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Montana has over 70,000 miles of roads in cities, counties and highway districts. Montana LTAP's focus is on assisting state and county road offices and city street departments in road and bridge maintenance and repair. We also provide worker safety training courses such as flagger certification, traffic control supervisor certification, and forklift certification. By sharing technical information and improving the distribution of this information, the program promotes efficient use of local transportation agencies' scarce resources.

The LTAP program is financially supported by the Federal Highway Administration (FHWA), Montana Gas Tax, (HB359), Montana Department of Transportation (MDT), and Montana State University, (MSU-Bozeman). Any opinions, findings, conclusions, or recommendations presented in this homepage do not necessarily reflect the views of FHWA, MDT, or MSU-Bozeman.


Bridge Posting Notice

Bridge Load Program Image road with weight limit sign

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The Montana Department of Transportation (MDT) recently issued a new load postings for the US 87 Elk Creek Bridge, between Grass Range (5 miles SE) and Roundup in Fergus County and Old Hwy 87 Two Leggins Canal Bridge, one mile west of Hardin in Big Horn County. The posting is part of a multi-year effort to update load ratings and postings Montana bridges as mandated by the Federal Highway Administration (FHWA). 

The FHWA mandate is in response to changes in the trucking industry over the last decade. Truck manufacturers are building specialized hauling vehicles (SHVs) capable of legally carrying heavier loads than typical vehicles have in the past. SHVs are single-unit, short-wheelbase, multiple-axle trucks commonly used in the construction, waste management, bulk cargo, and commodities hauling industries. Often one or more axles can be raised or lowered as needed to comply with statutory weight limitations. 

These SHV configurations concentrate heavy loads over a short length. They have been found to overstress bridges beyond what was previously modeled by standard commercial vehicles. To account for their increasing presence and ensure safe operation, FHWA has determined that all states must include these new, short, heavy vehicles when evaluating the safe limits of bridge capacity. 

To comply with the mandate, MDT is currently updating load ratings for 4,500 public bridges across the state, including approximately 2,500 owned and maintained by MDT. This effort is expected to take about four years to complete.  

Bridge weight restrictions are required when the engineering analysis of a bridge, known as a load rating, indicates that it cannot carry standard, legal loads. Load ratings provide information about how much distributed weight can safely pass over a bridge. Load posting signs show maximum weight limits for different vehicle types, depending on their axle configuration. A posted bridge is safe to use, but the weight of certain vehicles must be limited accordingly. 

Further information on understanding and interpreting Montana’s weight limit signs and silhouettes can be found in MDT’s load posting brochure, located here: http://bit.ly/mtbridgebrochure

To assist with public outreach and education about the bridge load posting program, MDT has created an interactive map with statewide load posted bridge locations available here: http://bit.ly/mtbridgemap. This map will allow you to map an appropriate route for your vehicle.

For the most up-to-date information and additional resources, visit MDT’s Bridge Load Posting Program website at http://bit.ly/bridgeload.

For questions about the program or specific bridges, please call the project hotline at 1-888-824-8445, or email [email protected].

The MDT Bridge Bureau is available to meet if you would like to learn more about this bridge posting or the load posting program. Please email Aly Russell at [email protected] or call her at 406-223-5058 if you are interested in a virtual meeting or phone call to learn more.


Curve Signing: Proper Chevron Spacing

Many of our practitioners are not taught what horizontal curve geometry is, or how to understand the plans given to them by engineers. We often see terms like PC, PT, PI and other assorted curve data terminology that may or may not be relevant to the task at hand.

In the videos below, developed by the FHWA resource Center with Montana LTAP, Montana’s LTAP Director Matt Ulberg uses available online tools to evaluate a curve’s radius, and includes the simple analogy of a pizza box to relate the data engineers use in plans to the physical locations of curve points on the ground.  He also shows how to use the available digital measurement tools in the office in order to properly layout W1-8 Chevron Signs in the field. 



Montana LTAP office is housed in the Transportation and Systems Engineering Building on the south side of Montana State University campus.

Please use our PO Box address for US Postal Service mail:

Montana LTAP PO Box 173910, Bozeman, MT 59717**

Use our physical address for FedEx, UPS or other carriers:

Montana LTAP 2327 University Way, Suite 230, Bozeman, MT 59715**

**Please note the different zip codes. It is important to use the correct address or mail will be returned to sender.