Mayor Marion Barry yesterday announced a $35 million, joint government-private program to rehabilitate 733 of the estimated 4,500 vacant, boarded-up housing units in the city.

Much of the housing rehabilitation will take place in the areas affected by the 1968 riots and subsequent renewal programs and is slated for moderate and low income families.

Standing amid flaking plaster and shattered windows in one of the houses targeted for improvements in the 100 block of Bates Street NW, Barry called his plan "the most ambitious program in public-private housing" in the city's history.

Private lending institutions have pledged $25 million in loan funds for the project, and about $10.46 million in city monies will be used, Barry said. Developers and sponsors have already been selected for most of the projects.

All 733 units should be rehabilitated by November, 1980. according to city officials. When completed, the program will include rental housing, condominiums, cooperatives, public housing and 200 single-family homes.

City officials said their aim is to create "economically integrated communities."

While the majority of the units will go to lower and moderate income families, some will be sold at market rates. Families displaced by urban renewal will have first priority, officials said.

Some of the properties will also be used as part of the District's "urban homesteading" program, which in the past has allowed families to purchase some homes for as little as one dollar each.

Some of the lower income families will be able to borrow up to $11,000 in down payment funds, according to Robert L. Moore, director of the city's Housing and Community Development Department.

Officials estimated that more than 2,200 construction and building trade workers will be hired to complete the rehabilitation projects. "The majority of the work will be done by minority contractors," Harry said yesterday.

The mayor said his plan will "take the boards off" 98 per cent of the cityowned vacant housing. But by the city's own estimate, it owns 1,019 housing units that are either vacant or partially occupied. City officials estimate there are another 3,500 privately owned vacant housing units but stress this is a rough estimate.

Meanwhile, city figures show 7,489 people on the public housing waiting list alone, and thousands more are seeking improved housing at affordable prices.

To provide housing for all who need it, Barry said, "We need help from the federal government in a massive way... The housing crisis can't be solved by the D.C. government alone."

For the program announced yesterday, the city is using federal community development block grant funds to provide its $10 million in loans, city officials said. They said $4.5 million of that amount already is available in unused funds from past years, and HUD and the D.C. City Council have been asked to approve the reprogramming of the additional funds.

Nearly one-fourth of all the units that are to be rehabilitated under Barry's plan are in the Bates Street area.

The street, just a few blocks north of the Capitol, has for years been in one of the city's worst slum areas and has been the focus of government promises. The U.S. Department of Housing and Urban Development approved a rehabilitation plan for the area as early as 1969, for example, but the streets are still lined with dozens of burned-out, gutted rowhouses whose windows and doors are boarded with plywood.

Last July, Barry, then campaigning for mayor, released his housing platform at a Bates Street press conference.

Yesterday, he said, "I have pledged to get the boards off the houses that are owned by the D.C. government, make them livable and put people back into them." "I am here today to keep that pledge."

One-third of the vacant houses on Bates Street will be rehabilitated for rental housing. one-third sold to lower income and moderate-income families, and one-third sold at market rate prices of $65,000 or $70,000, Barry said.

In addition, he said, the city will provide low interest loans to existing Bates Street homeowners who want to fix up their homes, as well as require investor-owners in the area to rehabilitate their properties. Streets, alleys and sidewalks will be upgraded, he said.

Forty of the Bates Street homes will be sold at prices ranging from $38.000 to $44,000 under a federal program that subsidizes interest rates so moderate-income homeowners will pay less in monthly mortgage payments.

Under the overall program announced yesterday, 184 public housing units will be rehabilitated. Six buildings in the 1400 block of Girard Street NW also are to be fixed up. The other properties are scattered with some in neighborhoods where private renovation is extensive and homes are selling for up to $100,000, realtors say.

Developers participating in Barry's program include the D.C. Development Corp., the D.C. Housing Industry Corp. and the Washington Residential Coalition. In one case, Patricia Rice Press, a businesswoman active in real estate who ran unsuccessfully for a Ward Six City Council last year, has been tentatively selected to purchase a large residence at 18 Logan Circle NW and is slated to receive loans at three percent interest to fix up the building that is to include one rental unit for a low-income family, city officials said.