Ecological Impact of Hovercraft

Ecological Impact of Hovercraft Transportation in Alaska

Paul Valihura - Volpe National Transportation Systems Center
Stephen Petron - CH2MHILL

The United States Postal Service (USPS) has completed a 3-year demonstration program to transport bypass mail and non-priority mail by hovercraft on a year-round basis in the Yukon Delta of Alaska. The hovercraft would replace the current method of using fixed-wing airplanes for the transport of bypass and non-priority mail. The program involved Bethel and seven remote Alaskan villages along the Kuskokwim and Johnson Rivers. The USPS agreed to conduct waterfowl, fish, and subsistence monitoring to obtain data on actual impacts of the hovercraft project. The Alaska Hovercraft Ecological Monitoring Program evaluated the nature and extent of impacts, if any, from the use of the hovercraft to fish, waterfowl, and subsistence efforts. The intent was not to quantify the exact number of fish or birds that might be affected by the hovercraft. The EA/FONSI did not claim that no impact to these resources would occur, but instead concluded that negative impacts would not be significant. The monitoring was designed to provide information to support or refute the conclusion that there is no significant adverse impact to fish and bird resources and thus to subsistence efforts focused on those resources.

Little is known on the ecological impact of the hovercraft and less on the potential impact in the arctic environment. The paper is intended to show the methodology and results of the ecological monitoring conducted by the Volpe National Transportation Systems Center on this unique mode of marine transportation. Aerial monitoring during transect flights resulted in observing approximately 4,800 waterfowl. In boat reconnaissance and flushing response work, approximately 4,200 birds were observed. During observations for floating fish after the hovercraft passed, approximately 260 miles were observed directly behind the hovercraft and approximately 3,700 miles were observed along the hovercraft route. During the observation of potential impact to juvenile fish in shallow water, approximately 9,000 fish were counted during 87 seining. In the studies for identifying stranded fish when the hovercraft passed approximately 20,000 yards of beach were observed. In the studies for impact to subsistence, gill netting (110 sets) was performed. Blackfish (very little is known of these subsistence species) fishing success was observed in the winter. The importance of this information is to present scientific research to refute claims that the hovercraft could result in significant adverse impact to the natural environment as operated in the Yukon Delta National Wild Refuge. The result of the research provided the necessary information to allow the hovercraft to serve as an environmentally acceptable alternative mode of marine transportation in Alaska.