Driving Surface Aggregate (DSA)

Driving Surface Aggregate (DSA) is a well-graded, unbound mixture of aggregate designed for use as a wearing course on unpaved roads.  DSA is designed to achieve maximum density to resist erosion and traffic wear.  Properly installed DSA roads will have greatly reduced sediment loss and maintenance cycles.  DSA is the only approved surface aggregate for purchase in the Dirt and Gravel Road Program.  On May 10, 2016, the State Conservation Commission approved a new version of the DSA specification for use in the Program, see below.


Clearinghouse

DSA must be sampled and tested to insure it meets specifications before it is delivered to a project.  Districts can conduct testing themselves, or enlist the help of the Center.  If a District wishes to use the Center, please contact them as soon as a DSA supplier is chosen (at least 30 days before scheduled delivery.  The Center will act as a “DSA Clearinghouse” for DSA projects in an effort to improve the quality and consistency of Driving Surface Aggregate statewide.  Potential services from the Center include:

  • Visiting and talking with quarries to insure they understand the DSA requirements.

  • Collecting samples and performing testing to insure DSA meets all material requirements before delivery and placement.

  • Keeping records of aggregate testing to avoid duplicating efforts.

  • Establishing a central point of contact for quarries on DSA issues.

  • Assistance with contractor coordination.

  • On-site assistance during DSA placement.


Reference Documents


Webinars

May 19, 2016: DSA “Administrative” Overview

  • Overview of new SCC DSA spec, and what it means for CDs.
  • Webinar Link: The link to view the webinar. (~33 Minutes)
  • Presentation Downloads:

Other Aggregate Reference Documents