Image of a steel girder bridge in Fort Benton, MT, with a scenic view of the Missouri River Breaks

Bridge near Trout Creek, MT, that carries Blue Slide Road over Vermillion River.
Background scenic view of the Cabinet Mountains.

Manuals and Guidance

Please contact MDT's Load Rating Engineer for any questions, comments, or other feedback regarding current, interim or additional guidance.

Current Manual

Title Version Release Date Archived Versions
MDT Bridge Inspection and Rating Manual 1.1 October 2018

Interim Guidance

Title Version Release Date Archived Versions Revision to Current Manual Section
(if applicable)
Load Rating of Timber Bridges 1.1 12/11/2019 zipped file
(right-click and save file to computer)
New Bridge Asset Process 1.0 07/11/2019 n/a
Load Posting Procedures 1.0 02/03/2020 8.4

Additional Guidance

The following is intended to address frequently asked questions by communicating current MDT practices, and providing clarification or additional guidance until it is incorporated in interim guidance or manual update.

Load Rating

Department Memos

Bridge Memo 13-01, Safe Posting Load, Railroad Car Bridges
Bridge Memo 09-02, Concrete Deck, Assumed Sacrificial Wearing Surface and Concrete Strength