HUNTSVILLE — The Top of Utah’s two alpine highways are set to close Wednesday.
State Road 65, the Big Mountain Highway, and S.R. 39, the Monte Cristo Highway, will close for the winter at 9 p.m., Nov. 21.
The Monte Cristo Highway will close between milepost 37, just east of Huntsville near Ant Flat Road, and milepost 56 near Woodruff in Rich County.
The Big Mountain Highway will close between milepost 3, north of the Emigration Canyon turn-off in eastern Salt Lake County, and milepost 13, which is about two miles south of the East Canyon State Park in Morgan County.
UDOT Region One spokesman Vic Saunders said the routes, which are subject to extremely heavy snowfall at a moment’s notice, will remain out of service until spring.
Saunders said the cost of winter maintenance and motorist safety concerns make the roads essentially impossible to keep open from late November through May.
During the closures, motorists who would use the Monte Cristo Highway to pass the Monte Cristo summit should use either U.S. 89 through Logan Canyon, or a combination of Utah S.R. 16, Wyoming S.R. 89, Interstate 80 and Interstate 84 to access communities east and west of the highway.
Motorists who normally use The Big Mountain Highway should use I-84 and S.R. 66 from Morgan, or S.R. 65 from Interstate 84 at Henefer to access the East Canyon recreation area.
When open, the heavily traveled mountain passes are often used by outdoor recreation enthusiasts.
The state once considered keeping both roads open through the whole year, but a 2014 study found that costs associated with staff salaries, equipment, materials, fuel and roadway improvements outweighed potential benefits like travel time savings, community connections, recreational property access, safety and potential tax gains from development opportunities.
While the roads are generally open by mid-spring, sometimes heavy snow forces the state to keep them closed longer. In 2011, the Monte Cristo Highway didn’t open until mid-July as extremely high snow levels remained throughout a cool spring. That year, off-highway snow depths reached 25 feet in some locations.