Temporary Erosion and Sediment Control Manual
The Temporary Erosion and Sediment Control Manual (TESCM) replaces Chapter 6 and Appendix 6A of the Washington State Department of Transportation (WSDOT) Highway Runoff Manual. It outlines WSDOT’s policies for meeting the National Pollutant Discharge Elimination System (NPDES) Construction Stormwater General Permit requirements and the requirements in Volume II of the stormwater management manuals published by the Washington State Department of Ecology.
The TESCM is intended for use during the design, permitting, and construction phases of transportation construction projects. It covers:
- TESC plan design and implementation
- TESC BMP application and installation
- SPCC plans
- Discharge sampling and reporting
- Site management and documentation
- Compliance-related issues
1,557 work zone-related crashes
were recorded on state highways in 2025.
542 people were injured
in 2025 due to work zone-related crashes.
29% increase in fatality collisions
in work zones from 2024 to 2025.