Sewer Construction Methods

Guide
Photograph of construction on Hawthorne Boulevard and 48th Avenue in the street, demonstrating an open trench excavation. There is a yellow excavator digging near the curb, and two tipper trucks with soil and equipment inside.
Environmental Services repairs more than 50,000 feet of pipe each year using a variety of sewer construction methods. Each method creates different levels of noise and disruption to neighborhood activities. Learn more about sewer construction methods.

Portland’s sewer collection and treatment system includes more than 2,500 miles of sewer pipes. About one-third of those pipes are 80 years old or older.  

Environmental Services and our contractors are working throughout Portland neighborhoods to repair and replace critical sections of deteriorating sewer pipes. Timely repairs will protect public health and the environment by reducing the risk of sewage releases to buildings, streets, greenspaces, rivers, and streams.  

For some projects, traditional open trench sewer construction is the only feasible construction method available. But when possible, Environmental Services uses trenchless methods such as cured-in-place pipe lining, spiral wound pipe liningpipe bursting, pipe reaminghorizontal directional drillingmicrotunneling, and jack and bore.

Sometimes, projects require a combination of trenchless and open trench construction to repair and replace sewer pipes. Trenchless methods can minimize disruption to sidewalks, curbs, streets, traffic, and other utilities, and reduce impacts on the neighborhood.