The board of the North Texas Tollway Authority has hired Prairie Link Constructors LLC, a team composed of Fluor EPCM Services, Irving, Texas, and Balfour Beatty Infrastructure Inc., Atlanta, to build Phase 4 of state Highway 161 in the agency’s first design-build contract, worth $414 million. The winning effort was 32% lower than the authority’s original $610-million estimate for the project. Prairie Link Constructors also includes the Fort Worth office of AECOM Technology Corp. as designer, Richardson, Texas-based Halff Associates for drainage design, and PSI, Oakbrook Terrace, Ill., to handle independent quality assurance and control. The phase includes 6.5 miles
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.