Environmental Services will construct repairs for about 6,500 feet of public sewer pipes in Downtown Portland that are 100 to 140 years old and in deteriorating condition. The sewer pipes are showing signs of cracks, breaks, holes, offset pipe connections, and root and grease obstructions, putting the pipes at risk of structural failure. The repairs will protect the public and the environment by reducing the possibility of sewage releases to buildings and streets.
Repairs will be made to pipes in SW Yamhill and SW Morrison Streets between SW 1st and SW 13th Avenues, plus a small segment on SW Stark Street at SW 1st Avenue.
Sewer repairs will occur this spring from March 15 to May 20, with the most challenging work being coordinated with TriMet's MAX improvement project in May. Coordination between the City and TriMet will minimize disruption to residents, businesses and visitors to downtown.
The Portland Noise Office granted Environmental Services a Noise Variance to enable the city's contractors to work all hours and all days, with the noisiest work restricted to daytime hours. A 24/7 schedule will condense several months of urgent sewer repairs into just nine weeks.
To avoid digging up streets and sidewalks for sewer repairs, the city will employ a process called Cured-in-Place-Pipe Lining (CIPP). Work crews access the sewer from manholes to insert a flexible liner inside the old pipe. Hot water or steam inflates and cures the liner, which gradually hardens to form a rigid, smooth surface that seals cracks and restores the pipe to near-new condition. This less disruptive process is also considerably less noisy than open trench excavation. CIPP will strengthen and reinforce the pipes, making them last for many years.
People who live and work near a CIPP repair project can sometimes smell a chemical odor during the pipe-lining work. The odor is from the chemical styrene, which is in the resin liner installed inside the pipe. The odor dissipates quickly once the installation process is complete. The amount of airborne styrene produced by the lining process is not expected to cause health issues for workers or the public. See www.portlandoregon.gov/bes/methods for more details about CIPP.
What to Expect during Construction
You can expect the following activities and impacts with this sewer repair project:
- Construction creates noise, vibration, and dust and disrupts normal activity.
- Accessing sewer pipes through manholes will require temporary street closures of one-to-two-block segments on SW Yamhill and SW Morrison Streets.
- Local access to all properties will be maintained or provided by flaggers.
- You should expect traffic delays in and near the work area.
- Staging areas for materials and construction vehicles will be on cross streets and will require some lane closures and parking removal.
- Bypass pumping to maintain sewer service during construction may require temporary cross-street closures with local access provided by flaggers.
- On‐street parking will be restricted in and near the work zones to create a safe work environment and to stage equipment and materials.
- Some equipment and materials may be stored on the street overnight.
- A city inspector will be on-site during work hours and may be able to assist you with an immediate need during construction.
- Sewer, water, and other utilities will remain in service during construction.