In the biggest single expansion of Washington's residential permit parking program, the D.C. Department of Transportation has asked the City Council to ban commuter parking in 378 more city blocks.

The areas include the entire Dupont Circle neighborhood, the fringes of the American University campus, the Metrorail stations at Takoma, Brookland and Rhode Island Avenue and the Metrobus garage at 14th the Decatur streets NW.

If, as is almost certain, the request is approved by the council, the area covered by the commuter parking ban will be expanded by about 50 percent virtually overnight.

About 750 blocks now are covered by program. The largest areas are in or near Georgetown, Capitol Hill, Friendship Heights, Shepherd Park, Adams-Morgan and Kalorama.

Recently, the council voted to add 63 blocks on the fringes of some of these latter areas. The new restrictions on the 63 blocks will go into effect as sson as signs are erected, probably about June 5, city officials said.

Mayor Walter E. Washington asked for the addition of the 378 additional blocks in two letters forwarded to the council on May 3 and May 19. Under council procedures, the approval is almost automatic.

The permit parking program is designed to keep commuters from parking in residential neighborhoods near areas of heavy employment or commercial activity, or near transit stations. Residents of such areas have complained for years that they find it difficult to park near their own homes because of the commuters.

Residents of the restricted areas must buy a $5 annual sticker for each automobile, allowing it to be parked for extended periods. Cars belonging to outsiders may be parked only two hours.

Under city procedures, the residents of proposed parking-permit areas were required to sign petitions. Then the affected blocks were checked by Department of Transportation personnel to determine if a high proportion of parking spaces were actually occupied by commuter cars.

Neighborhood forums (informal public hearings) were held in each of the affected areas before D.C. Transportation Director Douglas N. Schneider Jr. sent his recommendations to the mayor.

When the council recently voted to add 63 blocks to the program, it also voted to remove one block where the ban had been put into effect previously. Residents of the block of 55th Street SE, just south of East Capitol Street, filed a petition seeking the removal.

"This ban was imposed by the City Council on the omeowning, taxpaying residents of the area without their prior knowledge," Catherine Allen, of 81 55th St. SE, the block chairman, said in the petition.

Following are the 63 blocks which will have restricted parking soon, as a result of the recent council vote:

Walter Reed NW area - 7th Street, 7400; 8th Street, 6900; 14th Street, 6600 and 7500; Hemlock Street, 700; Juniper Street, 800; Locust Road, 1400 and 1500; Morningside Drive, 7600; Northgate Road, 1400.

Capitol Hill NE - Acker Street, 600; 6th Street, 600; 10th Street, 300 and 500; 20th Street, 200; 21st Street, 200 and 400; Maryland Avenue, 1300.

Capitol Hill SE - C Street, 1000 and 1400; D Street, 1100; E Street, 1500.

Glover park NW - 35th Place, 2700; 36th Street, 2800; 37th Street, 2300 and 2400; Davis Street, 3500.

Foxhall Village NW - Hoban Road, 4500; MacArthur Boulevard, 4400.

Foggy Bottom NW - Snows Court, 0. (Until now, no parking has been permitted in Snows Court. The council action will allow parking but only under the permit program.)

Friendship Heights NW - Chevy Chase Parkway, 5100, 5200, 5400 and 5500; Harrison Street, 3800; Huntington Street, 3800; Jenifer Street, 3700; Livingston Street, 3700; Legation Street, 3600 and 3700; Morrison Street, 3700; Oliver Street, 3700; 38th Street, 5300.

Sheridan Kalorama NW - Argonne Place, 1600; Lanier Place, 1700; Ontario Road, 2700 and 2800; Decatur Place, 2300; 18th Street, 2800.