The community of Marshall Heights, part of the area east of the Anacostia River long regarded by residents as the "forgotten" Washington, celebrated an economic boost yesterday with groundbreaking ceremonies for a new $15 million nursing home complex.

Located on 50th Street and Nannie Helen Burroughs Avenue, the 17,500-square-foot Grant Park Nursing Home will be the largest construction project in Ward 7 in recent years.

The facility will employ 230 workers and will house a 296-bed nursing home, a medical clinic, dental clinic, a drugstore and a gift shop. It is scheduled to be completed in the fall of 1983.

Richard A. Hamilton, chairman of the Marshall Heights Community Development Organization, said the new project means "businesses don't have to flee Ward 7 anymore and go to the suburbs. We are taking a new attitude around here about development. We want citizens to take pride in this community."

Heralding the importance of the facility, a host of political candidates, including Mayor Marion Barry and City Council members Betty Ann Kane and David A. Clarke, appeared at yesterday's groundbreaking ceremonies.

"This will be a comprehensive facility," Barry told the audience, "where people in Northeast Washington can get all of their health and medical needs addressed in one place."

The project is being built by the team of developer Harry D. Calhoun of Washington and the Atlanta-based Consolidated Resources Corp. of America with funds secured from the Department of Housing and Urban Development.

Residents of Ward 7 welcomed the attention provided by yesterday's ceremony and said new development in their community is long overdue.

"I'm glad we're getting the new building, the drugstore especially," said Marion Lucas, a retired Census Bureau employe. "We don't even have a drug store in the area now. The nearest one is 12 blocks away on Minnesota Avenue."

Ward 7, which lies east of the Anacostia River, is a diverse mixture of the middle class and the poor. It has about 3,000 units of public housing but several homeowners, including Barry, have settled in the community, attracted by the area's large detached brick houses.

"I've lived here since 1948," said Ward 7 resident James W. Price. "It used to be that people didn't care about anything around here. This building is the best idea around here in a long time."