Clients: Various Members of the Petroleum Industry

Arctic production pipelines convey oil and gas from offshore islands to the shore. The pipelines are buried in the seabed to protect them from forces imposed by ice, waves, currents, and strudel scouring forces. The pipelines are installed through a slot in the late-winter ice sheet. Specialized amphibious wide-track backhoes excavate the subsea trench. The trench is backfilled following the pipeline installation. Coastal Frontiers has developed methods to guide the efficient installation of subsea pipelines, including the following tasks:

Arctic Subsea Pipeline Installation

  • Monitor the depth of the initial trench bottom and note progressive infilling from side wall sloughing

  • Provide approval to lower the pipeline into the trench once natural sloughing has subsided and trench bottom elevation has stabilized

  • Organize on-site radio communication between water level and pipeline surveyors and the pipeline installation contractor to allow timely approval for laying in the pipeline

  • Oversee placement of gravel plugs or gravel-filled bags to improve pipeline stability

  • Develop instrumentation to measure the flatness and elevation of the trench bottom and roll of the pipeline as it is installed

  • Monitor the elevation of the trench backfill at the conclusion of installation

  • Note the formation of ice gouges and strudel scours on or near the pipeline using aerial overflights and summertime bathymetric surveys