Intercounty Connector Contract B, the middle segment of the ICC automated tollway, consists of a new 7.1-mile, six-lane divided highway that links the Montgomery County, Md., technology corridor and Interstate 270/370 to the west, with the commercial corridor and I-95 to the east, extending into neighboring Prince George's County.
The $560-million project included a diamond interchange and a single-point urban interchange. Of the project's 10 bridges, five were built with steel girders to carry state and local crossroad traffic over the ICC.
Four dual-structure mainline bridges used 95-in. bulb-tee girders to span lengths ranging from 105 ft to 165 ft. The fifth mainline bridge is built from 84-in. to 90-in. steel-plate curved girders spanning up to 248 ft.
Since the project was constructed through public parks and residential areas, extensive public relations and environmental efforts were made. To keep animals safe, culverts were designed for fish, small mammal and amphibian passage.
A permanent 8-ft-high fence was designed to protect deer, with tighter fencing at the base to keep smaller animals out of the construction zone. Highway escape ramps were built for wildlife.
To protect eastern box turtles, specially trained dogs located and retrieved the turtles, and environmental specialists relocated them outside the project's right-of-way. Volunteers from the construction and design team also pitched in with the relocation process. Best Projects judges felt these efforts far exceeded industry standards.
The project required extensive stormwater management design, since the roadway traverses miles of watersheds.
In addition to underground stormwater facilities, above-ground retention basins were designed not to hold a permanent pool of water, to minimize thermal impact to native fish species when the water is discharged. Two tributaries were relocated and restored.
Construction also included more than 7 miles of sound barriers and more than 62,000 sq ft of mechanically stabilized earth walls. An extensive intelligent transportation system and electronic toll collection components were installed.
General Contractor: Kiewit Infrastructure South Co., Peachtree City, Ga.
Owner: Maryland State Highway Administration, Beltsville, Md.
Lead Design & Structural Engineer: Parsons, Beltsville, Md.
Civil Engineer: KCI, Baltimore
MOT, Roadway and Structural Design: Gannett Fleming, Baltimore
Submitted by Parsons
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