Ship’s pipe-laying gear damaged by high winds off Nova Scotia

The world’s first pipeline-laying ship equipped with dynamic positioning was blown off course in 68-mph winds off Nova Scotia, prompting the operators to change a safety policy.

The 600-foot Lorelay’s pipe-laying equipment was damaged when stiff winds pushed the vessel a quarter-mile out of position Oct. 16, 2009. The ship, owned by Allseas Group SA of Switzerland, was installing the 107-mile-long natural gas pipeline on the Atlantic Ocean floor for EnCana Corp.’s Deep Panuke project about 155 miles southeast of Halifax, Nova Scotia.

EnCana spokeswoman Lori MacLean told Professional Mariner that weather conditions were more severe than predicted. Lorelay could not maintain its heading and started to move off position.

“A decision was made to cut the abandonment and retrieval cable from the winch because the cable was attached to the pipeline on the seabed,†she said. “Once the cable was cut, the Lorelay recovered its position and rode out the weather.â€

Debbie Mountenay, manager of administration and industrial benefits at the Canada-Nova Scotia Offshore Petroleum Board, said the ship itself was not damaged. There was some damage to the stinger, the extension at the stern which supports the pipe to be laid on the sea floor.

No one was injured. A follow-up survey conducted soon afterwards indicated the pipeline was not damaged, MacLean added. The pipeline was pulled about 1,312 feet from its original position, she said.

Previously named Natalie Bolten, Lorelay was built by Flender, Lübeck-Siems in Germany in 1974 as bulk carrier. It was shortened and converted to a pipe layer in 1986.

Allseas Group said Lorelay was the world’s first pipeline-laying ship with dynamic positioning, representing a new generation. It is equipped with Kongsberg Simrad 521 and 11 dynamic positioning systems. The vessel is equipped with one pipe transfer crane of 35,000 pounds capacity at 108 feet and one heave-compensated mast crane with a capacity of 661,000 pounds at 46 feet. Lorelay can accommodate 216 crewmembers.

Allseas didn’t respond to a request for comment on the incident.

The EnCana pipe-laying project was active in the summer and fall of 2009. It involved the installation of facilities required to produce and process natural gas from Deep Panuke. EnCana said the natural gas will be processed offshore and transported, via sub-sea pipeline, to Goldboro, Nova Scotia, for further transport to market via the Maritimes & Northeast Pipeline. First gas is expected from Deep Panuke in 2010.

Lorelay returned to the field Oct. 27 following repairs to the stinger and a thorough safety inspection.

At the direction of the Canada-Nova Scotia Offshore Petroleum Board, a new safety practice was developed in response to the Lorelay incident. For the duration of the Deep Panuke pipe-laying program, if severe weather was encountered, MacLean said the boat would not remain attached to the pipeline, but would disconnect from it completely until the weather cleared. The pipe would then be retrieved.

Pipe-laying was completed on Oct. 30. Lorelay departed Nova Scotia waters soon after. The trenching of the pipeline continued with the Allseas trenching vessel Calamity Jane.

Michel Drouin

By Professional Mariner Staff