Spokane River Bed Washing Out Beneath Argonne Road Bridge

Little more than a month after the Argonne underpass opened to elated drivers, engineers are turning their attention to another trouble spot on the primary route into the Valley from the north.

The current of the Spokane River is eating away at the Argonne Road bridge, said county Engineer Bill Johns.

On Tuesday, county commissioners approved spending up to $70,000 to fix the problem. Johns did not know when work would begin, but said the project should take about a week and be done by winter.

The four-lane bridge won’t be closed, he said, although traffic may be restricted to three lanes at times.

The problem was noticed several years ago, and has been monitored since. An inspection last week showed that it has grown much worse in recent months.

The inspector, who used scuba-diving gear to check out the bridge abutments, reported the river bed has washed out from under concrete footings in places. Some gaps are large enough for a man to swim through, Johns said.

“This isn’t a sky-is-falling message,” said Dennis Scott, county director of public works. “We’re saying we noticed something, we want to fix it.”

If it isn’t fixed soon, Johns said, “the bridge would collapse,” although there’s no telling when.

“If we have another (river) flow like we did last spring, that might do it,” said Ross Kelly, an engineer on Johns’ staff.

The Argonne bridge was expanded to four lanes in 1972. It is the newer portion, which takes the brunt of the current, that needs repairs.

About 40,000 cars use Argonne each day.

, DataTimes