Steven F. Udvar-Hazy Center Construction

Smithsonian Team Restores Manassas National Battlefield Park Wetlands

Construction often impacts wetlands, which are defined by the US Environmental Protection Agency as "areas where water covers the soil, or is present at or near the surface of the soil." Wetlands are identified, in part, by the types of trees and plants found there. Architects and field representatives of the Army Corps of Engineers helped the Smithsonian carefully position the new Steven F. Udvar-Hazy Center and its roadways on property at Washington Dulles International Airport so that impact to wetlands was kept to a minimum. Only 7 acres of wetlands on the 176-acre site have been disturbed.Most of the trees on the building site that were harvested prior to construction were pine, planted in the 1950s by the airport on land that had formerly been farmed. This aerial photo shows the Dulles International Airport with the future 176-acre Steven F. Udvar-Hazy Center site outlined in red in the lower right corner (southeast), and this is the land that was prepared for the new museum.

By law, owners and developers -- including the federal government -- who have disturbed wetlands must compensate -- or mitigate -- that disturbance by restoring or creating similar ecological systems, preferably in the same geographical area. This ensures that the overall acreage of wetlands will not be decreased and that the plants and wildlife that thrive there will continue to have a home.

To compensate for the disturbed wetlands, the Smithsonian was directed by the Army Corps of Engineers and the Virginia Department of Environmental Quality to create 15 acres of new wetlands. However, there were no opportunities for doing so at Dulles. After an extensive search of other public properties in the Dulles corridor, the National Air and Space Museum contacted the Superintendent at the nearby Manassas National Battlefield Park . Superintendent Robert Sutton had several candidate wetlands projects in mind and invited the Smithsonian to explore them with the Park's staff.

The Manassas site that needed the greatest restoration was the 558-acre Stuart's Hill Tract. Although this land saw significant Civil War action, it was not part of the original park. In 1988 a developer began to prepare this site for commercial and residential construction, clearing the land, diverting a stream, and altering the landscape drastically. Congress bought the property in 1988 in response to protests from historians, environmentalists, and citizens who believed that the land should be preserved as part of the Battlefield. But the Park Service did not have the funding required to restore the abandoned construction site. However, there was a good plan for doing so.

Under contract with the Park Service, in 1992 the University of Georgia School of Design created a plan for restoring Stuart's Hill to its 1860s configuration. As explained by Bob Sutton, the University's design was quite accurate because of an incident that took place during the Second Battle of Manassas. Fitz John Porter, a Union corps commander, was court-martialed for his actions in that battle. The charges against him were related primarily to his actions on the second day of the battle, August 29, 1862. His defense was largely based on the presence of Confederate forces in his front that blocked his intended path of advance on the 29th and prevented him from complying with orders. Also, an order to attack issued late in the afternoon reached Porter too late for him to launch an assault. An Army board of review was convened in 1878 to rehear the case and issued its findings in 1879, reversing the decision of the earlier court martial. The Army directed a cartographic engineer to map the area for the trial, and the resulting documents gave the court - and the designers at the University of Georgia - an excellent picture of the land in 1862. More recent aerial photos show how the topography and plant life have changed since the War.

With funding from the Commonwealth of Virginia, as part of the state's generous support of the Udvar-Hazy Center, the Smithsonian proposed to implement the University of Georgia's plan. Doing so would restore wetlands on the easternmost 45 acres of the tract, thereby satisfying the Corps of Engineers' requirements for restoring wetlands disturbed during the construction project at Dulles.

As shown in the left aerial photo, the Stuart's Hill Tract is framed today by Virginia's Lee Highway to the north and Interstate 66 to the south. In the close-up view, right, evidence of the developer's work is easy to see: a paved street comes in from the right, other streets are graded, trees and vegetation have been removed, and elevations are markedly altered. Aerial photos courtesy of the National Park Service.

Before Congress bought the Stuart's Hill property, the developer had flattened ridges, cleared trees, graded land for streets, laid drainage pipe and culverts, and paved an access street (see aerial photos above, and photos below). Restoration of the area would require that some 95,000 cubic meters of material be moved around the site.

