Duwamish River community advocate Paulina López and former Mayor Greg Nickels will co-chair a new task force to deal with the traffic mess caused by the cracked West Seattle Bridge, and give opinions about repair or replacement options.

López is executive director of the Duwamish River Cleanup Coalition, a nonprofit that organizes environmental events and speaks for neighborhoods next to the polluted river, a 5.5-mile-long federal Superfund site. Georgetown and South Park residents there expect a plague of traffic, now that many of the usual 125,000 daily travelers on the high-rise West Seattle Bridge will detour to other Duwamish crossings.

Nickels, a West Seattle resident, served as mayor from 2002 to 2009, and said Mayor Jenny Durkan asked him to join the effort.

The group has 21 members, including neighborhood, maritime and small-business representatives, plus 10 “ex officio” members who are elected officials or staff. Meetings aren’t scheduled yet.

Meanwhile, the city formed a seven-member technical committee of engineers, which will sometimes exchange information with the citizen group.

Nickels said he expects the task force will continue until the city chooses a repair method, and then a replacement, for the 157-foot-high concrete bridge, which closed March 23.

“I do expect that the question of whether light rail should be part of the same structure, or not, is something we’ll have to deal with,” Nickels said. “Is there some advantage to being redundant, if there are separate structures?”

Some residents are curious about whether a shallow, immersed tunnel may work. Nickels calls himself “a bit of a skeptic” about trying heavy construction under the river, but said the group will listen to a range of ideas.

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