Optimization methods for arctic pipeline route selection

As arctic regions become more accessible for oil and gas exploration and development, the need for subsea export pipelines and flowlines will continue to grow. To reduce risks to the pipeline from hazards of natural or geologic origin, it is critical to consider a more sophisticated approach to route selection compared to traditional manual routing practices based on only the shortest length of pipe or connectivity to existing infrastructure. Arctic environments have unique geologic complexities compared to other types of subsea environments. It is important to identify and avoid or mitigate significant hazards such as ice gouges, strudel scours, or permafrost upheaval zones for subsea pipeline routes in arctic environments. In this paper, we demonstrate a workflow to identify and map multiple geohazards, incorporate pipeline-related criteria, classify and weight features based on their inferred risk to a subsea pipeline, develop a composite map of hazards, and perform GIS-based, leastcost pipeline routing techniques to produce the optimal pipeline route options. This approach has been used in deepwater and shallow water settings around the world. We will demonstrate the advantages of following this methodology using multibeam echosounder (MBES) bathymetry data from an arctic location to illustrate the approach for a hypothetical pipeline project in the early stages of development.