Storm damage recovery

SW Alder-Harvey Milk Sewer Project

Sewer and Stormwater
Environmental Services is designing a project to repair 9,700 feet, or almost 2 miles, of aging public sewer pipes in downtown Portland. Having provided 140 years of service, the pipes require repairs to reduce risks of basement flooding and sewage releases to downtown buildings and streets.
Project design continues. Construction is anticipated to begin in March of 2025 and take a year and a half to complete.
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The SW Alder-Harvey Milk Sewer Project is the next in a series of projects to repair and replace aging public sewer pipes in downtown Portland that are in poor condition. The existing pipes were built between 1881 and 1974. They are showing signs of cracks, breaks, holes, offset connections, grease obstructions, and tree root intrusions. Timely repairs now will make them last another 80 years, increase their resiliency to earthquake damage, and provide safe and reliable sewer service to downtown Portland.

Project Area

The project boundary is from W Burnside Street to the north and SW Salmon Street to the south, and between SW Naito Parkway and SW 18th Avenue.

Between SW Alder and SW Harvey Milk streets from SW Naito Parkway to SW 13th Avenue.


Project design will continue through  2024. Construction is anticipated to begin in March of 2025 and take a year and a half to complete.

What's Happening Now

This project is in the design phase. Over the next several months, you may see crews in the project area to conduct a variety of activities, including pipe and maintenance hole inspections, root removal, pipe cleaning, survey work, utility locates, and soil and pavement sampling.

These activities may temporarily disrupt and delay traffic and will occur over time, not all at once. These activities will help confirm what pipes to repair or replace, what construction methods to use for each pipe, and how to avoid conflicts with other underground utilities during construction, including water, gas, and telecommunications lines.

Construction Methods

This project will use several construction methods to repair or replace public sewer pipes. Most of the methods will be trenchless, although some of those methods will require digging access pits to install pipes. Trenchless methods avoid having to dig deep and long trenches in downtown streets to replace whole pipes. The multiple underground utilities in the downtown area make major open trench excavation almost impossible. 

The project is currently designed to use the following construction methods:

  • Cured-in-Place-Pipe Lining (CIPP) to install liners that seal cracks, help prevent root intrusion, and restore the pipes to near-new condition.
  • Pipe Bursting and Pipe Reaming to replace and upsize public sewer pipes in SW Main Street and in SW 11th Avenue.
  • Horizontal Directional Drilling to construct sewer extensions and service laterals.
  • Open Trench Excavation to dig small trenches to replace short sections of broken pipe before repairing the entire mainline sewer pipe, and to construct sewer service laterals and access pits.
  • Vactor Excavation to install sewer cleanouts so that crews can access sewer connections to downtown buildings and maintain sewer service during repairs.

What to Expect

Environmental Services wants you to know what to expect during design and during construction so you can plan ahead and be prepared. Sewer construction is disruptive to those who live and work in a project area. The city's contractors take care to keep noise, dust, vibration, odor, traffic delays, and other potential construction nuisances to a minimum. They also set up safe work zones to protect crews and the public from the hazards associated with construction.

Learn more about What to Expect During Construction.

Site Visits and Building Investigations

Environmental Services and its contractors may need to enter buildings in the project area to gather information that will help them design and construct necessary sewer repairs. They may need access for any or all of the following activities:

  • Locate, inspect, and evaluate sewer and stormwater pipes and connections, sewer service laterals, cleanouts, sump pumps, and other private plumbing facilities.
  • Determine basement and sub-basement layouts, utility vault locations and elevators, parking garage layouts, and other private property features.
  • Survey existing sewers on private properties.
  • Identify and mark utilities in areas surrounding the sewer.
  • Collect and analyze soil and water samples.

Environmental Services and its contractors will coordinate with building managers and property owners to schedule site visits, arrange access, and conduct investigations as needed.

We Want to Hear from You

During the design phase, Environmental Services will work with the community to provide information about the project and identify concerns. Downtown property owners, businesses, and residents can inform decisions and help the project team with the following: 

  • Identify project stakeholders, including property managers, facility managers, and business operators. 
  • Identify local issues, community concerns, special events, and access needs. 
  • Develop reasonable solutions to community concerns and construction impacts. 
  • Provide input on regular daytime (7 a.m. to 6 p.m.) and nighttime (6 p.m. to 7 a.m.)  construction work hours. 
  • Provide information about private property sewer connections and plumbing facilities. 
  • Identify and meet the needs of individual downtown businesses, residents, property owners, and property managers. 

Environmental Services will inform residents and businesses about project activities and respond to questions and concerns in a timely manner. The following resources will help you stay informed and report concerns: 

  • Questions: Call 503-823-5315, stating that SW Alder-Harvey Milk is your area of concern. Outreach staff will return your call by the next business day. 
  • Sewer Emergency: In the event of a sewer backup or basement flooding, call the Maintenance hotline immediately at 503-823-1700. It is staffed all hours and all days, 24/7.
  • Other Projects: Learn about other downtown sewer repair projects.

Project Background

The SW Alder-Harvey Milk Sewer Project is being designed to accomplish the following sewer improvements: 

  • Repair 9,700 feet, or almost 2 miles, of aging public sewer pipes within W Burnside Street to the north and SW Salmon Street to the south, and between SW Naito Parkway and SW 18th Avenue. 
  • Clear roots and flush debris from public sewer pipes in the project area. 
  • Repair, replace, or add maintenance holes as needed. 
  • Install cleanouts on sewer service laterals to high-rise buildings to enable future sewer maintenance access. 
  • Repair or replace active sewer service laterals for individual property connections. 
  • Assist and support customers with nonconforming sewer connections to achieve the recommended sewer connection for their property. 

In addition, Environmental Services will collaborate with the Portland Water Bureau where possible to replace their water lines with earthquake resistant pipe. Construction in downtown Portland requires coordination with multiple partners.

Sign Up for Updates

Sign up for regular email or text message updates for the SW Alder-Harvey Milk Sewer Project through our free GovDelivery subscription service. These updates are the best way to stay informed about what’s happening and what to expect. You can also sign up for bulletins on other projects and topics.

This project will help protect the health of the Willamette River Watershed.