Highway maintenance - Winter operations & extreme events

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Winter operations & extreme events

Snow and ice plans

WSDOT crews start working long before snowflakes fall to keep roads open during inclement weather. The agency uses advanced weather forecasting to predict where snow and ice will accumulate and use the information to pre-treat high traffic corridors. The anti-icing chemicals used by WSDOT help prevent frost and ice from bonding to the pavement. Once snow has started falling and accumulating, crews switch to a salt pre-wet with a corrosion-inhibited liquid deicer that helps snow and ice to melt, making it easier to remove with snowplows—but it takes time to work.

Avalanche control

WSDOT's Avalanche Forecasting and Control team is a dedicated crew of experienced professionals who monitor the weather and snow to determine when avalanches may occur. The crew is split into two regional teams with full-time employees and seasonal employees. The Avalanche Control Supervisor for each team leads the crew throughout the year.

When conditions indicate an avalanche is imminent, teams employ various methods and tools to bring down unstable snow in a controlled manner. The team works throughout the fall, winter, and spring along Washington's mountain highways.

Performance Analysis


WSDOT looks to shore up shortages and gaps

WSDOT faces the challenge to deliver a resilient and resourceful maintenance program that has become exacerbated by the national and global supply chain shortages and material gaps for many commodities.

These shortages and gaps make it difficult for the Transportation Equipment Fund program (TEF) to locate repair parts, tools, shop equipment, vehicles, and heavy equipment. The program has been innovative to meet the fleet's needs and every effort is being made to keep the fleet operational and replace equipment innovatively. New equipment brands are being introduced into the TEF fleet and contracts have been made with a more diverse vendor base. In the end, the solutions enacted by WSDOT to overcome the global supply chain issues have led to a more resilient TEF fleet.


Tow plows tackle double duties

WSDOT's Eastern Region is home to the agency's three tow plows. These plows are designed to be towed and extended out at an angle behind a plow truck to clear a secondary lane at the same time. Tow plows, when angled, have a 14-foot clearing path.

These plows are also equipped with a granular spreader and liquid tanks to apply deicing materials. The combination of the tow plow with the materials application allows a single truck to perform the work of two trucks, clearing two lanes at once. Tow plows not only clear the roadway faster, but also reduce the cost of the operations.

The three tow plows in Eastern Region have nicknames as part of a public engagement campaign. This light-hearted campaign has yielded serious results—including increased public engagement about WSDOT's plowing work and extending the reach of plow safety messaging to a broader audience.

The plows are named:

  • Plowie McPlow Plow
  • The Big Leplowski
  • Sir Plows-a-Lot

Naming each tow plow has become a tradition of sorts, with the agency allowing the public to submit suggestions each time a new tow plow is added. Staff then narrow it down to a smaller list before putting the name up to a vote on social media.

WSDOT faces ongoing struggle to meet maintenance staffing needs

WSDOT is working to rebound from a hiring freeze that accompanied Initiative 976 as well as continued retirements, recruitment/retention struggles and COVID-19 restrictions that furthered staffing shortages while increasing training time for new employees.

Pandemic-related revenue decreases that left WSDOT unable to hire in 2020 continued into July 2021. Recruitment efforts increased at that time but were affected by the mandatory vaccine requirement for state employees, which resulted in the loss of trained personnel both in Maintenance and the Transportation Equipment Fund (motor pool and mechanics).

WSDOT continues to recruit for vacancies created by various factors, including an aging workforce and several pandemic-related circumstances including: furloughs, hiring freezes, temporary instead of permanent hires, vaccine mandates, and increased competition for workers with diesel mechanic qualifications or commercial driver licenses (CDL).

The CDL issue, is partly due to a pandemic-related spike in the demand for CDL truck drivers, which affected all states in 2021. As a result, WSDOT aligned workload expectations with available staffing levels. While it shifted resources wherever possible, it also could not push its crews beyond safe workloads.

Staffing levels affect WSDOT's statewide winter operations

With the pandemic affecting winter operations for the second year in a row, WSDOT's winter operations staff was down 19.5% from approximately 1,500 to roughly 1,200. Maintenance was already down 142 positions as of October 1, 2021.

After the October 18, 2021 vaccination mandate, another 151 staff in those positions resigned or retired from the agency, leaving a total of 293 winter operations positions unfilled—more than four times what it was the year prior.

Maintenance responds to extreme events statewide

WSDOT's planned maintenance activities come to a halt when an emergency or disaster occurs because crews must first respond to potential hazards that threaten Washington's transportation infrastructure. These types of emergency responses divert maintenance crews from scheduled work as they must assist with road closures and traffic control and, in some cases, begin initial repairs. These unfunded emergencies exacerbate the maintenance backlog because they take personnel away from planned activities.

