Clark Construction Group LLC

Architect:

WDG Architecture, PLLC HOK Perkins + Will McKissack & McKissack

Client:

General Services Administration

Scope Of Work

The U.S. Coast Guard Headquarters, completed under a design-build contract, sits on the west campus of the former St. Elizabeths Hospital and is the first phase of the Department of Homeland Security’s planned relocation. The largest construction undertaking in the General Service Administration's (GSA) history, Clark completed the project on time and within budget.

The U.S. Coast Guard Headquarters consolidated a workforce of nearly 4,000 employees, who were previously scattered among 24 locations around Washington, D.C. The 1.2 million square-foot, 11-level office building is the central component of the 176-acre campus, as well as its most unique element. The structure is built into the sloping hillside and only two of the levels are entirely above-grade. The lower nine are built into—and extend out from—the hillside. The building consists of linked, quadrangles, clad in brick, schist stone, glass, and metal that follow the site's natural change in elevation and cascade toward the Anacostia River. Clark also managed the interior fit-out of the building, which included installing audio/visual equipment, telecommunications systems, and security features.

In addition to the headquarters building, the Clark team was responsible for an 800,000 square-foot, 1,973-space parking garage and a central utility plant. Under a separate $29.5 million contract, Clark also delivered the Department of Homeland Security's National Operations Center, a mission critical space  within the U.S. Coast Guard Headquarters building.

The U.S. Coast Guard Headquarters project is one of the largest construction efforts in recent Washington, D.C. history. The completed project features 500,000 bricks, more than eight million pounds of stone, 300 miles of electrical wire, and 55 miles of piping. Despite the complexity of managing such a large scale endeavor the design-build team showed tireless commitment to finishing on time and on budget. They took on scopes above and beyond the original contract requirements and managed the work.

The headquarters building satisfies GSA’s most stringent security requirements for a level four facility incorporating stand-off distances, hardened façades, and structural systems resistant to progressive collapse.

Self-Perform Work

Critical to this project were Clark's own self-perform companies. Clark Foundations and Clark Concrete were responsible for 33 percent of the work on the U.S. Coast Guard Headquarters project, including the excavation, support of excavation, and cast-in-place concrete work.

With the sprawling building footprint over the steep site, 1.6 million cubic yards of soils were excavated, requiring 300,000 square feet of timber lagging and 1,500 soldier piles. Due to geotechnical soil conditions, the foundations plan was comprised of 1,500 caissons, up to eight feet wide and 100 feet deep.

After surmounting the less than ideal soil conditions, the project team navigated the placement of 250,000 cubic yards of concrete throughout the headquarters, garage, and CUP.

Sustainability

Highlighting the project's  Gold certification are the sprawling 450,000 square feet of green roof installed on top of the headquarters and garage. A massive retention pond at the lowest level of the headquarters collects runoff from the entire St. Elizabeths West Campus and feeds the roof and courtyard irrigation system. Mechanical and electrical systems are the most energy efficient available, and materials were meticulously tracked to maintain regional supply chains.

More than 40 percent of all construction materials used in the project have been salvaged, harvested, extracted, mined or manufactured within 500 miles of the job site, helping to further reduce the project’s carbon footprint.

S2N Technology

S2N provided design services for the low voltage technologies for the new U.S. Coast Guard Headquarters. In addition to design, S2N also provided QA/QC services to Clark Construction for the installation of these technologies.