Are we ready to construct submarine pipelines in the Arctic?
Authors: Palmer Andrew 
Published: October 2008

Submarine pipelines in the Arctic seas have been under consideration for more than 25 years, but almost none have been built. One reason for this is that petroleum prices have not increased as fast as had been expected, but another is that there have turned out to be several technical difficulties, among them ice gouging, subgouge deformation, strudel scour, marine permafrost, leak detection and possible repair. The environmental movement remains resistant to Arctic petroleum development offshore, and has a substantial influence on regulatory approvals. Forward movement must be predicated on a complete and convincing resolution of technical questions.

This paper examines each problem area, and sets out to reach a judgement on the question that have been resolved and how far the industry is ready to construct Arctic pipelines offshore.

Introduction

Twenty-five years ago, the hydrocarbon resources of the Arctic offshore seemed on the point of rapid and energetic development. Many schemes were promoted, some of them very ambitious. None of them got off the ground, partly because costs and technical uncertainty made the economics seem questionable. The promoters were doubtless grateful for that when hydrocarbon prices collapsed ten years later. Nevertheless, much research was carried out, and a very few projects were actually carried through, among them the Bent Horn oil export system and the Panarctic Drake F-76 flowline bundle demonstration project. Afterwards some research continued, often against a background of declining budgets, and some ideas changed markedly. The delay can be seemed as a much extended parallel to the delay that occurred in the construction of the Alaskan land pipeline.

The oil price has recovered, at least for the moment, and some Arctic projects appear economically and technically feasible. They are receiving renewed interest, both in the North American Arctic and the Russian Arctic, though there are still technical questions and environmental opposition. Most of these projects involve marine pipelines. The objective of this paper is to review the state of knowledge, and to attempt to assess how far the pipeline industry is now ready for the new challenge.

It is clear that some projects are very much more demanding than others. Rightly and unsurprisingly, all the indications are that the industry will begin with the less ambitious and less difficult projects, and expects to apply the lessons learned to the larger projects that may be reached later, probably not for ten or twenty years. This paper should not be interpreted as a comment on any specific project.

As in the case of deep water, some pipeline construction problems are the same in the Arctic as they are elsewhere, and some are easier in the Arctic. Pipeline lateral stability, for example, is rarely a major constraint, because pipelines will have to be trenched - which enormously enhances stabilityand wave action is generally limited.

Ice gouging and subgouge deformation

The problem is well-known. Large masses of ice drift around, and are pushed by ice sheets and by pack ice, in turn driven by wind and current.