Backups of 15 miles on each direction of I-5 were reported in Lewis and Thurston County on Friday, after six cars and six trucks were involved in a collision that completely shut down I-5 northbound. The State Patrol says this got started at about 1:43 pm on Friday, in heavy traffic on I-5, just north of Centralia at milepost 84. A car driven by Olii Mihail of Vancouver changed lanes, clipping a pickup driven by Benjamin Alsterberg, 24, of Centrailia. That set off a chain reaction and pinball collision, eventually involving six passenger cars and six big rigs. Only three people reported minor injuries, and paramedics also had to deal with a woman in the backup who’d gone into labor. The freeway finally reopened at around 4:30 pm, but the traffic impacts lasted for hours after that, with bumper-to-bumper traffic on the freeway and gridlock in the city of Centralia. Troopers blame the crash on driver inattention, following too closely and an unsafe lane change. So far, no charges have been reported, as the crash investigation continues.