A natural gas pipeline in the Arkansas River between Little Rock and North Little Rock ruptured, releasing 3.9 million cubic feet of natural gas, officials said.
A 2-mile section of the river ended up closed to traffic Tuesday as the company tried to determine what caused the 24-inch pipeline to leak and tries to fix it. A strong current in the river is making it difficult to inspect, said Phil West, spokesman for Houston-based Spectra Energy Corp.
The incident occurred either Sunday or Monday, officials said. “We are looking into it. We don’t know what caused it,” West said. The leak “most likely occurred during the weekend. We’re trying to figure that out.”
Information given to the Arkansas Public Service Commission indicates the leak occurred Monday and the cause is unknown, said John Bethel, executive director of the agency’s general staff.
He said the pipeline crosses the river near Bill and Hillary Clinton National Airport/Adams Field.
The pipe that leaked is a backup line that runs parallel to Spectra Energy’s main transmission pipeline. The main line, which also crosses under the river, runs from Texas to New Jersey. In Arkansas, the line provides natural gas to CenterPoint Energy, West said.
Valves on a 4½-mile segment of the backup pipeline closed before the leak occurred because it is not normally in operation, West said. The valves remained closed and there was no natural gas released Tuesday.
West said the leak did not leave any residual natural gas in the river and the released gas would bubble up and dissipate into the atmosphere.
“Just like any bubbles, natural gas would move up and out of the river quickly,” West said.
Chief Petty Officer Bobby Nash, 8th District spokesman for the U.S. Coast Guard, confirmed a stretch of the river closed Tuesday.
“We closed down the waterway so they can work on the potential source of the leak,” he said, adding that other parts of the river shut down because of flooding.
Spectra Energy’s dive team will use sonar and other tools to inspect the pipeline from the surface.
The company can also hire a team to repair the pipeline, but the Arkansas River is proving difficult, West said. “The current has been an issue for the dive crew,” he said.