Dubuque, Iowa — A collision between a semi-truck and a passenger vehicle early Tuesday morning, March 31, 2026, caused a major diesel fuel spill at the intersection of Dodge Street (Highway 20) and the Northwest Arterial.

The crash occurred around 4:58 a.m. and damaged the driver’s side saddle tank of the semi, releasing its entire contents of diesel fuel across the roadway. 

Dubuque Fire Department, Dubuque Police Department, and Dubuque County Sheriff’s Department responded to the scene. Occupants of the passenger vehicle and the semi-truck driver suffered minor injuries and were transported to local hospitals for treatment.

Hazmat 1 crews from the Dubuque Fire Department, assisted by Dubuque Public Works, handled the cleanup. The Iowa Department of Natural Resources was notified due to potential environmental concerns from the spill. The intersection remained closed for several hours during containment and cleanup efforts. 

No fires or serious injuries were reported. The exact volume of diesel spilled was not immediately released, though saddle tanks on semi-trucks typically hold hundreds of gallons.

Authorities have not disclosed details on the cause of the crash or fault. The incident disrupted early morning traffic in a key Dubuque corridor.

This event underscores the challenges of hazmat responses in urban areas, where fuel spills can create slip hazards, environmental risks to nearby waterways like the Mississippi River watershed, and significant traffic impacts even in pre-dawn hours.

The intersection was expected to reopen once cleanup was complete and safety confirmed. Updates on the investigation may come from local police or the Iowa DNR in the coming days.

For real-time road conditions in the Dubuque area, check local traffic alerts or the City of Dubuque website.

The Intersection was back opened at 7:00 AM.