I80 westbound was completely closed Thursday evening as the Utah Highway Patrol, Park City Fire District and Summit County emergency services responded to the rollover.
The driver was transported by Airmed helicopter to a hospital in Salt Lake City. His passenger, a co-driver who was in the sleeping compartment, was not injured, and no other cars were involved.
One lane of the interstate opened up around 7 p.m. and the second lane opened at midnight.
Lt. Randall Richey with the Utah Highway Patrol said the driver’s injuries were very serious but were not expected to be life threatening. The truck did spill its own diesel fuel, and Richey said it was fortunate the tank was only a quarter full. Park City Fire District spokesperson Michelle Andersen said city and county crews worked quickly to contain that.
Richey said a witness, another truck driver who was heading west behind the truck that rolled over, estimated the semi’s speed to be around 60 miles per hour.
Further investigation will try to determine exactly what occurred, but Richey said on that part of I80, speed is usually a factor.
“Preliminarily, I would say probably a speed that's a little too fast for the curve that he was going into," Richey said. "And typically what we find and these not always but typically it's it is some version of driver error or whether it's a little bit of an inattention and then they get into the curve and realize how tight the curve is and, and with truck that large and a load that sits up high like that and the high center of gravity. Sometimes if you're carrying a little too much speed into the curve, just a little jerk or the wheel can, can be enough to cause that top of that trailer to start to tip.”
The speed limit on that portion of I80 is 65 miles per hour for cars and 55 for tractor trailers. Advisories are posted on curves suggesting drivers reduce speed to 45 or 50 depending on the particular curve.
The Utah Department of Transportation is responsible for setting those speed limits. Richey said safe speeds depend on vehicle size and design, their loads and centers of gravity, and road conditions. He added that UDOT regularly assesses speed limits and also utilizes warnings like reflective arrows.
He agreed that the area presents a problem.
“The trouble with Silver Creek Canyon is that there's so many curves it's not like one curve one set of curves like eco junction is we will get semi truck rollovers in in that canyon more often than we'd like, obviously, but they don't always occur in the same spot," he said. "We've gotten them at pretty much every curve along the way. Hopefully that there's an engineering fix that can help and maybe there's an enforcement piece that we need to look at as well.”
Thursday’s crash occurred two miles west of a very similar accident two weeks earlier, in which a semi truck traveling west rolled over at the Tollgate Canyon exit and spilled organic peroxide onto the ground and into a storm drain that flows into Silver Creek.
Organic peroxide a is a hazardous raw chemical used to make various products including hand sanitizer. Silver Creek and a 100-yeard section of the Rail Trail in that area were closed while the county environmental health team worked with contractors to remove contaminated water and soil.