Infrastructure Project Will Replace Water Pipeline Spanning Marys River
July 1, 2025 - The City of Corvallis Public Works Department is launching a major project this summer to replace and upgrade a large water pipeline that crosses the Marys River and delivers treated drinking water to the north and northwest portions of Corvallis.
Most drinking water in Corvallis is produced at the Taylor Treatment Plant on the south side of the City. Water from the Taylor plant is delivered to customers on the north side of town through a 20-inch cast iron pipe attached to the 4th Street bridge over the Marys River near Shawala Point.
This water pipeline was identified as being particularly vulnerable in the event of an earthquake. City engineers have been working to develop a plan to replace the pipe with a larger 42-inch pipeline, which will be placed underground to provide seismic resiliency.
The plan involves digging a trench into the bottom of Marys River up to a depth of 8 feet to lay the new pipe. The trench will then be filled, and the riverbed restored to its previous condition.
Starting in July, contractors will be installing temporary barriers to divert the river water around the work site. The Marys River will be closed to recreational use while contractors are working in the waterway. Postings for the river closure will be located at Avery Park, Willamette Boat Landing and North Riverfront Park. The multi-use path along the Marys River will remain open to pedestrian and bicycle traffic during construction. Periodic traffic control measures around 4th Street may be in place at times in the upcoming months.
After the work is completed, the riverbank and vegetation will be restored accordingly. This project was scheduled during the summer months, when water levels are expected to be at their lowest, to reduce the impact on the river habitat.
“This is really a once-in-a-generation capital improvement project,” said Josh Bjornstedt, the civil engineer leading the project for the Public Works Department. “The improvements we’re making this summer will ensure a safe and resilient water system for the Corvallis community heading into the future.”
The project is estimated to cost about $4 million to complete, with funding split between water utility fees paid by water customers and system development charges. For more information on the project, contact Josh Bjornstedt at 541-766-6731 or email josh.bjornstedt@corvallisoregon.gov.
