Portland eyes $57 million project for earthquake-ready pipeline under Willamette RiverPortland's west side could have a water problem if -- or when -- the Big One hits.
The Bull Run watershed 26 miles east of downtown provides drinking water to nearly 1 million customers in the metro area, and that water crosses the Willamette River at six locations.
But the pipelines serving downtown Portland and the Washington Park reservoirs are an average of 77 years old. Two are buried in shallow and unstable soil in the riverbed. Two more 24-inch pipes are attached to the Ross Island Bridge, which is expected to fail during a big earthquake.
All of those pipelines were designed before the city knew Portland could experience a catastrophic earthquake.
The city's 130,000 westside customers could be without potable water for six months or longer if and when the Cascadia Subduction Zone ruptures. The last time that occurred, geologists estimate it produced at least a 9.0 magnitude earthquake.
Portland is preparing for that harsh reality by moving forward with a $57 million project to build a 42-inch pipe 80 feet beneath the Willamette River.
Portland hopes to begin construction in the summer of 2017 and finish by 2019.
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