Concrete for manholes, such as these, needed to be removed and the holes filled. Photos by Smithsonian staff

In early 2000, the Army Corps of Engineers issued permits to the Smithsonian, which assembled a team to proceed with the project:

• URS Corp., a sub-contractor to Hellmuth, Obata + Kassabaum (architect for the Steven F. Udvar-Hazy Center) - project design.
• Environmental Quality Resources, L.L.C. - construction and wetlands restoration work.
• Parsons Brinckerhoff Construction Services - construction management.

Virginia's environmental quality staff established requirements for the mitigation project, while the Corps of Engineers issued all the necessary permits. Park Service staff provided historical guidance throughout the design and construction phases.

David Hay, design manager for the Smithsonian, and Byran Gorsira of the National Park Service, worked with the various contractors and organizations to plan the landscaping and create wetlands that would fully satisfy historic and environmental needs. The designer used the University of Georgia plan, the 1862 survey data, more recent archival material, and aerial photographs to define a specific scope of work. The project would include:

• Rebuilding ridges, some of which would require adding several meters of dirt to landscape elevations (many of these ridges were important in the tactics used during Civil War skirmishes - and to interpreting them).
• Removing soil from areas that formerly held water, reestablishing those wet areas so that plants could thrive.
• Replacing shale, which would not hold water, with clay and organic material.
• Removing all concrete, culverts, pipes, and other evidence of the developer's work.
• Removing non-native plants that had invaded during the past 140 years.
• Planting trees and plants that would have been present in 1862.

Extensive earthmoving was done to restore the Stuart's Hill Tract to the contours of 1862. Photo courtesy of Parsons Brinckerhoff Construction Services.

Shale does not hold water and it was removed. Photo courtesy of Parsons Brinckerhoff Construction Services.

As explained by Rick Scaffidi, Environmental Quality Resources, the greatest challenge in restoring the site was to maintain a 0.1-ft (0.03-meter) precision in the elevation of the contoured land so that the wetland cells would work, thus retaining the proper amount of water to ensure that plantings would flourish. Heavy equipment was used by EQR to move the 95,000 cubic yards of material. Photo by Smithsonian staff

Timely rains in September 2003 showed that landscaping designs had been successful in retaining water for the wetlands. Photo courtesy of Parsons Brinckerhoff Construction Services.

The following table is a list of plants and trees that have been planted at the Stuart's Hill tract during the Smithsonian's restoration project. Open fields were also seeded and mulched.

Rick said that it took about a month to put in place almost 57,000 plantings. Key to the process was having just the right amount of water present. The local deer found the young plants to be an irresistible source of food, so EQR protected trees with tubes and the young plants with repellant spray.

The contract team wanted to minimize the impact of their work on local wildlife, particularly if those species would have been present in 1862. When turtles were discovered on the tract, for example, a Boy Scout developed an Eagle Scout project to relocate them. Several scouts were mobilized into a weekend "Turtle Round-up," during which they scoured the site, picked up turtles, temporarily relocated them to a "turtle corral," and then returned them to the site upon completion of the restoration.

The National Park Service is particularly concerned with historic areas. They identified a gravesite on the southeast edge of the project and asked for grading that will make archaeological investigations possible in the future.

EQR completed the project in 131 days, spending over 10,000 staff hours on the job. But the work is not done. The Smithsonian Institution, through its contractor URS Corp., has a five-year obligation to monitor and maintain the area to ensure that plantings survive and flourish. Superintendent Sutton believes that the five-year period will make sure that plants mature and that non-native species are not re-introduced. After 2008, the NPS will continue to monitor the mix of wetlands plants.

Work was completed on schedule in early November 2003. Visitors can already access the newly restored meadow, and when additional funding becomes available a picnic shelter will be built nearby. Following the regrading and landscaping, water from recent rains is held by the earth, giving wetlands plants the environment they need to grow. Photo by Bill Doole

Robert Sutton, David Hay, and Rick Scaffidi all agree that this project is a classic example of cooperation among government agencies. The Smithsonian found an economical way to meet its wetlands mitigation obligation; the Park Service can now preserve the Civil War story of the region; the Corps of Engineers worked with both to approve this unique approach; and the Commonwealth of Virginia provided the funding.

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