Though the construction work will cause some road lane closures and water supply interruptions, disruption to residents is expected to be minimal, said Chuck Brown, a spokesman for the Washington Suburban Sanitary Commission, which is heading the replacements.

The Montgomery Village and Washington Grove replacements are part of WSSC's $180 million project beginning this spring to replace about 150 miles of "older cast iron" pipes with "ductile iron" pipes over the next six years throughout Montgomery and Prince George's counties, according to the WSSC.

The new pipes are lined with cement mortar, which will protect them from corrosion.

In Montgomery Village, workers began replacing the existing pipes, which were installed in the 1960s, on Rhodes Way at the end of March. They will also work on Oxcart Place, Napoleon Way, Kobe Way, Diary Road, Brook Grove Court and Roman Way between now and spring 2006.

Workers will dig new trenches in which to lay the 3 to 4 inch-wide pipes. Water supply to residents should only be interrupted once for three to four hours when the new pipes have been set and workers make the switch from the old pipes.

The project will probably pause in the winter when weather conditions make it too difficult to work, Brown said.

In Washington Grove, where the pipes date to the 1920s, work began on Brown Street in the beginning of March. Pipes will also be replaced on Chestnut Road, Grove Road, Pine Avenue, Pine Road, Maple Avenue, and Maple Road. The project is expected to finish in the fall, Brown said.

Because workers will have to break the existing pipes and lay the new 8 to 10 inch-wide pipes in their place, WSSC set up temporary water mains above ground.

There will be some single-lane closures while workers operate from 7 a.m. to 5:30 p.m. on Mondays through Thursdays.

In Washington Grove, where all the roads are narrow and some of the roads are walkways, Brown expects the traffic disruptions to be minor.

Jim Fletcher, Washington Grove's maintenance manager, said roads have mostly been closed after school buses drive through in the morning and before they pass in the afternoon.

"When you have a project of this type, there are always people who have problems, but it's gone smoothly," Fletcher said. "... For the most part residents have been able to access their homes."

Sharon Goldberg, director of communications for the Montgomery Village Foundation, said the Whetstone community manager worked with WSSC in planning the work, and that "everything is on schedule. The residents have been notified, and no one's complained."

Residents will not feel any difference in their water supply once the project is complete, Brown said, and water pressure should be the same.