Its many green features have helped win T.C. Williams High School a gold medal for the Best New Construction Design of a High School. Moseley Architects took the prize, from the Council of Educational Planners International. The project is also up for certification by the U.S. Green Building Council as a Leader in Energy and Environmental Design. 

With 2,500 students expected over the next seven years, the new building opened last September. Its 461,000 square feet occupy the same 22-acre lot as the older, smaller facility, which was built in 1965 and demolished this January.

The new school still displays the Colonial style that distinguishes so many public buildings throughout Northern Virginia. But its environmental features show its innovative spirit.

The roof is planted with 10,000 square feet of vegetation, reported Byrna Dunn, environmental planning and research director for Moseley Architects, in describing some of the more dramatic innovations. Pavers were also installed on the roof, so the students can stand there to enjoy the view. In addition, she said, Many of the classrooms overlook the planted roofs. They also help with storm water management: The plants absorb the water. Seventy-five percent of one-inch storm waters are absorbed by the soil that way.

Beneath those roofs, she added, Over 90 percent of the classrooms enjoy natural daylight. Some dont even have to turn the electric lights on. Daylight enhances learning, she claimed, while also saving electricity. As an added benefit, it creates an exciting modern exterior, with its expansive walls of windows.

Under the school, a 450,000-gallon cistern collects all the rain that runs off from the unplanted parts of the roof. The remaining roof sends the water down the pipes, where it is used for flushing toilets, irrigation and air conditioning. she said, If you see blue water in toilets there, it has been flushed from the cistern. Waterless urinals reduce the usage even further. As a result, she said, We save more than five million gallons of drinking water per year.

At a cost of $87.7 million, she said, the project cost somewhat more than other Virginia high schools. But because it is the only high school in Alexandria, it houses all the special programs that are often distributed among other districts. And, she points out, it also makes the building itself into a teaching tool, for both the students and the general public, including those who are looking for ways to make their own homes green.