At a deep bore tunnel discussion last night hosted by The Stranger, Mayor Mike McGinn announced that beginning next week, a city-hired consultant will study how to best mitigate the estimated 40,000 car trips a day that will be funneled onto downtown Seattle streets once the state's deep-bore tunnel is built.

"We know we’re not going to make the streets bigger," said McGinn, "so where do the cars go?" He answered this by saying that the city's next step should be to "do the work in the [state's study] that WSDOT isn't doing," which includes looking at surface transit options to help divert the thousands of cars trips that will be pushed onto city streets. Essentially, McGinn is laying the groundwork for a surface transit option Environmental Impact Study (EIS)—a popular tunnel alternative that was never officially completed. "We need to develop options so that people have alternative routes—alternatives to I-5 under the convention center or light rail to West Seattle," he said.

Seattle City Council Member Mike O'Brien, the only council member to participate in last night's Town Hall talk, which attracted over 200 people, echoed the mayor's traffic concerns: "[The state's study] assumes that there will be no tolling [on the tunnel], but the traffic modeling is done on the assumption that there will be tolling," O'Brien said. With tolls in place,“Two-thirds of traffic isn’t going to go through the tunnel. There's no plan to mitigate this... It is really disturbing."

While the mayor explores his surface options, a group called Move Seattle Smarter is gearing up to protect the city from cost overruns once the tunnel project moves forward. On December 8, the group will file an initiative to "establish a strong and enforceable policy that will protect us from cost overruns," according to Drew Paxton, the group's spokesman. Paxton says one of the groups goals is establishing a cost accountability commission to monitor the tunnel's costs.

But as the group's initiative only addresses the issue of tunnel cost overruns, it wouldn't prevent the state from wading knee-deep into a project that still doesn't have secure financing. This pressing issue—as well as the city's real concerns surrounding traffic mitigation and cost overruns—haven't been fully addressed by state officials and other ardent tunnel supporters, who all declined attending last night's public talk.