Mayor Marion Barry yesterday $162 million proposed in capital improvements to the District's roads, buildings and communications facilities in fiscal 1989, which would bring to $1.1 billion the total spending limit authorized for capital projects in the city.

The $162 million figure marks a sharp decline in proposed new spending from a year ago, reflecting an effort by city officials to cut the cost of servicing debts incurred to pay for long-term projects.

Nearly $270 million in new capital spending was authorized for the 1988 fiscal year that ends in September.

Payments from the D.C. treasury to service the city's debts are expected to reach almost $221 million this year and increase to nearly $238 million next year, or more than 8 percent of the District's total budget.

"Times are getting tough for capital money," Barry told reporters yesterday. "I don't think the public wants us to spend but so much money."

On another long-term spending issue, Barry deflected questions about whether the District will fund construction of a new stadium for the Washington Redskins. Team owner Jack Kent Cooke recently suggested he would seek bids from neighboring jurisdictions if the city does not respond by June 30 to his request for a larger, domed facility.

"The Redskins are ours," Barry said. "We're going to keep them. And I hope that's the end of that question." Barry said that he has asked his aides to "study" Cooke's proposal for a 75,000-seat, domed stadium.

Among the potpourri of 89 projects anticipated in the 1989 capital authorization request are $31.5 million in improvements to city streets, $18 million to upgrade public housing, a $7.5 million computerized communications system for the city's ambulance service and $600,000 for a new police helicopter.

But with nearly $1 billion in other projects approved in previous years still on the drawing board, perhaps only 10 percent of the new proposals will receive funding in the coming year, said Diana Carsey, director of the budget office's Capital Improvements Program.

"The challenge is to finance everything and stay within my limits," said Carsey. "It's not possible. You can't do it."

Plans call for the city to pay for capital projects in fiscal 1988 by borrowing $154 million in April through sales of general obligation bonds.

An additional $200 million in borrowing is anticipated for 1989 and no more than $155 million annually thereafter.

Long delays between budget authorization and actual spending -- dictated partly by limits on the city's ability to borrow funds and make interest payments -- have been an issue of mounting concern to District officials.

Delays also have been caused by contracting and design problems. For instance, long-awaited renovations to the 444-unit Barry Farms public housing in Southeast originally were approved in a 1982 capital authorization of $22 million. But housing officials were unable to contract for the construction within budget limits, even after an additional $8 million was authorized in 1987.

Some agencies have responded to administration requests to pare back capital spending authorizations.

The University of the District of Columbia, for example, recently agreed to rescind plans for five projects totaling $345,000, including a new sprinkler system for the athletic field.

But Carsey described that amount as small compared with the university's remaining balance of $93 million in spending authority.