InterCounty Connector

ICC Contract B is the third and final contract connecting two major Washington, DC metropolitan areas. Kiewit was awarded this $550 million, 7-mile highway project not because the team offered the lowest bid, but because of their approach to the environmental components. ICC Contract B includes the challenges of balancing an aggressive job schedule with exceeding the tough erosion and sediment control standards of Maryland throughout several stream valleys and a 2-mile-long environmental special protection area.

For completion, it is critical to schedule work around the two distinct local watersheds the project crosses. Each watershed has a specific stream closure period. Some of the environmental challenges include redundant erosion, sediment controls and environmental design, as well as construction and inspection teams, and specialized construction methods in constricted work areas to minimize any environmental footprints.

Along with 10 bridge structures, nearly 2 million cubic yards of grading work must be completed in 2010. Throughout this heavily phased process, erosion and sediment controls must be installed, maintained and often redundant to one another. In the special protection areas, it is a common requirement to have a super silt fence side-by-side, oversized ponds and parallel berms. To maintain the 7 miles of controls, 600 hours per week are spent stabilizing material, patching fences, cleaning outlet structures and gabion baskets and rebuilding earth berms.

Environmental quality control is a significant portion of the project budget in all phases of design and construction. Third-party design inspections and audits are performed on every design package submitted to the owner for approval. On the construction side, a third-party environmental team, designated with green hard hats, provides knowledge and support to the production crews regarding dewatering, material storage and wildlife relocation, specifically the Eastern Box Turtle.

As the ICC Contract B crosses over sensitive stream valleys, special care in design was taken to ensure environmental impacts were mitigated. For example, the initial drawings had limited the right-of-way, it was nearly impossible to set the fascia girders on some bridges. Limit of disturbance "bump outs" had to be presented to and approved by the client and environmental agencies to allow for girder erection. Also, while clearing the site, the owner had recognized certain trees as "specimen trees" to be saved for future stream bank restorations within the project. About 1,100 trees up to 60 feet long were specially cut, sparing either the roots or the branches, stored and transported to an offsite area for future use.