Stahly Engineering provides transportation engineering services for projects ranging from pedestrian trails to major highway design. Experienced staff manages projects from initial planning to final inspection. We assist our public clients with identification of funding sources and funding applications, provide comprehensive survey and design services, and work in partnership with clients and contractors to ensure a well-built final project.


Stahly Engineering has an impressive list of projects completed for the Montana Department of Transportation ranging from design/build projects for rest areas on the Interstate system to comprehensive, multi-million dollar highway design projects including a section of the Highway 93 redesign. Additionally, our firm works extensively with Montana Counties, serving as their road and bridge engineer, with long term contracts that prove our commitment to building solid relationships through excellent customer service and quality projects.


Private developers benefit from Stahly Engineering’s talent for transportation design and ability to help guide projects through the regulatory process with City, County, and State government entities.  

Historic Marysville Road Reconstruction

This 6.8 mile road reconstruction project is located in Lewis & Clark County on Marysville Road, approximately 15 miles northwest of Helena in a rural area, in mountainous terrain, providing access to the town of Marysville, public lands, and the Great Divide Ski area.  Marysville Road is classified as a non-NHS secondary rural minor collector but is not on the State Secondary System. 


The project scope included an environmental review process that Resulted in a “Finding of No Significant Impact”. Design included improved horizontal and vertical alignments, gabion structures, drainage improvements, guardrail, asphalt surfacing, signing and striping, and rechannelling the existing streambed. 


Construction administration of the project was taken over by Lewis and Clark County. Stahly Engineering assisted them with administration and inspection activities.


Wetland mitigation was required for the project. This was accomplished through a crediting scheme that moved wetlands to the Lewis and Clark Fairgrounds site within the same watershed.

Lewis and Clark County Forest Highways

Stahly Engineering successfully assisted Lewis and Clark County with applications to the Federal Highways Administration (FHWA) for funding to provide surface preservation and safety upgrades for Sun River Road and Benchmark Road - Forest Highways within the County.


Safety Project

Our project team worked very closely with County & FHWA personnel in the initial project application, preliminary design (PE), and construction inspection/administration (CE) for safety improvements that included redesign of curves and signing.


Surface Preservation – Overlay Benchmark and Sun River Roads

Design and construction inspection was provided by the Stahly Engineering Team for an asphalt overlay of existing hard surface portions of Benchmark and Sun River Road. Design challenges included failed/weak pavement areas that required detailed  digouts and crack sealing expansion during overlay operations.


Surface Preservation – Gravel Improvements to Benchmark and Sun River Roads

Engineering project management, design, and construction inspection provided by Stahly Engineering to grade, shape, compact, and place new gravel and magnesium chloride on 14.4 miles of Benchmark Road and 5.4 miles of Sun River Road.

Fergus County Crystal Lake Road Graveling and Chip Sealing

Crystal Lake Road is the only access to Crystal Lake, a busy public recreation destination. The existing roadway was very rough and surface aggregate sparse. The project consisted of applying a six inch section of crushed top surfacing to approximately nine miles of roadway.  Significant improvements were made to drainage and safety. Stahly coordinated County crew roadway grading and shaping prior to contractor graveling. 

B Street Road and Sidewalk Improvements

Stahly Engineering has provided streetscape assistance for two projects in the City of Livingston. In 2012 engineering design and construction improvements were completed on B Street. Tasks generally included survey, design, construction administration and fulltime inspection.  

Trail, Sidewalk, and Pedestrian Bridge Projects

Pedestrian and bicycle trails enhance community living in a variety of ways by providing safe facilities for alternative modes of transportation and access to the great outdoors. Stahly Engineering provides design and construction administration for public and private trails including those funded through MDT’s Transportation Alternatives (TA) program and its predecessor, the Community Transportation Enhancement Program (CTEP). Projects include:


  • Downtown Helena 400 Block Streetscape

  • Gallatin Gateway Trail

  • Montana Heritage Trail

  • Big Sky Trail

  • Gallatin River East Trail

  • Manhattan Sidewalks and Downtown Streetscapes

  • Three Forks Milwaukee Park

  • Three Forks Pedestrian Bridge

  • Browning School Path

  • Big Horn County Fairgrounds Trail Loop

  • East Helena Schools Safe Routes to School Trail

  • MDT Lyndale Avenue Path and Pedestrian Tunnel

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