The massive Whiteside County fire was reported around 11:15 p.m. Monday after residents heard a blast, said Scott Melton, the assistant fire chief in the community of Erie. No one was injured, but the towering flames could be seen for miles.
The pipeline was carrying a mixture of ethane and propane, Melton said.
Authorities evacuated about 80 families living within a mile radius of the fire and shut down some nearby roads. By Tuesday morning all but two families were allowed to return to their homes. The remaining families were being kept away as a precaution, he said.
Melton said workers with the pipeline owner, Houston-based Enterprise Products Partners, were able to remotely turn off a valve to limit the gas flow to the site and that crews were investigating what caused the fire.
"It's not much of a fire now, but there's still some fuel left in the pipe and they're going to let that burn off, because it's the safest way to handle it," he said.
A message was left with an Enterprise spokesman before business hours Tuesday.
Erie is about 27 miles northeast of Davenport, Iowa.