All three restaurants at the Kennedy Center will be closed for as long as 12 weeks this winter and the centers concert hall shut down for about five weeks next summer to permit repairs of extensive damage caused by leaking water throughout the building.

The long awaited repair work will begin now that a $4.7 million appropriation from congress is available.

The first contract - about $500,000 to re-waterproof the floor of the kitchen that serves all three restaurants and to fix a balky drainage system for the canopy overhanging the center's roof terrace - is expected to be awarded soon.

The $70-million center, which opened six years ago, has been plagued with structural problems, almost from the outset. Water leakage, both from rainfall and from spillage in the center's kitchen, has caused stains, smears and occasional falling plaster in various parts of the complex.

A series of thunderstorms last July caused new leaks in the grand foyer, where small amounts of plaster fell fromthree spots in the ceiling.

Workmen have erected elaborate wooden covered walkways in the foyer and have laid down a temporary waterproof plastic membrane on the roof terrace above, stepping the leakage. The wooden walkways are in the foyer, and the roof terrace over the foyr remains closed to the public.

Work on the kitchen and canopy could begin as soon as Jan. 9 according to Thomas Kendrick, the center's director of operations, and the three restaurants - La Grande Scene. The Gallery and The Bufferteria - could be closed until as late as March 31.

The kitchen is on the top floor of the center and is situated over a portion of the concert ball. Water accumulating on the kitchen floor has seeped into the concert hall ceiling and walls below causing discoloration and peeling paint.

kendrick said the concert hall is scheduled to be closed from July 5 to Aug. 15 for repainting, and also for replacement of some of the wallscaping carpet-like material on the walls that has become discolored from seeping water.

Kendrick said the closing of the hall wall not cause the cancellation or postponement of any programs.

"We anticipated the thing a long time ageo and suspended lookings for the summer in the concert hall," he said.

In additin to the kitchen, concert half and canopy jobs, Kendrick said other major repair projects will include waterproofing the 80,000 square foot roof terrace that overlooks the Potomac river and plugging leaks in the cast plaza drive the rampway to the center's main entrances under which there are numerous store rooms, dressing rooms and other facilities that have suffered water damage.

Kendrick stressed that damage throughout the ccomplex consists primarily of peeling paint and [WORDS ILLEGIBLE]in Skim plaster" with no threat to the structural soundness of the building.

In addition to periodic patch work done since the center opened in September, 1971, a major $150,000 repair job was started in November, 1976, on the central roof area, which had sprung several leaks. That job done with funds separate from the more recently appropriated $4.7 million from Congress was completed last May.

"The roof is now tight," said Kendrick, "under a five year guarantee."

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