A valve on a military fuel line broke Wednesday, spilling about 100 gallons of diesel oil onto Balboa Avenue near Mt. Abernathy Avenue, fire officials said.
Sand was placed around the spill to prevent it from spreading and traffic was routed around the area, fire officials said.
They said the pipeline sends oil from Miramar Naval Air Station to Point Loma. There have been no other problems with the pipeline, they said.
Firefighters responded to the incident about 2:50 p.m. and the Navy shut down the line at 3:30 p.m.
The leaking fuel filled a manhole before spilling onto the street.
Fire Department spokesman Robert Drake said chances of the oil contaminating water supplies are minimal.