Choosing a route for 26 miles of pipeline is a challenging juggling act, consultants say

Tualatin Valley Water District planners remain hard at work figuring out how to route a series of water pipelines from Wilsonville to various locations in the metro area.

Part of a $1 billion-plus regional project that is envisioned to bring fresh Willamette River water to a half-dozen or more metro cities by 2035, planning for the proposed 26 miles of pipe remains in the early stages. But because of its water treatment plant and key location on the river Wilsonville is likely to remain engaged in the process the entire way.

“We probably have 40 or 50 different criteria grouped into 10 different headings,” Jeff Fox, a consultant for the water district, told the Wilsonville City Council Aug. 4.

They include community acceptance, impact on the communities involved, environmental and permitting issues, constructability, operations and maintenance, system resiliency in the face of emergency and more.

“They are still in draft form,” Fox said. “We’re working hard to finalize those.”

Once the criteria are settled, the real chore of selecting feasible pipeline routes will begin in earnest. Multiple feasible routes will be chosen along the way, with a final preferred route likely to be singled out by October. After that, public outreach about the proposed water plan will increase in Wilsonville and other communities.

“We have not finalized the criteria yet,” said Todd Heidgerken, community and intergovernmental relations manager for the water district. “We’re not approaching this simply from the straightest line and cheapest cost, but that there are various ways to balance the process.”

Three major questions are in play during the routing process, Fox said. One: is the route acceptable; two: is the route feasible from a construction standpoint; and three: how can the water district manage costs for ratepayers, both in construction and future operations and maintenance.

To minimize future disruption for residents in the path of the new pipelines, the district also will be looking to team up with parks, trails and road projects that are planned for the same areas. This will minimize interruptions to local residents and simplify construction.

Finally, one of the major goals of the project is to wind up with finished infrastructure that is able to withstand a major earthquake or other natural disaster, even a magnitude 9.0 Cascadia subduction zone quake.

Wilsonville Mayor Tim Knapp asked if a final preferred alternative would be selected by October.

“Will you have a pipeline route identified?” Knapp asked. “The public wants to know ‘How will it impact me?’”

Heidgerken said he hopes to have an answer by then, but he emphasized that between now and then public input from those cities will be crucial to any decisions that are made.

“We’re not going forward and saying ‘this is the route,’” he said. “This is where your feedback would be helpful.”

The water district plans over the next six years to plan and design both a new and expanded water treatment plant in Wilsonville together with the city of Hillsboro and a 26-mile network of pipeline and reservoirs. Construction would tentatively start in 2021 and take five more years to complete. Water would then begin flowing to Hillsboro and other cities that get water from the TVWD by 2026.

Contract Publishing

Go to top
Template by JoomlaShine