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USCG proposes new port access routes Shipping routes through Chukchi Sea, Bering Strait and Bering Sea would avoid grounding accidents and reduce collision risks ALAN BAILEY Petroleum News
The U.S. Coast Guard has published its preliminary findings for the establishment of commercial shipping routes through the southern part of the Chukchi Sea, through the Bering Strait and across the Bering Sea. The idea is to improve marine safety by keeping vessels away from areas where shallow water and inaccurate charts pose vessel grounding risks, and where there is particular environmental sensitivity. And the proposed four-nautical-mile-wide, two-way route would provide adequate sea room to avoid vessel collisions while also providing vessels with flexibility in avoiding sea ice, the Coast Guard says in a report on its findings.
Increased shipping traffic in the region is causing concerns about the heightened risk of a shipping accident, with the potential for an oil spill that could cause environmental damage and impact subsistence hunting. But, given the international nature of the shipping, the Coast Guard anticipates pursuing its proposals through the International Maritime Organization. Meanwhile, the agency is inviting comments on its report.
Shipping patterns As part of its route study, the Coast Guard conducted a detailed analysis of shipping patterns in the region in recent years. The most common traffic has been ore carriers, 500 to 965 feet in length, carrying ore from the Red Dog Mine near Kivalina on the Alaska Chukchi Sea coast north of the Bering Strait. These vessels do not follow consistent routes in their passages from and to the south: In some cases they have come close to areas of heightened concern for subsistence harvesting, or they have transited areas where the water is not particularly deep and the charted depths are unreliable, the report says.
In 2012 and 2015 there was significant vessel traffic in conjunction with Shell’s Chukchi and Beaufort Sea oil exploration program. And there is frequent tug and barge traffic along the Alaska coast, delivering cargoes to coastal communities - this type of traffic is destination specific along the coast and would be unlikely to follow a prescribed route some distance offshore, the report says. There are fishing operations in the region, particularly in the southern Bering Sea.
Analysis of risks Because there have been relatively few marine accidents in the area of the Coast Guard study, the agency conducted an analysis over a broader region under U.S. jurisdiction, north of 50 degrees latitude and west of 155 degrees longitude. The agency found that the most common type of accident was grounding, with vessel complete loss of maneuverability also coming relatively high on the accident cause list. Vessel collisions were unusual.
The analysis of vessel movements, historic accident causes and current risks associated with commercial traffic led the Coast Guard to its proposed establishment of designated commercial shipping routes.
The Coast Guard considered several options for assuring the safety of shipping traffic, including options such as a regulated traffic separation scheme or a recommended route. The agency eventually determined that the best arrangement for addressing the various risks is a defined two-way route, supplemented by avoidance areas, areas where there is the particular potential for the disruption of subsistence activities and where the pollution risk is particularly high.
Preferred alternative The Coast Guard’s preferred alternative is the establishment of a two-way route extending north-south through the Bering Strait south to Unimak Channel, an opening in the Aleutians through to the North Pacific. This main route would pass east of St. Lawrence Island. However, another route component would branch to the southwest, from a point on the north-south route south of the Bering Strait. This branch would pass between St. Lawrence Island and the Russian mainland. The long north-south route would flex its way around areas of shallow water or environmental sensitivity - because the curvature of the Earth would impact navigation over such a long distance, the inflections in the route would be marked by defined waypoints, the Coast Guard says.
An alternative route possibility would be to just have the north-south route and not to have that branch to the southwest off the Russian coast. And yet another alternative is to cut off the southern end of the north-south route, ending the route at a point in the Bering Sea where the tracks of vessels bound for Unimak Pass and Dutch Harbor tend to merge.
There would be four avoidance areas: one in a near central section of the Bering Strait; one around King Island, to the southwest of the Seward Peninsula; one around and extending south of St. Lawrence Island; and one around Nunivak Island, southwest of the Yukon-Kuskokwim Delta.
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