Petrojarl Banff Suffers Second Mooring Failure Since 2011

Recent sources report that on January 3, the Teekay-operated, 20,000 dwt FPSO Petrojarl Banff lost two of ten permanent mooring lines securing it at its position at Canadian Natural Resources' Banff field in the North Sea. Production has been suspended. No spills or casualties were reported and her crew of 44 remains on board.

The field had been back online for only a year and a half, following a three year gap caused by the loss of five of ten anchors in 2011. Nearby, Maersk Oil's Gryphon Alpha lost four of ten moorings in a similar incident early the same year, resulting in billions of dollars expense in repairs.

A Canadian Natural Resources spokesperson told media January 8 that “the Petrojarl Banff remains in position under its own power.”

“CNR and vessel owner Teekay will establish the exact nature of the situation once both anchor lines are secured and a visual survey has been completed . . . The FPSO is currently secure and is being assisted with station keeping by the anchor handling vessel Normand Ranger . . . anchor handling vessel Island Vanguard is also on site,” she added.

Neither firm has issued a public statement regarding the incident as of January 8.

Mooring failures are not an uncommon problem for floating offshore facilities, industry analysts say. In a 2013 paper, Kai-Tung Ma of Chevron said that between 2001 and 2011, there were 21 offshore mooring failures, over two per year, and that nearly half were multiple-line failures. KBR subsidiary Granherne listed 23 mooring failures from 2000 to 2013, four resulting in riser failure and extended field shut-down. The firm added that an estimated 150 mooring lines were repaired or replaced during that time.

“We are having too many [repeated] mooring failures,” Ma told Offshore Engineer. “In 2011, we had four and when preparing this paper, there were another two chain failures and one wire rope failure, so it is ongoing.” And consequences can be high, he added. “Nan Hai Fa Xian [moored south east of Hong Kong] had four of eight lines broken . . . Plant [equipment] was flipped upside down, pipe ruptured and all the risers broken.” He added that multiple failure modes make prediction and prevention a challenge for operators.

The January 3 Banff incident is the fourth disruption in offshore development reported due to recent rough weather in the North Sea.

As of January 6, the Prosafe flotel Safe Bristolia was holding position on its emergency anchor following a parted tow line some 65 nautical miles east of Scotland, but bad weather continued to interfere with efforts to resume the tow. The BP Valhall platform had to be evacuated in late December after a runaway barge threatened a collision; ConocoPhillips also pulled crew from rigs in the area. And two were injured and one killed when a heavy wave hit the semi-submersible COSL Innovator as it was under way. The Innovator had already been taken off of its station in the Troll field offshore Norway to lower the risk of an accident from Storm Frank.