Walter Reed National Military Medical Center
The Walter Reed National Military Medical Center (WRNMMC) cares for our nation’s most critically wounded warriors, our veterans, and their families. To accommodate the relocation of Walter Reed Army Medical Center to the National Naval Medical Center (NNMC) campus, Clark, along with joint venture and design-build partners, delivered 725,000 square feet of new construction and performed approximately 500,000 square feet of renovations.
A project under the Defense Base Realignment and Closure (BRAC) Commission, WRNMMC is one of the military's flagship healthcare facilities. Clark, working collaboratively with the government and various project partners, took an integrated "one team" approach to design and construction, driving the project toward its successful completion.
New construction for the WRNMMC emcompasses two buildings—the America Building and the Arrowhead Building—and two parking structures. The 560,000 square-foot America Building is the military health system’s largest ambulatory building. The six-story outpatient facility provides services for cancer patients, amputees and other outpatient clinical needs. The Arrowhead Building is a 165,000 square-foot, four-story addition to NNMC’s existing hospital. It houses emergency in-patient services. The project team also constructed two parking structures, adding 2,150 parking spaces, and performed associated traffic improvements, including two secure gate entrances.
Extensive renovations to NNMC’s existing facilities were required to consolidate the two hospitals. In total, Clark and its project partners renovated 46 different medical departments. The team developed unique plans for each before starting work, including comprehensive infection control risk assessments (ICRA) to measure airborne toxins. All renovation work occurred above, below, or immediately adjacent to ongoing hospital functions with no impact on medical operations.
The joint venture team delivered the new inpatient and outpatient hospital construction within an unprecedented 30-month timeframe. By fully integrating the key stakeholders and the design and construction personnel, the team successfully met all project challenges.
The America Building, Arrowhead Building, and the Patient Parking Garage—all new construction—are LEED Gold certified. The Navy required LEED Silver for this project, but the design-build team voluntarily went beyond the project requirements. The Medical Center's heating, ventilation, and cooling systems incorporate cutting-edge technology such as high-efficiency, water-cooled centrifugal chillers, which reduce energy consumption by 28 percent. An Enthalpy heat recovery wheel transfers energy between exhaust and incoming outside air and allows building occupants to enjoy 100 percent outside air in lieu of re-circulated air.
Other sustainable features include a storm water system, native and adaptive landscaping, low-flow fixtures, and light pollution controls. Additionally, the project team's innovative construction waste management plan diverted 89 percent of waste from landfills.
In order to meet the client’s delivery date, construction at Walter Reed began before the design documents were complete. This schedule push made managing information critical for the project team.
Clark Concrete led concrete operations on site and worked closely with the construction joint venture team and the architect of record to allow work to commence while design efforts were still underway.
In the America Building, Clark Concrete used a flying form system for the construction of the cast-in-place decks. This table system saved both time and money. Additionally, Clark Concrete operated an on-site batch plant to improve work flow predictability. The batch plant was able to service up to three deck pours in one day, including pours that totaled over 900 cubic yards.
The three linear accelerators (LINACs), used for radiation treatment, are located in the basement of the America Building and proved to be a challenging piece of the construction puzzle. The walls of the LINACs are four feet thick and its roof is four feet thick with a four-foot-deep by 12-foot-wide beam running the length of the three rooms. These rooms, as well as the HDR and Brachytherapy rooms, required a dry density of 147 pounds per cubic foot or higher. Clark Concrete modified the standard 4,000-pound-per-square-inch mix to create a mix with a dry density of 153 pounds per cubic foot.