• WSDOT pavement lane miles in fair or better condition worsened 2.0 percentage points from 92.0% in 2021 to 90.0% in 2022
  • Remaining Service Life of state-owned pavement decreased 4.0 percentage points in 2022, to 43.5%, compared to 47.5% in 2021
  • Statewide in 2022, 7,938 (43.1%) of the total 18,420 pavement lane miles on state-owned highways were due or past due for a preservation project

Preservation of the state highway system pavement is like maintenance on a vehicle. The best and most long-lasting vehicles have been serviced regularly, had repairs taken care of on time, and received immediate attention when there is an issue. Pavement is the same in that it lasts longest when preservation projects are performed on time. Preservation can be deferred, but like a vehicle, once it is deferred, the repair costs increase with time.

WSDOT has delayed pavement preservation on some highway sections for over a decade. Statewide, its preservation backlog (also known as Deferred Preservation Liability) decreased 12.2% from $524 million in 2021 to $460 million in 2022, but was 9.5% (approximately $40 million) higher than it was five years ago in 2018.


  • WSDOT pavement lane miles in fair or better condition worsened from 93.0% in 2020 to 92.0% in 2021 (chip seal roadways were included in 2021)
  • WSDOT's pavement Deferred Preservation Liability increased 9.6% from $478 million in 2020 to $524 million in 2021
  • WSDOT estimates it will need up to $112 million annually over the next 24 years for concrete preservation


  • WSDOT pavement lane miles in fair or better condition increased slightly from 92.9% in 2019 to 93.0% in 2020, not including chip seal roadways
  • COVID-19 restrictions limited WSDOT's data collection for pavement condition to 20%. In a typical year, the agency collects 100% of this data
  • WSDOT is not preserving enough pavement to replenish what was used in 2020, repair needs continue to grow

COVID-19 limits WSDOT pavement data collection

WSDOT usually collects pavement condition data for 100% of the state-owned route system. Due to COVID-19 restrictions, WSDOT could only obtain 2020 data for approximately 20% of the lane-miles. The agency's pavement data collection vehicle requires a driver and an operator to safely collect the data, but for a time WSDOT personnel were not allowed in the van within six feet of each other due to COVID-19 safety measures. Most of the data collection was for Washington's interstates—which accounts for approximately 40% of the annual vehicle-miles traveled. Chip seal projects were also not included in 2020 pavement data due to COVID-19 restrictions.


  • WSDOT expects to stop preserving pavement on ramps, roads with speed limits below 45 mph, and projected funding levels
  • WSDOT pavement lane miles in fair or better condition improved from 91.4% in 2018 to 93.2% in 2019 due to the completion of several the inclusion of chip seal pavement condition data
  • Washington is expected to meet NHS pavement condition in 2022, but miss them by 2028


  • WSDOT pavement lane miles in fair or better condition declined for the fourth year in a row, going from 91.8% in 2017 to 91.4% in 2018
  • Washington is expected to meet federally mandated MAP-21 targets for NHS pavement condition in 2022, but miss them by 2028
  • WSDOT estimates it will need up to $88 million annually over the next 30 years for concrete preservation
  • WSDOT plans to stop its chip seal conversion program in 2021 due to funding constraints

Pavement background

WSDOT ensures interstate pavement preservation takes priority over other roadways due to the Federal Highway Administration's Transportation Performance Management requirements. The emphasis on these more-traveled strategic freight corridors (also known as T-1 and T-2 corridors) can have larger effects on increases and decreases in the percentage of VMT-weighted pavement in fair or better condition.

During the last 15 years, WSDOT's approach to pavement preservation has focused on extending how long its pavement assets remain in fair or better condition. WSDOT has stretched every dollar available, applying crack sealant and patching potholes and converting lower volume asphalt pavements to chip seal (Bituminous Surface Treatment). However, due to chronic underfunding for decades, this strategy is no longer sustainable.

Pavement management is the practice of applying the right amount of money to the right pavement at the right time. When funding isn't available, projects that are needed are not programmed, and roadways are kept serviceable by maintenance practices such as pothole repair, crack sealing and patching. These are temporary fixes that are not meant to serve as long-term solutions. Roads with many patches have numerous openings for water to seep into the pavement structure and cause deeper failures. Every preservation project that is delayed becomes a more expensive rehabilitation project in the future.

Strategic freight corridor classifications

WSDOT classifies highway segments, or corridors, by how much freight travels on them. T-1 freight corridors are the most heavily traveled and see over 10 million tons of truck freight per year. Corridors that see between four million and 10 million tons of truck freight annually are T-2 corridors and corridors that see between 300,000, and four million tons of truck freight annually are T-3 corridors. Both T-1 and T-2 corridors are considered strategic freight corridors under the definition established in RCW 47.06A.020.

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