About 180 bus routes will be changed Sept. 4 as Metro continues its realignment of the bus system to feed the subway. Several routes are being eliminated and others are being added.

Most of the changes Sept. 4 affect the routes of the old AB&W Transit Co. - those connecting Alexandria, south Arlington and southern Fairfax County with Washington across the 14th Street and Memorial Bridges.

Generally, there will be no direct bus service from those sections of Virginia to Farragut Square, but buses will continue to operate regularly to Federal Triangle and the Southwest Mall.

The route for some inbound Federal Triangle buses will change. Once those buses cross the 14th Street Bridge, they will turn east on Independence Avenue to 7th Street NW, north on 7th Street to Constitution Avenue, and West on Constitution Avenue to the terminal on 10th Street between Constitution and Pennsylvania Avenues.

Some changes are scheduled for District of Columbia routes. New service will be added between Mount Pleasant and the Kennedy Center. Another new route will serve the Washington Hospital Center, Veterans Administration Hosptial and Brentwood Village.

Several routes that connect the new downtown on K Street with the old downtown on F and G Streets will be terminated at Metro subway stations during subway hours, but through service will continue at all times on other routes.

Service changes are scheduled on the Benning Road bus routes and on some other routes serving eastern and southern Washington.

Although the changes technically take place Sept. 4, the first heavy impact will be felt Tuesday, Sept. 6, the day after Labor Day.

Many of the bus routes will continue in their present status when the subway is not operating; many other routes will operate only during rush hours. Subway operating hours are on weekdays only from 6 a.m. to 8 p.m. Rush-hour service is provided and higher rush-hour fares are charged from 6 a.m. to 9:30 a.m. and from 3 p.m. to 6:30 p.m. weekdays.

New timetables and more specific bus route information than is listed here can be obtained from drivers on the routes affected and at Metro Headquarters, 600 5th St. NW.

Following is a route-by-route listing of the scheduled changes. If the route is not listed, no changes are scheduled.