Aggregate Source Approval
Notice: Temporary Impact to Materials Evaluation Program
WSDOT’s accounting system upgrade will result in a temporary pause on establishing new reimbursable agreements for material evaluations from March 31 through April 15. While applications will continue to be accepted, new evaluation and testing work cannot begin until work orders are established after April 15. Some processing delays may continue briefly during system stabilization. Early submittal of anticipated applications is strongly encouraged.
Search our database containing detailed information about companies that provide aggregate for road projects. Find instructions for submitting your aggregate for approval.
Aggregate Source Approval (ASA) database
Search the ASA database for the source(s) that meet your selection criteria. From the resulting list, choose which one you want to examine in greater detail. ASA Testing may take up to 90 days due to heavy workloads.
ASA map
Use the ASA map to manage and tracks aggregate sources in Washington.
- Locate sources on the map using the query tab or by manually searching, using latitude and longitude.
- Select the source and follow the link to that source’s on-line Aggregate Source Approval report.
Use the 'Information' tab for instructions on Navigation Tools, Coordinate Locator, Layer Controls, Attribute Table Display and Information Tools.
Submitting aggregate for approval
To initiate the submittal process, contact the ASA Engineer at ASA.
Use the WSDOT Recognized Concrete Aggregate Testing Facilities for 1 year ASR (ASTM C1293) (PDF 17KB) to locate a testing facility near you.
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.