In the spring of 2017, Environmental Services completed Phase One of a project to repair about 3,200 feet of 100 to 140-year-old public sewer pipes in SW Yamhill and SW Morrison Streets in downtown Portland that were in deteriorating condition. 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.
Phase Two will repair another 2,700 feet (0.5 mile) of public sewer pipes in areas that were identified as high risk, where crews were not able to safely bypass sewage flows from adjacent properties to repair the public sewer in the street this past spring. The three-week light rail closure wasn't enough time to complete that challenging work. Environmental Services has been working with those properties to plan repairs at the locations shown in the map below.
Public sewer pipe repairs will resume at the above locations beginning February 2018 and may continue intermittently through the summer and fall of 2018. Construction hours may vary throughout the project, with some work to take place after 6 p.m. and before 7 a.m. to reduce traffic congestion, create a safer work zone, and allow time for the new sewer pipe lining to harden.
Project Accomplishments - 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
While the majority of the project was able to be accomplished in the short time period, some future work will be necessary to ensure high quality infrastructure for our community, including:
- Repairing mainline public sewer pipes in challenging locations not repaired with this project
- Determining how to bypass sewer flows in challenging locations for future repairs
- Repairing public service laterals to adjacent buildings on SW Yamhill and SW Morrison Streets
- Working with private properties to determine potential private plumbing modifications necessary to complete public sewer repairs