair mainline public sewer pipes
- Investigated over 30 public service laterals to locate where adjacent buildings are connected to the mainline public sewer
- Installed 25 sewer cleanouts to provide bypass sewer service during the pipe lining process and to provide access for future sewer maintenance activities
Phase Two, Summer 2018
While the majority of the SW Yamhill-Morrison project was able to be accomplished in the short time period of Phase One, additional work was necessary to ensure high quality infrastructure for downtown properties. Phase Two accomplishments included the following:
- Repaired mainline public sewer pipes in challenging locations not repaired in Phase One
- Installed 2,700 feet (0.5 mile) of cured-in-place-pipe lining to repair mainline public sewer pipes
- Determined how to bypass sewer flows in challenging locations for future repairs
- Repaired public service laterals to adjacent buildings on SW Yamhill and SW Morrison Streets
- Worked with private properties to determine potential private plumbing modifications necessary to complete public sewer repairs
Phase Three, Fall 2019
Five remaining public sewer pipe segments were repaired, along with the service laterals connected to them. The five public sewer pipes repaired were in SW Yamhill and SW Morrison streets, between SW 2nd and SW 10th avenues.