Top Civil Engineering Firms in the USA

AECOM: A Century of Flood Control Mastery

If there is a company that has shaped American civil engineering for over a century, it would be none other than AECOM. For such a long period, this firm has been delivering some of the country’s biggest flood control programs. AECOM holds the number one ranking for dams and reservoirs from Engineering News-Record.

Its team provided civil engineering quality assurance on Florida’s Herbert Hoover Dike, a 143-mile system shielding communities from hurricane-driven flooding. AECOM also built the 2,700-foot Olmsted Dam, logging 13 million construction man-hours. In hurricane-prone states, this firm’s flood resilience expertise ensures the safety of entire regions.

Capabilities:

• Dams, levees, and flood risk management
• Ports, marine, and navigation channels
• Bridges and large-scale water infrastructure

Sectors Serving:

• Federal and state governments
• Coastal and floodplain communities
• Ports and defense agencies

Cad Crowd: Civil Talent Without the Overhead

Not every organization on this list functions like a traditional engineering design office, and Cad Crowd is proof of that. The firm provides a platform that connects AEC companies with vetted civil engineers, drafters, and CAD designers across the United States.

With Cad Crowd, clients tap into topography plans, bridge plans, roadway designs, and drainage systems on demand. This flexible model is exactly what firms facing sudden capacity gaps or tight deadlines need. For companies dealing with shifting state permitting codes, this countrywide network of Cad Crowd offers adaptable, project-specific expertise.

Capabilities:

• Roadway and topography design
• Bridge plans and drainage systems
• 3D scale models and BIM services

Sectors Serving:

• Private developers and entrepreneurs
• AEC firms needing overflow capacity

Arup: Engineering for a Shifting Earth

What does it take to design infrastructure that even endures an earthquake without worry? Arup has answered this question for more than 50 years. Civil engineers at the firm led the Presidio Parkway replacement near San Francisco’s Golden Gate Bridge.

Arup is also known for leading the design of the Texas Central High-Speed Train linking Dallas and Houston. The highly seasoned civil team of the company pairs closely with geotechnical experts on road, tunnel, and rail projects nationwide. In states like California, which is a seismically active region, such a level of structural rigor is how Arup has made an everlasting mark in the industry.

Capabilities:

• Seismic and tunnel design
• Rail and high-speed transit civil works
• Roads, bridges, and geotechnical engineering

Sectors Serving:

• Rail and transit authorities
• State transportation departments
• Property and urban development clients

WSP: Designing Transit Around the Rider

WSP approaches civil engineering through the passengers' eyes first. The firm designed the DART Silver Line in Dallas, which expanded regional rail access throughout North Texas.

The civil engineering team combines feasibility studies, structural design, environmental review, and detailed construction documents. WSP layers BIM into each stage to ensure optimal collaboration. As Sun Belt states like Texas continue to grow, that transit-first approach eases mounting congestion.

Capabilities:

• Rail and transit civil works
• Station and facility design
• BIM-driven infrastructure design

Sectors Serving:

• Transit authorities and municipalities
• State departments of transportation
• Urban and regional planning agencies

STV Group: Over a Century of Infrastructure Legacy

STV’s civil engineering roots can be traced back to 1912, long before interstate highways even existed. The firm extended its south-eastern reach in 2023 by acquiring AEI, a Kentucky-based civil engineering firm. That move added structural, geotechnical, and transportation design capacity across Tennessee, Kentucky, and Georgia.

The civil engineering team at STV also leads major transit facility projects for the MTA and other agencies. In rapidly evolving south-eastern markets, that bench strength helps the company meet rising infrastructure demand.

Capabilities:

• Civil site and transportation engineering
• Geotechnical and structural design

Sectors Serving:

• Transit and transportation agencies
• South-eastern U.S. municipalities
• Federal infrastructure programs

Stantec: Coastal Resilience at Growing Scale

Stantec further expanded its civil engineering bench by acquiring C3TS, adding 150 professionals along the Atlantic coast. That move itself increased the firm’s Florida headcount to over 350 across a dozen offices.

Stantec’s civil engineering experts deliver flood hazard mitigation, floodplain mapping, and stormwater management for municipalities along the coastal region. The firm also won Advisory Services Provider of the Year at the 2025 New Civil Engineer Awards. For America’s hurricane-prone coastlines, such high-level floodplain expertise ensures that homes and businesses are ideally protected.

Capabilities:

• Flood hazard mitigation and mapping
• Stormwater management design
• Site and land development engineering

Sectors Serving:

• Coastal and Gulf Coast municipalities
• Federal environmental agencies
• Private land developers

HDR: Employee-Owned, Water-Resource Focused

HDR is 100% employee-owned, and that ownership shows up in its civil engineering depth. This company has served the New Hampshire DOT for more than fifteen years from its Bedford office.

HDR’s civil team handles grading, stormwater management, wetland mitigation, and utility coordination. Hydrologic engineers at the firm also model floodplain and coastal hydraulics for water-stressed regions. In snowbelt and drought-exposed states alike, that unmatched expertise keeps infrastructure resilient.

Capabilities:

• Site civil design and grading
• Hydrologic and floodplain engineering
• Dams, levees, and water resources

Sectors Serving:

• State departments of transportation
• Water and wastewater utilities
• Municipal and federal clients

Arcadis: Global Scale, Local Resilience

While Arcadis is perhaps the largest European-based design and engineering organization, its civil footprint runs deep across the United States. Its team recently compressed a multi-month rail design process into ten weeks, leveraging integrated digital tools.

Arcadis merges civil design with geotechnical, structural, and transport engineering under a single roof. This firm also earned a Platinum EcoVadis sustainability rating in the current year. With climate volatility raising disruption costs nationwide, Arcadis’s resilience-first mindset drives every project.

Capabilities:

• Civil, transport, and geotechnical design
• Climate resilience and flood protection
• Data center and utility infrastructure

Sectors Serving:

• Municipal and regional governments
• Water and utility providers

Kimley-Horn: Site Civil Done Right

One of the most prominent projects of Kimley-Horn is one in which the company turned a 56-acre brownfield into Miami’s largest redevelopment project. The firm offers end-to-end civil engineering and permitting services across the USA.

Civil engineers at Kimley-Horn work alongside landscape architects, traffic engineers, and environmental scientists on every project. Such an integrated approach expedites permitting through Florida’s water districts and utility commissions.

Capabilities:

• Site civil and land development design
• Drainage and stormwater engineering
• Permitting and entitlement strategy

Sectors Serving:

• Commercial and mixed-use developers
• Municipal and utility clients
• Telecommunications and infrastructure owners

Michael Baker International: 85 Years and Counting

Michael Baker Intl. has spent over eight decades turning Pittsburgh roots into a countrywide civil engineering reach. Its civil and environmental practice manages projects not only in the USA, but in more than 40 countries.

Michael Baker designs bridges, highways, airports, and water and wastewater infrastructure for federal clients. This firm also added coastal engineering and mining specialties to its broad civil portfolio. Throughout hurricane- and flood-exposed regions, this degree of coastal expertise adds real protective value.

Capabilities:

• Highway, bridge, and airport civil design
• Water and wastewater infrastructure
• Coastal and environmental engineering

Sectors Serving:

• Federal and municipal governments
• Aviation and rail authorities
• Oil, gas, and industrial clients