Yellowstone National Park officials are proposing an earlier opening date and later closure at the East Entrance for snowmobiles and snow coaches.
The gate, located west of Cody, Wyoming, would be open from Dec. 15 to March 15, the same as the park's two other winter gates.
The change could add an average of 19 to 25 additional snowmobiles in the park each day during the winter season.
The other two winter gates are the West Entrance, near West Yellowstone, and the South Entrance near Jackson, Wyoming. Access to the park at the North Entrance near Mammoth Hot Springs, Wyoming, is also regulated for over-snow travel to the park's interior. However, the entrance is also the only one open to automobiles year-round, allowing travelers to drive to Cooke City through Lamar Valley and past the Northeast Entrance.
Over-snow travel has been limited by the park since the implementation of a winter-use plan in 2013. The plan in part requires snowmobilers to be with guides. Members of the public can pass a test to be certified to guide their own group. They must also enter a drawing in August for a date to enter the park, because daily entrance and group size is capped.
Each day during the winter season the East Entrance is allocated two commercially guided snowmobile trips, one non-commercially guided trip, and one commercial snowcoach.
Under the park's plan, the maximum number of snowmobiles allowed in the park from all entrances in a day is 480.
The existing seasonal closures of December 15-21 and March 2-15 were originally implemented due to avalanche safety concerns on Sylvan Pass, which climbs to more than 8,500 feet in elevation. The Park Service performs avalanche control at the pass by using a howitzer firing 105mm shells to blast snow from Avalanche and Hoyt peaks.
"With many years of implementation, the NPS now has the operational capacity and expertise to safely open the pass on December 15 and to keep it open until March 15," the agency said in a press release. "This change will standardize opening and closing dates for the entire park."
In 2007, the Park Service considered closing the East Entrance because it sees less use in the winter. That idea was dropped after protests from Cody businesspeople.
In addition to the extended season at the east gate, the Park Service is proposing to change the daily opening time for the South Entrance from 7 a.m. to 8 a.m.
"The current opening time means that contract holders/operators leave Jackson, Wyoming, well before sunrise, and before road conditions can be properly assessed and hazards mitigated by NPS staff," the press release said.
Comments are being taken on the proposed changes through Oct. 29 and may be submitted online at: https://parkplanning.nps.gov/winteruseAM or by mail. Comments will not be accepted by fax, email, or other means. Mail comments to: Compliance Office, Attention: Winter Use Adaptive Management, P.O. Box 168, Yellowstone National Park, WY 82190.
The park's Winter Use Management plan can be found at: https://www.nps.gov/yell/learn/management/winter-use-management.htm.