A handful of innovative up-grades will improve safety and winter travel through Provo Canyon.
US-189 through Provo Canyon is part of a Scenic Byway that follows the Provo River, crosses the Uinta National Forest and provides access to Sundance Resort, Timpanogos National Monument, and the Deer Creek Reservoir. The steep, winding road requires drivers to use caution year around. But during winter, Mother Nature ups the ante; deep canyon walls, weather conditions, and the Provo River make clearing ice and snow a challenge.
Sun angle is much lower in the winter, explains UDOT Meteorologist Scott Patterson. “The canyon is so steep that some sections of the road will see little if any sunlight to help melt the snow and ice.” And the Provo River running along the road adds moisture that can lead to frost on these shaded sections of the road. Due to the orientation of the canyon, “in southwest winds, heavy snow can fall in the canyon” while nearby areas see much less snowfall.
A look at three years of crash data averages comparing the road to statewide crash averages shows that Provo Canyon’s conditions are atypical in Utah. Contributing factors for crashes are more likely to include conditions related to weather and visibility. “Drivers in Provo Canyon need to realize that this is a unique place…you can’t treat it like an average roadway,” says Scott Jones, UDOT Safety Programs Engineer.
UDOT works hard to make all roads as safe as possible. As new technologies become available, UDOT can make changes and improvements. Some new road features and equipment in Provo Canyon will enhance safety year around and improve winter snow and ice removal. “We have a big bag of effective new tools and we’re pulling out the right ones out for this location,” says Lynn Bernhard, Maintenance Methods Engineer for UDOT.
Rebounding delineators survive vehicle hits: Delineators are devices with retroreflectors that give guidance to drivers at night and when visibility is low. Pole mounted delineators help drivers see the edge of the road when snow is deep. Provo Canyon will have a new type of pole mounted delineator that’s designed to rebound after a vehicle hit. The delineators stay in service longer and require fewer repairs – good news for motorists and UDOT crews.
Collapsible, easy to fix crash cushions: Attenuators, sometimes called crash cushions, are placed on fixed structures or gore areas on freeways to minimize injuries to motorists, absorb kinetic energy during a crash, redirect automobiles in a path parallel to the attenuator and minimize property damage to vehicles and the roadway. Most attenuators are one-hit wonders; they do their job well but need extensive repair or full replacement after a crash.
Attenuators with a very smart new design have been installed in Provo Canyon. The system is made of separate connected chambers that collapse when hit head on. When hit from the side, damage is limited to the impacted sections. A hydraulic cylinder inside the chambers absorbs the crash. Repair is simple; maintenance workers simply re-expand and re-bolt the attenuator sections or replace the damaged sections.
“Two quarter-inch bolts and it’s back in service,” says UDOT Station Supervisor Neil Lundell. He estimates that repairs will usually take about an hour. The cost for repairing the new crash cushions is much less – from thousands of dollars to hundreds per crash when a section of the system needs to be replaced. When just the bolts need to be replaced, cost per crash is about .25.
Simple to switch triple-blade plow: Three culprits of winter road calamity – snow, slush and ice – each require a different plow blade. Provo Canyon’s weather system delivers spotty conditions along the roadway. In the past, plow operators had to go back to the maintenance station to switch blades. A new triple blade plow will let operators switch among blades while on the road.
The triple blade plow was developed by the Clear Roads organization, a group of public and private entities that study ways to maintain mobility and safety during the winter months. The triple blade plow is a non-propriety design that any manufacturer can produce.
An under-road system to combat winter frost: A de-icing system will be installed where moisture from the river causes frost to form. Sensors embedded under the pavement trigger the release of de-icing liquid before ice forms on the road. Many high mountain bridge decks have de-icing systems, but this pavement segment is the first road to get the special help.
A new solution for pre-wetting: Lundell says his crew will use “a different cocktail,” for wetting the road before a storm. The brine solution has ingredients that freeze at a lower temperature and help prevent ice from forming.
Safe driving in Provo Canyon
All together, the changes will help preserve mobility and safety. Motorists also need to do their part by driving safely. Jones stresses that “drivers need to be actively engaged in driving” not just in Provo Canyon, but on all roadways.
Lundell sees many crashes that happen when motorists drive too fast for conditions and the crash data above backs up his observations. Even when message boards warn drivers “they still just keep going too fast.” He urges motorists to always use caution. “Just because the snow is off, don’t speed up.”