Transportation Engineering

As one of our most established service areas, our transportation engineers, designers, and technicians deliver unmatched expertise, quality, and innovation to support all sizes of transportation projects. We provide comprehensive bridge engineering, bridge safety inspection, highway engineering, traffic planning and engineering, and construction inspection services. From traffic studies to major interstate improvements, from small bridges and culverts to expansive bridge structures, we are committed to finding solutions that meet each project’s unique budget and timeline. We are well versed in the management necessary for design and inspection contracts for clients from state departments of transportation, departments of natural resources, counties, and other local municipalities. Our dedicated transportation experts have hundreds of years of combined experience supporting projects of all sizes.

Bridge Engineering

LDG’s bridge engineers and designers have been connecting communities with award-winning bridge replacements, new constructions, and rehabilitation projects since 1989. Our experienced team offers a range of services in bridge engineering (including design for small to medium span bridge structures, pedestrian, railroad, equestrian, and aqueduct projects), bridge and covered bridge rehabilitations, and bridge bundling projects. We typically complete 100% of the project with the same design team including the roadway plans, cross sections, hydraulics and permitting, traffic control plans, right-of-way plans and erosion/sediment pollution control plans. This unique structure helps ensure a streamlined and high-quality product.

  • Design-Build
  • Grade separation structures
  • Bridge rehabilitation/widening
  • Covered bridge rehabilitation
  • Complex structures
  • Historic structure preservation
  • Viaducts & aqueducts
  • Drainage structures
  • Railroad structures
  • Constructability & construction engineering
  • Geotechnical
  • Flood control structures

Bridge Safety Inspection & Maintenance

We have broad expertise in completing bridge safety, overhead sign, and retaining wall inspections for private entities, local municipalities and state departments of transportation. Since 1989, LDG-certified bridge safety inspectors (CBSIs) have inspected more than 8,000 bridge structures and 1,700 overhead sign structures and completed more than 900 load rating analyses. Our experienced team skillfully navigates the required coordination, field inspections, report completion, maintenance considerations and communication for every inspection with each individual client. We can assist clients not only with emergency bridge repairs/strengthening, but also long-term bridge maintenance plans to preserve their structures for years to come. We also provide in-house unmanned aircraft system (UAS) technology to supplement inspections, allowing us to identify, record and document bridge inspection topics in a manner that is less disruptive than traditional methods.

  • Bridge safety inspection
  • Overhead sign safety inspection
  • Retaining wall inspection
  • Drone inspection
  • Bridge load rating analysis
  • Permit load rating analysis
  • Bridge conditionassessments
  • Bridge strengthening/retrofits
  • Bridge cost estimating
  • Comprehensive bridge maintenance plans
  • Bridge vehicular damage assessments
  • Flood inspections and damage assessments

Highway Engineering

LDG’s highway engineering legacy is paved with successful projects of all sizes, from interstates to rural roads. Our success is fueled by our ability to provide innovative solutions for all aspects of highway design while focusing on the client’s objectives, minimizing costs, and meeting schedules. We understand there is often more than one alternative and that construction costs must be weighed against potential benefits. Our ability to deliver full project support from alternative alignment studies through final design and construction inspection/consultation helps us uncover efficiencies and cost-savings opportunities throughout the process. Our design process follows the strict requirements of LDG’s QA/QC policy, which ensures constructible projects of the highest quality.

  • Interchanges/Intersections/Ramps
  • Interstate
  • Roundabouts
  • Hydraulics & hydrology
  • Erosion & sedimentation plans
  • Permitting
  • County/Municipal/Private Roadways
  • Welcome centers
  • Park & ride
  • Transit-oriented development

Traffic Planning & Engineering

Larson Design Group offers experience encompassing all phases of traffic engineering and planning services to support the diverse needs of our clients. Our services include data collection, signs/signals/markings, zoning, land use planning/impacts, long-range transportation plans, capacity and safety analysis, a variety of specialty studies, and much more. LDG is an industry leader travel demand forecasting and traffic simulation modeling. We provide state-of-the-art transportation analysis techniques to address challenging issues. Expert staff is fluent in software packages for modeling work including VISSIM, VISUM, TransCAD, SimTraffic, Corsim, Cube Voyager, TP+, and Tranpan.

  • Travel demand modeling, forecasting
  • Traffic simulation modeling
  • Signal & lighting design
  • Smart transportation design
  • Origin-destination studies
  • Long-range planning
  • Corridor analysis
  • Intersection design
  • Traffic studies (T.I.S., modeling)
  • Right-of-way plans
  • Traffic calming
  • Special use lanes
  • Bicycle/pedestrian trails and facilities
  • Streetscapes
  • Complex intersection operational analysis
  • Multimodal simulation
  • Transit signal priority
  • Toll plaza operations
  • 2D & 3D visualization
  • H&H analysis and reports
  • Highway feasibility
  • Deficiency studies
  • Permitting
  • MPO/RPO planning services

Construction Management/Construction Inspection

LDGs cadre of certified construction services staff is dedicated to representing your interests at the construction site. Through a variety of services such as materials testing, schedule coordination, change order management, project documentation, ensuring the work is being performed according to the plans, applicable codes, and specifications, and verifying invoices for payment, we help to ensure the project is completed on time and within budget.

News & Insights
News & Insights
Accolades: ASHE Pittsburgh Awards ‘Outstanding Project’ to LDG-led McLaughlin Roundabout Project
Transportation Planning Podcast
LDG and Union County Officials Rededicate Historic Covered Bridge

Accolades: ASHE Pittsburgh Awards ‘Outstanding Project’ to LDG-led McLaughlin Roundabout Project Through Accolades, LDG shares news of the awards, rankings, and professional achieveme...

LDG’s Planning Team has boots on the ground on projects around the country. On this episode of the LDG Podcast, hear Lauren Carlson (Transportation) and Ashleen Starr (GIS) talk about...

MIFFLINBURG, PA – This week, a rededication and ribbon cutting ceremony was held for Union County Bridge No.