The D.C. Water and Sewer Authority is conducting its annual program to flush water mains throughout the city, a procedure designed to remove sediment and improve water quality.

From 7:30 a.m. to 3:30 p.m. Monday through Friday, WASA crews are opening fire hydrants in designated neighborhoods and flushing water.

The water supply to customers is not shut off during the flushing.

Customers might notice some water discoloration. If that happens, WASA recommends that residents open the cold water tap and allow the water to flow slowly until it is clear.

Customers should not run hot water or do laundry during the flushing. If the hot water becomes discolored, WASA recommends flushing the hot water tank by opening the valve at the bottom of the tank.

The flushing program will continue through November.

These neighborhoods, with boundary streets, are scheduled for flushing the week starting Sunday, according to information provided by WASA:

* ANC 4C (work area in Northwest, bounded by Ingraham Street, Illinois Avenue, Buchanan Street and Georgia Avenue).

* ANC 4C (work area in Northwest, bounded by Kennedy Street, 5th Street, Emerson Street and Illinois Avenue).

* ANC 4C (work area in Northwest, bounded by Missouri Avenue, 3rd Street, Gallatin Street and 5th Street).

* ANC 6B(work area in Southeast, bounded by E Street, 11th Street, M Street and South Capitol Street).

* ANC 6D (work area bounded by M Street SW, First Street SE, V Street SW and First Street SW).

* ANC 7D (work area in Northeast, bounded by Nannie Helen Burroughs Avenue, 50th Street, East Capitol Street and 47th Street).

* ANC 7C (work area in Northeast, bounded by Dix Street, 57th Street, East Capitol Street and 50th Street).

* ANC 7B (work area in Southeast, bounded by Fort Dupont Street, Southern Avenue, Pennsylvania Avenue and Alabama Avenue).

* ANC 7B (work area in Southeast, bounded by Massachusetts Avenue, 39th Street, Pennsylvania Avenue and 33rd Street).

* ANC 1C (work area in Northwest, bounded by Irving Street, Georgia Avenue, Euclid Street and Adams Mill Road).

* ANC 1B (work area in Northwest, bounded by Kenyon Street, Georgia Avenue, Euclid Street and 13th Street).

* ANC 3B (work area in Northwest, bounded by R Street, 28th Street, Q Street and 31st Street).

* ANC 4C (work area in Northwest, bounded by Colorado Avenue, 17th Street, Quincy Street and 28th Place).

* ANC 5C (work area in Northeast, bounded by Michigan Avenue, 3rd Street, R Street and 1st Street.)

* ANC 5C (work area in Northeast, bounded by Taylor Street, 12th Street, Perry Place and 6th Street).

* ANC 7C (work area in Northeast, bounded by Meade Street, 50th Street, Sheriff Road and Minnesota Avenue).

* ANC 7C (work area in Northeast, bounded by Eastern Avenue, Minnesota Avenue, Polk Street and Anacostia Avenue).

* ANC 5B (work area in Northeast, bounded by Mount Olivet Road, Trinidad Avenue, Florida Avenue and West Virginia Avenue).

* ANC 5B (work area in Northeast, bounded by Mount Olivet Road, Bladensburg Road, Florida Avenue and Trinidad Avenue).

* ANC 7A (work area bounded by Clay Place NE, Anacostia Avenue SE, F Street SE and Anacostia Freeway).

For information, call the WASA Water Quality Office, 202-612-3440, 8 a.m.- 4 p.m. In an emergency, call WASA's 24-hour hotline, 202-612-3400.