One lane of southbound I-25 remains closed after a fuel tanker crashed into a guardrail and rolled, causing a major diesel spill Saturday morning in Douglas County.

The driver, a 32-year-old man from Firestone, was traveling south on I-25 when he ran onto the right shoulder, overcorrected and ran off the right side of the road, State Patrol spokesperson Gabriel Moltrer said.

The truck collided with a guardrail and rolled an unknown number of times before coming to rest in a ditch off the shoulder of the highway, Moltrer said. The cab of the truck landed on its wheels, and the tanker trailer landed on its side, leaking into the ditch.

State troopers responded at 2:26 a.m., Moltrer said.

The tanker truck was the only vehicle involved in the crash that shut down I-25 between exit 188 for Castle Pines Parkway and exit 187 for Happy Canyon Road, Moltrer said.

As of 2:50 p.m., the left three lanes of southbound I-25 had reopened, according to the Colorado Department of Transportation. The right-most lane remained closed for continued clean-up.

Northbound I-25 was not affected.

About 50 South Metro Fire Rescue workers responded, including a hazardous materials team, according to the department.

When fire crews arrived, they found an overturned semi with major damage — including a crushed cabin, warped metal and leaking fuel tank, according to a video released by South Metro Fire Rescue Saturday.

The driver suffered serious injuries and was taken to a hospital, South Metro Fire Rescue announced on X.

About 2,500 gallons of diesel fuel spilled from the tanker, which has a 9,000-gallon capacity, South Metro said in the release. South Metro previously reported an 8,000 gallon tank.

Firefighters dug five dams in the ditch where the truck turned over to stop the fuel from spreading while the hazmat team drilled holes into the tanker to pump out the rest of the fuel and transfer it to another truck, the release stated.

Once the fuel is completely offloaded from the original tanker, the truck can be pulled out and towed away, South Metro stated in the release.

Evacuations were considered but weren’t necessary.

Ambipar Environmental Services arrived at sunrise and worked with the Hazmat team to pump the spilled fuel into oil drums, according to South Metro.

This story will be updated.

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