Low-income District residents face severe obstacles in commuting to blue-collar jobs in the suburbs because of inadequate public transportation, a new study by the Metropolitan Washington Council of Governments has concluded.

Trips by bus or subway from Southeast and Northeast Washington to suburban areas where jobs are available usually take more than an hour each way, the study found. In contrast, the report said, higher-income city residents can get to white-collar jobs by car much faster.

"Transit accessibility to suburban job sites is relatively poor," said the report, released after a year-long $50,000 computer analysis.

The findings underscore widespread concern among District and other local government officials about difficulties in matching unemployed D.C. residents with suburban jobs. In June, District Mayor Marion Barry launched a campaign to find work in the suburbs for jobless city residents.

According to the report, transportation poses a key problem for unemployed D.C. residents because most increases in jobs in recent years have occurred near the Capital Beltway and along highways outside the Beltway -- areas that are difficult to reach without a car.

"There just didn't seem to be adequate transportation," said David Cardwell, a COG planner who headed the study.

According to Metro officials, the transit service shortcomings have stemmed partly from delays in constructing the Green Line, which was planned to serve Anacostia and other low-income District areas. The Green Line is the only unopened route.

In addition, Metro officials said, bus service has been designed for suburban residents who work in the District rather than for city residents who have suburban jobs. A bus ride from the city to the suburbs may take a long time because of traffic congestion and relatively long distances, they added.

In an interview, Cardwell cited several major employment centers in the suburbs that are relatively inaccessible by public transportation for residents of Southeast and Northeast Washington communities such as Anacostia, Benning Heights, Kingman Park and the New York Avenue corridor.

Seventy-three percent of the residents of these low-income neighborhoods would need more than an hour to get to work in Northern Virginia areas near Springfield where blue-collar jobs are available, Cardwell said.

Sixty-nine percent of these residents would have to spend more than an hour to reach blue-collar jobs in the College Park and Riverdale areas of Prince George's County, he said. Fifty-four percent would need more than an hour to get to the county's Ardwick and Ardmore communities.

The study found that unemployed D.C. residents faced even longer trips to employment centers in Montgomery County, such as Gaithersburg and Bethesda. However, Cardwell said, the study relied on 1980 data, compiled before the subway system extended the Red Line to Shady Grove near Gaithersburg.

The rail extension probably has shortened the time of trips to Montgomery for some low-income D.C. residents, Cardwell said, but he added that Metro fares may pose a further problem. A rush-hour trip by subway and bus between the District and Gaithersburg may cost more than $2 each way.

The report recommended measures to improve transportation to the suburbs, including expanded bus service, more van and car pools, government-financed transit subsidies for unemployed residents and reduced rush hour fares for rail trips to suburban employment centers.

Some steps have been taken to bolster transportation and others are under review, according to District and Metro officials.

Ed Meyers, planning director for the D.C. Department of Employment Services, said the city has started offering free bus tokens and subway Farecards to unemployed residents who find jobs in the suburbs. Applicants may receive $8 a week in tokens or $10.50 a week in Farecards for 10 weeks.

More than 100 unemployed residents have been given help in finding adequate transportation to get to jobs since the program started in June, Meyers said. The city has set up van services and offered advice on transit routes.

Robert A. Pickett, assistant planning director for the Metro system, said the transit authority is considering improvements in service to help D.C. residents get to jobs in the suburbs, including more bus service in outlying areas at rush hours.