Most Washingtonians are aware of local new towns called Columbia, Reston and Montgomery Village.

Many can also identify Dale City, Crofton, St. Charles, Northampton, Sterling Park and Rossmoor. These planned communities, in existence for a decade or more, have more than the usual subdivision amenities.

Then there is Lake Ridge, under development for 10 years on 3,000 wooded and undulating acres on the south side of the Occoquan Reservoir, west of I-95 in Prince William County. Several miles closer to Washington than neighboring Dale City, Lake Ridge now has about 8,000 residents in 2,600 houses, nearly half built by the Edward R. Carr firm. Prices of Lake Ridge houses, which include cluster dwellings, town houses and detached homes, range from the $30,000s to nearly $100,000, the latter for houses near the water.

Ridge Development Corp., a subsidiary of Weaver Bros., has plowed some $10 million into roads and other facilities since the land was purchased in 1966. About 400 houses will be started there this year, 100 more than last year, but far fewer than the record 625 begun there in 1971. That was a big year in new housing, locally and natinally.

Since then, a slower development pace has been dictated by Prince William County, which, like other area jurisdictions, has been concerned about its capacity for increased sewage disposal. Lake Ridge's developers now feel they can begin 500 to 600 houses there a year.

Lake Ridge, site of the new Woodbridge High School and a small shopping center, benefits considerably from its location on the 1,700-acre reservoir, which has 16 miles of wooded shoreline and a feeder stream called Hooes Run, where some of the community's more expensive homes have been built.

Boating and fishing are big with Lake Ridge residents.But they must forego power boating on the reservoir, which is Northern Virginia's major source of water.

[A recent, three-month study by the Environmental Protection Agency showed that chloroform in the reservoir's water - created when chlorine reacts with nutrients in the water - exceeds the highest safety threshold suggested by the Environmental Protection Agency. Although choloform in large quantities is suspected of causing cancer, a spokesman for the state health department said he "didn't think there is anything to be made of (the Occoquan levels) at this time." The state has asked the EPA for technical assistance in dealing with the problem.]

Lake Ridge is entered from Davis Ford Road, off Route 123, into Old Bridge Road, which almost bisects the community. Two churches are in place, as are swimming pools, recreation areas and a community center. There's also a parking lot to serve some of the many commuters who use scheduled bus service into Washington and Northern Virginia.

Included in the Lake Ridge parameter but not part of the community is the small private Woodbridge Airport, which at least puts Lake Ridge one up on other area communities.

In addition to the Carr firm, which builds inexpensive cluster houses as well as higher-priced, detached houses there, Lake Ridge builders include Sorensen Construction Corp., Kettler Brothers and Pinewood Development, Carr plans to offer some new contemporary houses near the lake later this year.

The Sorensen firm is doing both single-family houses and town houses now and soon will offer some new energy-saving models. R. Michael Sorensen, 28 and a vice president of the firm headed by his father, Lester Sorensen, lives with his family in a Sorensen-built house in Lake Ridge.

"We live here because we like it," he says.

New to Lake Ridge but widely known in this area as a builder and the developer of the Gaithersburg's Montgomery Village, the Kettler firm started building $50,000-range townhouses in Lake Ridge last year. The site is near the new high school, which boasts famed Michigan footballer Russell Davis as one of its graduates. The Kettlers say they have had "good results" at Lake Ridge and plan to build more houses there.

A Kettler executive noted that Lake Ridge is easier to find, now that new road signs are up. He also suggested that paths around the lake would be a nice addition to the community.

Pinewood Development, which began building "fourplex" units in Lake Ridge, has shifted to town houses with individual titles and finds the market better for that product. Harold Sampson, president of the firm, said that the community offers many environmental pluses to residents. But he said he wished there were more single-house lots available for builders because of the growing market for that type of house today.

Almost all Lake Ridge families belong to the community's parks and recreation association. They pay an annual fee for their share of the non-profit operation of recreation and community facilities, which have a full-time manager. Altogether, about 600 of Lake Ridge's 3,000 acres are preserved as open space.

Development at Lake Ridge is directed by Martin R. West Jr., Donald G. West and James E. MIller, who are also top executives at Weaver Bros., a Washington mortgage banking and real estate brokerage company. Donald West succeeded the late Edward K. Jones, a Weaver executive and an original planner developer of Lake Ridge in the days when it was known as Ridgefield.

In charge on a day-to-day basis at Lake Ridge are Kenneth Thompson and Alan Inabinet, assistant vice presidents of the Weaver firm, who are responsible for land development and marketing at the new community. They hope to build a commuter parking lot there this year as well as a small office building for professional people. Thompson does not rule out the development of garden apartments in the future but said high-rise construction is far less likely.

"We are trying to create a mix in architecture and price and to provide a market that will permit people and families of varying incomes to find homes to suit their needs," Thompson said, as Inabinet nodded approval.

Meanwhile, the developers of Lake Ridge, tired of being "the other guys" of area new town development, are trying to establish a slightly higher profile for their community.