Fixing the Unseen: Water Pipeline Replacement in Unincorporated Eugene
A new portion of pipeline is put into place by EWEB's water construction team.
--
How do you maintain 800 miles of something you can’t see? Sounds like a riddle, but this is everyday life for Chris Irvin, Water Engineer, and overseer of EWEB’s network of water distribution pipelines.
Water pipelines are buried underground, crisscrossing Eugene and delivering water to 63,000 homes and businesses. Many of the pipelines were installed from the 1950s to the 1970s and are inching closer and closer to the end of their useful lives. When charted out, replacement needs look like a bell curve, said Irvin.
“We're coming into the steep part of the curve,” he said. “A lot of our system is aging into the realm of replacement.”
To parse out what pipes need to be replaced first, Irvin relies on an internal model that uses data – like material, age, and history of breakage – to pinpoint pipelines that are most likely to fail. At the top of that list last year was a water pipeline on Azalea Drive in northwest Eugene. The pipeline had leaked and been repaired eight times since it was constructed in 1950.
EWEB's water distribution model.
Working with Independent Water Districts
The discovery presented a new riddle. How do you fix something that belongs to others?
The Azalea pipeline is in an unincorporated area of Eugene’s Santa Clara neighborhood. The pipes and fire hydrants are owned by an independent entity called the Santa Clara Water District. The SCWD buys wholesale water from EWEB and delivers it to customers through their self-owned pipeline network.
SCWD is governed by a volunteer board and doesn’t have any full-time employees. EWEB has a long-standing relationship with SCWD and provides planning, engineering, and construction services to help them maintain their water assets. SCWD pays EWEB for the services rendered, rather than going to an outside consultant for pipeline work.
“The district gets good bang for their buck in terms of how much pipe they get in the ground,” said Irvin, “because EWEB is adept at pipeline design and construction, and it alleviates the burden on the district to manage consultants and contractors.”
EWEB also benefits because it can ensure the quality of new pipe being added to the system. Although they have separate ownership, EWEB pipes and SCWD pipes are intertwined hydraulically, so consistency in design is important.
A Productive Partnership
The Azalea line that is being replaced was originally 6” in diameter that tapered down to 2” in some places. Construction is now underway to upsize the pipe to 8” and install new hydrants to improve water flow for firefighters. New standards for earthquake resiliency, like reinforced joints, are also being implemented. The project is estimated to cost a little under $300k, which will be paid by SCWD’s ~4,000 customers over time.
EWEB water construction workers fill a portion of the water pipeline trench on Azalea Drive.
Although it is a unique arrangement, Irvin said the partnership with SCWD is working well.
“They have the same bell curve problem as us,” said Irvin, “with all their pipes getting older and trying to spend money wisely. We've done a great job of replacing some pretty problematic pipes together over the last few years.”
EWEB has a similar partnership with the River Road Water District which serves unincorporated areas of Eugene’s River Road neighborhood.
For more information on how EWEB is working to safeguard your water, visit https://www.eweb.org/waterreliability.
