Natural beauty is what draws people to Merchants Millpond State Park in Gatesville, N.C. Its 760-acre lake and adjacent swamp are home to towering bald cypress and tupelo gum trees, primitive species of fish, and a countless variety of birds. Helping visitors understand the park’s unique ecosystem is a challenge, fostered by a new 7,500-square-foot visitor center, which demonstrates that even small buildings can have an important, and positive, environmental impact.
Designed by Frank Harmon Architect, of Raleigh, N.C., the modest, wood-framed structure incorporates a low-tech approach to sustainable design and recalls a historic mill that once occupied the site. “I promised the client our building would have the feel of the old mill,” says design principal Frank Harmon. “It wouldn’t look like the old building, but it would have the qualities of a rustic, wooden structure with rafters and deep overhangs.”
The park’s steady flow of visitors and its popularity among school groups of all ages—coupled with the fact that, for years, the park’s staff of seven had been shoehorned into a 700-square-foot building near a campground—begged for a modern facility. Of particular importance was room to house a new exhibition about the site’s four primary habitats. The staff also asked for lecture and activities spaces.
Harmon placed the visitor center on the brow of a low hill—parallel to the bank of the pond—so that every space in the building enjoys southeast views of the natural surroundings. This solar orientation works hand-in-hand with the center’s broad shed roof, which angles upward to the northwest and fills the rooms with soft daylight spilling through clerestory windows.
Visitors enter beneath a low roof into a lobby whose ceiling slopes upward to frame a vista of the tall trees. “That was our big gesture,” Harmon says. “It seemed the right thing to do.” The southwestern end of the building houses a 60-seat auditorium and a classroom outfitted with microscopes and kid-sized lab tables. Outside, a long, shady porch stretches along the sunniest exposure.
Harmon envisioned the visitor center as “a big, well-lighted tent” with lots of flexibility. The building is not only economical—constructed simply with 2x6s, 2x10s, and prefab wood trusses—but also green, with a target of LEED Gold. The exterior rainscreen wall is cypress, reclaimed from the nearby Great Dismal Swamp National Wildlife Refuge after Hurricane Isabel ravaged many old trees. Flooring in the lobby and exhibit area is recycled heart pine. Other materials include recycled steel structural members, concrete block with high fly-ash content, and a standing seam metal roof, whose high solar reflectivity reduces heat gain.
The building systems are sustainable, too. A ground-coupled heat pump provides heating and cooling. Daylight sensors contribute to energy savings by allowing only certain lights to come on when needed. Outside, a corrugated steel cistern captures rainwater from the roof—reducing stormwater runoff from the site while providing water for irrigation and hosing down canoes.
Park superintendent Jay Greenwood notes that environmental education is a top priority for the North Carolina Division of Parks and Recreation. While the Merchants Millpond Visitor Center is the North Carolina park system’s first LEED-rated building, all new facilities in the division are being designed with LEED certification as a goal. “We talk a lot about the importance of managing habitats, so anything that we can do to protect the environment is important to us,” Greenwood says. “That’s our main theme.”