The Prince George's County Council this week approved amendments to the 10-year water and sewer plan that could allow at least 3,500 new single-family homes and townhouses to be built in the county in the next two years.

According to several area developers and landowners, this could mean new construction starts on at least 1,000 homes by late spring or early summer in clustered areas around the county.

The action came as the planning arm of the county government released its citizens advisory committee proposals on new growth patterns within the county, citing water and sewer limitations as a major constraint on the growth.

The growth proposals, called the General Plan, forecast significant population increases in the greater Laurel area in the north, the Bowie New Town in the west, and the proposed Mattawoman New Town in the southern end of the county.

While the water and sewer amendments allow for residential and industrial growth throughout the county, the council's action will permit significant large housing developments near these same three areas.

These will include Tobacco Knolls, at Rte. 301 and 5, Mariboro Meadows near Upper Mariboro, and Hillmeade near old Bowie. The developments eventually will bring 728 homes to those areas. The Largo area also would be significantly developed through the building of Largo Knolls, Mitchellville, and a 400-home development near the intersection of George Palmer Highway and Rte. 50

"All of this growth isn't necessarily going to happen," said Donna Bigley, council aide on the water and sewer issue. "There are quite a few filter mechanisms to reduce these maximum levels of development. The plan sets an outer limit, and actual development is reduced through the sewer allocation policies, through building permits, through financing problems, and ultimately, through the market place."

The 3,500 residential units join 19,000 other potential housing starts eligible for water and sewer service in the county. One of the reasons cited for lack of development of those houses is the slowed growth rate since the mid-1960's, according to Bigley.

"But the fresher the development, the better. These new amendments stand a decent chance of development," Bigley said.

William Beckett, a trustee for 173 acres at the George Palmer interchante on Rte. 50, said "The market is softer than it has been in the past." But developers of the land within the year on 120 of the 400 homes proposed for the site, he said. "They wouldn't go into it if they didn't think there was a market," Beckett said.

Industrial development is also affected by the new water and sewer amendments. Several proposals were moved ahead into a classification permitting immediate water and sewer service.

A $10 to $15 million industial park for 34 acres near Pennsyvania Avenur and the Beltway, according to Russell Shipley, attorney for landowner Kenneth Harris.

Shipley said that Harris had been talking with Quality Moving and Stornage, American Motors, District Hotel Supply, and Briggs & Company about moving to the proposed industrial park.

"The cost benefits to the county are magnificently on the plus side," Shipley said at a public hearing on the amendment this week.

"This could bring in $200,000 in real estate taxes a year," he said.

Another commercial project, the North Springhill Lake Commercial project near Greenbelt, is expected to add five 100,000 square-foot buildings and a major hotel to the area. The project has already received a sewer allocation from the council even though the plan was not legally eligible for water and sewer service until 1988. The council amendment on the project allows construction to begin as soon as a road system is developed.

All the development proposals raised the issue of potential over-growth in the county. In a draft letter to County Executive Winfield M. Kelly, the council expressed concern that "residential land immediately (eligible for water and sewer service) was much more than double the amount expected to develop within the next two years. More property is shown for future service than can be served."

John McDonough, an aide to Kelly, said that a study of allocation policies in the five sewage treatment areas, coupled with next year's look at the water and sewer plan, would help the council spot any overdevelopment trouble areas.

As the council members breathed a collective sigh of relief that the water and sewer amendments passed, membr Francis B. Francois bid a verbal adieu to the legislation.

"This may not be perfect, but it represents a compromise for all of us. It moves Prince George's County further ahead in the growth process. It is a good plan," he said.