Incident response - Blocking & extraordinary incidents
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Incident Response measures showing blocking & extraordinary incidents
Blocking & extraordinary incidents
Incidents blocking highways cause negative impact on economy, safety and commute time. Keeping track of blocking or non-blocking incidents is important to increase highway performance. Blocking incidents are incidents that obstruct at least one lane of travel. WSDOT tracks these incidents as they have a greater impact on incident-induced delay. Non-blocking incidents occur on the shoulder or off the roadway altogether. They have less effect on traffic, but frequently result in traffic delays due to drivers being distracted and slowing down while passing the incident. Extraordinary incidents take six hours or more to clear. They have huge impact on commute, safety and economy.
Source: Washington Incident Tracking System.
Note: WSDOT's Incident Response management program indicates incidents took six hours or more to clear as extraordinary incidents. For more detail on
WSDOT Incident Response Phase 3 research method (PDF 5.9MB).
Multi-year trends
Between 2018 and 2022, the percentage of incidents that blocked the roadway ranged from 26.3% to 30.5% of all the incidents to which IR teams responded. During this five-year period the number of extraordinary incidents was between 28 to 42 annually out of which, approximately one-third involved commercial vehicles such as semi-trucks.
Annual highlights
In 2022, 30.5% of the incidents WSDOT's IR teams responded to blocked at least one lane of traffic. Blocking incidents caused 68.1% of the incident-related congestion costs for 2022. Among all blocking incidents for the year, 40 took more than six hours to clear with 17 of these involving commercial vehicles.
In 2021, 32.2% of the incidents WSDOT's IR teams responded to blocked at least one lane of traffic. Blocking incidents caused 68.3% of the incident-related congestion costs for 2021. Among all blocking incidents for the year, 36 took more than six hours to clear with eight of these involving commercial vehicles.
In 2020, 29.1% of the incidents WSDOT's IR teams responded to blocked at least one lane of traffic. Blocking incidents caused 63.7% of the incident-related congestion costs for 2020. Among all blocking incidents for the year, 28 took more than six hours to clear with 10 of these involving commercial vehicles.
In 2019, 25.3% of the incidents WSDOT's IR teams responded to blocked at least one lane of traffic. Blocking incidents caused 61.5% of the incident-related congestion costs for 2019. Among all blocking incidents for the year, 41 took more than six hours to clear with 15 of these involving commercial vehicles.
In 2018, 26.3% of the incidents WSDOT's IR teams responded to blocked at least one lane of traffic. Blocking incidents caused 64.1% of the incident-related congestion costs for 2018. Among all blocking incidents for the year, 42 took more than six hours to clear with 15 of these involving commercial vehicles.