UPDATED (Friday, 12 a.m.)—U.S. Route 1 is open to traffic in both directions at the Conowingo Dam, about 24 hours after it was first closed, Maryland State Police told Patch.

A tractor trailer hauling fuel overturned and caught fire on the Cecil County side of the Conowingo Dam around 11 p.m., Wednesday, as first reported by Patch.

The dam carries U.S. Route 1 over the Susquehanna River.

While it was closed, Patch advisted travelers looking to cross the river in Thursday's evening rush to consider using Interstate 95 over the Tydings Bridge, or U.S. Route 40 over the Hatem Bridge.

The Conowingo Dam is the only toll-free span across the Susquehanna south of the Mason-Dixon line.

Tolls on both the Hatem and Tydings bridges will increase Tuesday per new toll rates.

According to Harford County Fire and EMS spokesman Rich Gardiner, a medevac helicopter was en route to the area shortly before 11:30 p.m., Wednesday to transport one patient. Emergency radio communications indicated that as much as 3,000 gallons of fuel was spilled, but Gardiner said he did not know how much fuel the truck was carrying.

WBAL reported that approximately 7,500 gallons of fuel spilled onto Route 1.

Darlington Volunteer Fire Company, Lancaster (PA) County Fire and the Harford County Hazmat team assisted county fire personnel with the incident.