Enbridge Inc. was given approval late Wednesday to restart an unharmed 30-inch diameter natural gas pipeline that is in the same right-of-way as a 36-inch pipeline that exploded in British Columbia (BC) on Tuesday.

Repair crews had scrambled Wednesday to fix damage done to the pipeline in the right-of-way for BC’s main natural gas conduit that ruptured and exploded. The mishap shut down both of the Westcoast Transmission system pipes. The unharmed 30-inch diameter line had stopped flowing as a precaution.

The restart approval by the National Energy Board “follows a comprehensive integrity assessment that evaluated a number of potential impacts,” the company said. “Enbridge looked for evidence of damage to the pipe, geotechnical and ground disturbance, and other potential integrity issues on the 30-inch line.”

With the 30-inch line deemed fit for service, “our restart plan is to gradually bring the line’s pressure up to approximately 80% of normal operating capacity. Once this process is safely completed, some much need capacity will be restored for our customers.”

The Westcoast system had gas in the majority of its network south of the accident site in sparsely populated northern BC near the industrial town of Prince George.

Enbridge thanked emergency responders, civic and government officials and others for their response effort. It said it also appreciated the Lheidli T’enneh First Nation “for their patience and cooperative engagement, and are committed to continue to work together moving forward.”

Distributor FortisBC had urged its one million customers to conserve gas in case the supply interruption stretches out to be long. Distribution companies in the northwestern United States that use BC gas exports posted similar warnings. Puget Sound Energy (PSE) in Washington state indicated it would be switching its electric generation to alternative fuels rather than natural gas.

The Bellevue, WA-based utility asked customers to conserve gas and electricity following the pipeline rupture, which “could affect PSE’s ability to supply natural gas to our customers’ homes and businesses. Although our gas supply has been impacted, there is no damage to the PSE gas system or safety hazard to our customers from the pipeline failure in Canada.”

Spot natural gas prices in the region surged higher on Wednesday for Thursday delivery. Malin next-day gas shot up 36 cents to $3.345, with volumes increasing more than 200,000 MMBtu day/day. Kingsgate surged 36 cents to $3.16, with volumes slipping 4,000 MMBtu day/day. Westcoast Station 2 in Canada, meanwhile, plunged more than C$1 to C92 cents/GJ, while volumes tumbled some 334,000 MMBtu day/day.

The cut to supplies lifted pricing points in other producing regions as well. In the Rockies, Transwestern San Juan jumped 51 cents to $2.91, and points along the El Paso Natural Gas system shot up more than 40 cents to average in the low to mid-$2.80s.

The mishap ignited a flurry of speculation on both sides of the border that motor gasoline prices would rise steeply if oil refineries were forced to make deep production cuts by a prolonged disruption of natural gas fuel for their heat processes.