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 repaired 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 worked with those properties to plan and construct sewer repairs.
Another phase of work will be necessary to complete work at locations labeled FALL 2018 on the map below. Phase Three work has been delayed and is anticipated to occur sometime in 2019.
Repairs to the remaining pipes will restart sometime in 2019. Environmental Services will notify property owners, businesses, and residents in the project area when the work is scheduled.
Repairs at each location should take less than a week, with a combination of daytime and nighttime work approved by the Portland Noise Office. TriMet light rail service will not be affected.
Project Accomplishments - Spring 2017, Phase One
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
Project Accomplishments - Phase Two
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, 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
Phase Three - To Be Scheduled
Five pipe segments remain to be repaired, labeled FALL 2018 on the map.