On a splendid summer morning, it was a particularly grim combination of events: a truck crashing at a key traffic pinch point at the start of rush hour, killing the driver, spilling debris across both sides of the Lowry Hill tunnel, shutting down a busy urban interstate for half a workday.

The accident at the westbound entrance to the Minneapolis tunnel killed Glen Johnson, 62, of Colfax, Wis., driver of the truck. Three vehicles coming upon the wreckage moments after the crash either struck or were hit by debris, but those cars' occupants were uninjured, said State Patrol Lt. Eric Roeske.

"The fact that someone lost their life is certainly tragic, but this had the potential to be much worse, given the amount of traffic in that location," Roeske said.

The cause of the accident hadn't been determined Wednesday. An investigation is continuing.

The westbound semitrailer-truck hit a light pole and crashed shortly after 6:20 a.m., the State Patrol said. The truck's tractor, separated from the trailer, flipped and slid into the tunnel, killing the driver. The truck's cargo of automotive parts spilled into the eastbound lanes.

Westbound lanes reopened shortly after morning rush hour, and eastbound traffic resumed flowing shortly before noon.

George Hall of Woodbury was heading to work on westbound I-94 toward the tunnel shortly after 7 a.m. He said the wreck added "a good 40 minutes" to his daily commute to his Minneapolis job because only one of three lanes was open.

Amanda Gibson, 25, of Roseville said she'd been leaving early for her job in Golden Valley this summer to avoid construction-related delays.

On Wednesday, she drove into stopped traffic on westbound I-94 about 2 miles east of the tunnel just after 7 a.m., crawled along for 30 minutes and traveled only about a mile to the 11th Avenue exit, which allowed her to get to I-394 and on to Golden Valley, where she arrived for work more than an hour late.

Roeske said there are crashes every now and then in the Lowry tunnel, but the "scope of this one is quite a bit larger."

A stretch of I-94 about three-fourths of a mile to the east continues to be the most crash-prone piece of highway in Minnesota, although the tunnel itself is not. Westbound traffic approaching the tunnel brings together traffic that has merged from northbound Interstate 35W, from further east on I-94 and from downtown Minneapolis freeway entrances, as well as traffic trying to exit to Hennepin and Lyndale Avenues.

The tunnel is not a high-crash location because traffic in both directions is usually congested and slow by the time it reaches the entrances, said John Hourdos, a professor of civil engineering and director of the Minnesota Traffic Observatory at the University of Minnesota.

And Hourdos said accident numbers in the higher-crash area have fallen by one-third in recent years, after lines that reduced abrupt merging were painted on the road, he said.

Disruption to Metro Transit bus service after the crash was minimal, said spokesman John Siqveland.

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