Nearly 4,000 people contributed more than $200 million toward the 150,000-square-foot expansion and renovation project.
"We are on schedule and only slightly over budget," Wilson said after digging into the dirt with a gold-painted shovel.
Construction on an underground parking garage will begin today, with bulldozers uprooting the asphalt and street lights in the existing parking lot north of the museum, he said.
The underground facility will be topped with a reflecting pool at ground level, with skylights bringing in natural light to the parking areas below. The garage, which has space for 450 cars, will open in mid-2002.
After the garage's completion, work will begin on the Henry W. and Marion H. Bloch Gallery of Art. The new building -- an 840-foot-long structure on the east side of the museum -- will house underground galleries. The galleries will be lit by five above-ground glass boxes that will diffuse natural light into the areas below.
The gallery, expected to open in 2005, is named for Henry W. Bloch, a trustee of the museum and chairman of the museum's building committee, and his wife.
"As important as the new building is what it houses and how it houses it," said Don Hall, senior trustee of the museum.
The new addition will double the museum's space for special exhibitions and showcase its modern and contemporary art, African art and photography collections. The building will house a new entry lobby, library and sculpture court featuring works by Isamu Noguchi.
In addition, the ground floor of the existing building will be renovated to triple the size of the museum's educational facilities.
The parking garage and gallery building were designed by Steven Holl, an architect based in New York City. The concept for the Nelson-Atkins project won an American Institute of Architects-New York City Chapter design award last May.
"It's a sparkling design and an absolute jewel of a building," Hall said.
-- Features-arts editor Jan Biles can be reached at 832-7146.