Add rain to metro Atlanta traffic, and you can expect to be in your car for a while. Throw in a wreck involving a tanker truck, and your foot may not leave the brake pedal for a while.

That was the case Monday morning when a tanker truck hauling about 9,000 pounds of propane overturned against the median wall while traveling northbound on I-75 in Cobb County.

Investigators believe one vehicle hydroplaned and hit the median, setting off a chain reaction involving another car and two 18-wheelers, Officer David Baldwin with Marietta police told the AJC.

After colliding with another tractor-trailer, the tanker truck tipped over, Baldwin said.

None of the propane leaked, but the threat of a major spill concerned emergency responders, who worked throughout the day preparing to upright the tanker. Two lanes of I-75 northbound and one southbound lane were closed throughout the day.

Only one minor injury was reported, but it was a painful day to be traveling in the area.

Shortly after 4 p.m., emergency responders were forced to shut down all lanes of I-75, just south of I-575, Baldwin said.

The interstate re-opened about 30 minutes later. But it was too late to avoid a messy evening commute, which was halted before it began in full force.

Traffic backed up in both directions, but was especially bad for those heading into the northern suburbs. Gridlock on I-75 also caused traffic pile-ups on Cobb Parkway as many commuters sought an alternative route, according to the WSB Radio traffic center.

The driver that caused the wreck was cited, Baldwin said.