318 AUTHORIZATION

A 318 Authorization may be required for construction or construction-related activity in state water that could cause short-term or temporary turbidity.

AGENCY: Montana Department of Environmental Quality (DEQ)

  • WHO NEEDS A 318 AUTHORIZATION?

    A 318 Authorization applies to public or private applicants planning construction activity in state water that will cause unavoidable short-term violations of water quality standards for turbidity.

    If the project also requires a 310 Permit or SPA 124 Permit, the 318 requirement may be addressed during that review process.

    See Examples of 318 Authorization Projects →

HOW TO APPLY FOR A 318 AUTHORIZATION

  • BEFORE YOU START:

    See what information, photos, plans and project details may be helpful to have ready. You can start your application and return anytime.


    Prepare Before You Apply →

  • 1. COMPLETE THE JOINT APPLICATION FORM IN GILLY


    Create an account and begin your application.

    Gilly guides you through the project information and any additional questions required for the permit.

  • 2. FOLLOW THE 318 SUBMISSION REQUIREMENTS

    If you are applying directly for a 318 Authorization, download your completed Joint Application Form from Gilly. Submit your completed Joint Application Form and required fee through DEQ's current application process.

    If your project also requires a 310 Permit or SPA 124 Permit, the 318 requirement may be addressed during that review process.

    318 Authorizations are not submitted through Gilly.

    Learn More About 318 Authorization →

318 AUTHORIZATION PROJECT EXAMPLES MAY INCLUDE:

  • STREAM & BANK PROJECTS

    • Bank stabilization

    • Stream restoration

    • Other work that temporarily increases sediment or turbidity

  • CROSSINGS & INFRASTRUCTURE

    • Culvert installation, replacement or repair

    • Stream crossings

    • Other construction within the stream channel

  • IN-STREAM CONSTRUCTION

    • Excavation or grading in state water

    • Temporary construction activity that increases sediment or turbidity