A robust transportation sector in Texas as well as continued vitality from energy, infrastructure, education and hospital projects in Texas and Louisiana helped deliver a high-performance 2014 for design firms based or working in the Gulf Coast.

The top 75 firms in ENR Texas & Louisiana's annual ranking of the region's largest designers reported combined revenue of $5.1 billion last year, compared with $4.1 billion in 2013—a nearly 25% increase that extends a three-year growth spurt in the region.

The top three firms—S&B Engineers and Constructors Ltd., Burns & McDonnell and AECOM—each exceeded $400 million in total contracts.

"The large firms had banner years, and many projects involving infrastructure, health care and energy are large in scale," says Anirban Basu, chief economist with Washington, D.C.-based Associated Builders and Contractors. "As a result, demand has been high for subcontractors in Texas and Louisiana."

Last year, both states added construction jobs at rates exceeding the national average. From December 2013 to December 2014, construction employment increased 8.7% in Texas, 7.8% in Louisiana and 5.7% in the U.S., says Ken Simonson, chief economist with Arlington, Va.-based Associated General Contractors of America.

Texas continues to benefit from high population growth. "Rapid growth creates demand for housing, retail, hotel, medical, transportation and other consumer-related construction, adding to state and local tax bases," says Simonson. "The additional revenue helps fund construction of schools and other public facilities."

"Infrastructure-related construction also typically expands as population increases," Basu adds.

In Texas, transportation work is booming, from the $818-million Dallas Horseshoe, a project involving improvements to Interstates 30 and 35E, to the $2.4-billion reconstruction of metro Houston's U.S. 290, a major east-west artery.

LJA Engineering Inc., Houston, is working on another Houston roadway project that calls for a pair of direct connectors for the $34-million Hardy Toll Road/S.H. 99 Interchange in addition to widening Hardy Toll Road and Riley Fuzzel overpass, says Dan Copps, LJA senior vice president.

The Gulf Coast also is seeing its fair share of institutional work, with the Houston office of architect Perkins+Will having designed the 430,000-sq-ft Patrick F. Taylor Engineering Building at Louisiana State University-Baton Rouge, one of the largest educational projects ever undertaken by the state, experts say.