Box Elder Canyon – Bad Roads for RVs is on U.S. Highway 89/ U.S. Highway 91, east of Brigham City, Utah. It is steep and should be avoided in the winter. This is part of the descent from Sardine Summit.
Of course, you could say that RVs should avoid traveling in the winter in the Rocky Mountains and I would agree. It goes double for steep roads in the winter.
The beginning of the descent starts in Mantua getting steeper as the road turns to the west. The descent gets very steep and ends at Main Street in Brigham City.
In the summer, U.S. Highway 89/ U.S. Highway 91 is merely a steep road but I think you should know what you are getting into before you go there. Really the road is very nice, four lanes wide, and overall the grade alone isn’t a good enough reason to not travel on U.S. Highway 89/ U.S. Highway 91 east of Brigham City.
In the winter expect snow and ice. The road is maintained well but melting snow will run across the road and turn to ice nightly making for very hazardous driving.
Expect large vehicles to be traveling at slow speeds relative to traffic or speed limits.
See also our comments on the same road. Wellsville Canyon – Bad Roads for RVs
As for the Utah Department of Transportation, they have adopted twitter to get the most up-to-date road information to the public. They also have their own Apple and Android App. Tweets and App information is on this website. UDOT
Elevation: 5250 feet at the top – 4430 feet at the bottom.
Length: 2 miles – for the steepest section, near the bottom.
Terrain: 6% grades as the descent exits the narrow part of the canyon. The steepest areas are not at the top. Warning signs caution preceding the steepest sections.
Lanes: Four-lane highway
Turns: In the steep sections the turns are gentle.
Turnouts: The only turnout is the truck brake check area, on the right side, just past the exit to East 200 South.
Turnaround locations: None
Chain up areas: none clearly defined.
Restrictions: All vehicles more than 10,000 lbs must stop at the truck brake check area just past runaway truck area.
U.S. Highway 89/ U.S. Highway 91, east of Brigham City will occasionally close in the winter for deep snow. More likely than being closed, snowplows will continuously operate clearing the snow both night and day, when required.
Runaway truck ramps: One, well before the bottom of the canyon on the right side just past the exit to East 200 South deep gravel location not easily identified.
Caution: The end of the descent is at the stoplight for Main Street in Brigham City one mile past the mandatory truck brake check area.
Box Elder Canyon – Bad Roads for RVs, Our Experience
We traveled down Box Elder Canyon in our RV on September 29th, 2020. We also climbed Box Elder Canyon in our RV in 2018.
I would not hesitate to travel U.S. Highway 89/ U.S. Highway 91, Box Elder Canyon in our RV — in the summer. For us, it would be a normal travel day.
Here is our link to our interactive map. Bad Roads for RVs