The summer of 2021 marked a historic heat wave that affected the state's infrastructure and roads, causing pavement damage across the state. During the late-June and early-July heat wave, regions across the state experienced multiple days at well above 100 degrees Fahrenheit which resulted in buckling and peeling pavement. WSDOT crews responded to 26 extreme heat-related issues across the state.

Landslides, washouts, and cleanup due to heavy rains and previous fire damage also affected Washington's roadways in 2021, including long-term closures in some locations. In total, WSDOT crews responded to 41 landslides.

US 101 south of Forks landslide due to November storm

A large landslide closed US 101 at milepost 185 near Forks after a storm on November 15, 2021. The slide affected approximately 50 feet of roadway while three smaller embankment failures filled a ditch with debris and trees, clogging a nearby culvert and causing water to spill onto the roadway. Maintenance crews were able to clear downed trees, debris and water, and install a jersey barrier in the center of the roadway to reopen access to Forks. Crews restored one-way, alternating travel near Kallman Road on Wednesday, November 17 after two days of work. An emergency contract is being prepared for a long-term fix of the site. Smaller slides on SR 113 and SR 110 were cleared in the days that followed.

US 101 at milepost 185 near Forks in mid-November image
This landslide closed US 101 at milepost 185 near Forks in mid-November.


COVID-19 impacts on 2020-21 winter service

While safety remains the agency's top priority during the COVID-19 pandemic, the heightened need to be strategic with both overtime hours and materials may mean that roads and passes are closed more frequently during large storms, and that those closures may last longer.
Tire chains may also be required more often as reduced crews may be able to keep roads open but not completely clear of snow or ice. Lower priority roads might also go untreated for longer periods of time while available crews focus on high priority, more heavily traveled routes. For the safety of crews and travelers, roads that cannot be maintained will be closed until the weather situation resolved.


WSDOT Maintenance rises to the challenge to help state through historic 2019 winter

Snowstorms in February and March 2019 produced several daily and month-long records. WSDOT maintenance crews were on non-stop, 12-hour shifts for extended periods in efforts to keep people and goods moving safely. Dangerous, drifting snow in central and eastern Washington continued into March, swamping vehicles and forcing road closures. Some roads faced issues with drifting snow almost as soon as they were plowed.

Western Washington experienced below-normal temperatures and repeated snowfall in elevations above 500 feet, resulting in increased costs as WSDOT crews dealt with snow and ice. Eastern Washington had extremely low temperatures well into March and repeated snowstorms coupled with high winds. Adverse weather resulted in numerous road closures, in addition to much higher snow and ice removal costs than anticipated.

Notable statistics from the 2019 winter include:

  • Statewide average temperatures for February were 9.6 degrees colder than normal
  • Seattle experienced its largest February snowfall in 70 years (20.2 inches compared to the typical snowfall of 1.7 inches)
  • Snoqualmie Pass set a 10-year record for snowfall in 24 hours (31.5 inches), and had 68 inches in 72 hours.
  • Spokane experienced its second snowiest February on record (30 inches compared to the typical snowfall of 6.8 inches)


WSDOT manages avalanches to improve safety on mountain passes

WSDOT employs two avalanche control teams; one team on Snoqualmie Pass and one on Stevens Pass. The teams make it possible to maintain these mountain passes in the winter and are key to opening Chinook and Washington passes in the spring.

WSDOT's experienced professionals carefully monitor weather and snow conditions to manage avalanche risks to state highways. Teams employ a number of techniques, including explosives, hand charges, bomb trams (a cable pulley that carries explosives into position) and surplus military artillery. The teams also make recommendations on other mitigation techniques such as diversion berms and fences.

The teams play a significant role in assisting maintenance crews in working avalanche danger zones through the use of avalanche beacons, safety protocols and annual training.


NA not doing Comment out during GNB 88

There were 565 traffic fatalities on all Washington state public roads in 2017. This is a 5.4% increase from the 536 fatalities recorded in 2016. The number of traffic fatalities has increased 8.4% in the 10 years since 2008, when there were 521. While annual traffic fatalities declined each year between 2008 and 2013, recent years have seen increases. The fatalities count for 2017 was 29.6% higher than its 10-year low of 436 in 2013.

The number of annual serious traffic injuries increased slightly (0.3%) from 2,217 in 2016 to 2,224 in 2017. Serious traffic injuries in Washington have decreased 12.9% since the count of 2,552 in 2008, but are 16.1% higher than their 10-year low of 1,916 in 2013.

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