Washington-area construction continues unabated.

In October, new construction contracts totaled $570.4 million throughout the Washington region, up 50 percent over the same month last year, according to the latest report of the F. W. Dodge Division of McGraw-Hill Information Systems Co. Residential construction was up 60 percent; nonresidential, 42 percent.

For the year, building contracts total $4.5 billion in the Washington area, a 9 percent increase over the first 10 months of 1984.

NVLand, a McLean-based development company, has purchased 277 acres of prime residential land along the Potomac River in northwestern Fairfax County and plans to build 85 homes there to be priced between $300,000 and $1 million.

The land extends from the end of the present Falcon Ridge development east of Seneca Road to the Potomac. Most of the 14 lots overlooking the river will be developed as 10-acre estates, according to NVLand officials.

NVLand President William Moran said his company has "a contract" to buy the land from Moeller Steamship Co. of New York, which has owned the site since 1953 when it was "purchased as an investment." The sale price was not disclosed.

The site was approved for a cluster development for 135 single-family detached homes in the late 1970s after a bitter court fight between Fairfax County and the developer. Moran said his company is "redesigning the 277 acres into only 85 lots.

"It's very apparent in looking at Great Falls that there is no new cluster development north of the Georgetown Pike," Moran said. He said his company will go along with that trend, which he described as "the desire of the residents of Great Falls."

Estelle Holley, president of the Great Falls Civic Association, said she is pleased by NVLand's intention to abandon cluster development. She said building only 85 homes "will put an end to rumors and speculation" about the future of the property. Holley and other Great Falls residents said they plan to work closely with developers to make sure that horse trails are provided and that natural features of the tract are preserved.

Moran said developers will give 80 acres of land fronting on the Potomac River to the Fairfax County Park Authority to incorporate into the existing park system along the river banks.

J. A. Loveless Co. has a new appeal to make to potential tenants for its Point West Plaza office building now under construction in the Tysons Corner area.

Tenants will have the benefit of a par-3 golf course incorporated with jogging facilities among the building's amenities. Point West Plaza is being built in the Westwood office park beneath the shadow of the 23-story Sheraton Hotel now under construction.

The 145,000-square-foot building will be finished next summer, according to Joe Moravec, president of the Washington office of Legatt McCall & Werner, an industrial and commercial leasing and brokerage firm.

The Maryland Department of Economic and Community Development is providing low-interest mortgage loans to buyers of 34 town houses in the Oliver-Johnston Square II development in Baltimore. The low-interest mortgages are available to qualified buyers on a first-come, first-served basis.

To qualify under the program, an individual may earn up to $28,000 a year. A household with two or more people may have an annual income of up to $33,000.

The 1,200-square-foot town houses -- with three bedrooms, 1 1/2 bathrooms and central air -- will sell for $37,200. The development is bounded by Harford Avenue, Biddle, Chase and Ensor streets in East Baltimore. The developer, Van Dyke Building Corp., will buy down the interest to an initial rate of 8.4 percent, the agency said.

The Suburban Maryland Building Industry Association has scheduled a free course on how to buy a home, from 7 to 9 p.m. next Tuesday, at the Ramada Inn, 4050 Powder Mill Rd., Beltsville. For information and reservations, call 572-5900.

The Montgomery County Office of Landlord-Tenant Affairs has produced a new free publication called "Landlords and Tenants: Their Rights and Obligations," available in the landlord-tenant agency's fifth-floor office at the Stella B. Werner County Council Office Building, 101 Maryland Ave., Rockville.

IN THE BUSINESS . . . Kathleen A. O'Brien, an assistant vice president with Rubloff Inc., has been named associate broker of the year by the Washington Board of Realtors . . . Melvin Colton, executive vice president of the Arlington firm of Ratcliffe, Cali & Co., has been elected 1986 president of the Washington-area chapter of the American Institute of Real Estate Appraisers . . . Nancy L. Gossard, sales manager of Long & Foster's Odenton office, has been elected president of the Maryland state chapter of the Women's Council of Realtors. Queenita A. Gaskins of Long & Foster's Camp Springs office has been elected president of the Prince George's chapter of the same group. . . Stanley Martin Cos. reports that the 5,000th family has moved into one its homes since the company started building in Northern Virginia and suburban Maryland in 1966 . . . Carr Properties has purchased Magnolia Commons, a 197-unit rental property in Arlington, and has started a $3 million renovation . . . Construction has started on the Wells Cove Development Co.'s 230-unit Oyster Cove residential project near Grasonville on Maryland's Eastern Shore . . . Old Colony Inn in Alexandria has started a $12 million, 100-room expansion of its 223-room facility . . . Trainees at the Institute for the Construction Trades, a nonprofit subsidiary of the Northern Virginia Builders Association, have completed their first house, at 11618 Mohican Rd. in Lake Ridge. Proceeds from the sale of the house, listed at $139,500, will be used for more training and overhead costs . . . Mortgage loan delinquencies at U.S. savings institutions declined in September, with residential notes 60 days or more delinquent down from 1.76 percent in August to 1.64 percent, the U.S. League of Savings Institutions reports . . . Graham Landscape Architecture of Annapolis, in conjunction with Walmsley & Co. Ltd. of New York, was the first-place, $10,000 winner of a design competition to revitalize Druid Hill Park in Baltimore . . . Porten Sullivan Corp., a large Washington-area home builder, has agreed to sell all its shares to International American Homes Inc. for $16 million . . . Mason Hirst Cos. has sold two buildings at the Lake Fairfax Business Center in Reston totaling more than 100,000 square feet to the Federal Home Loan Mortgage Corp. (Freddie Mac) . . . Donohoe Construction Co. has started construction of a $15 million Holiday Inn at 4610 N. Fairfax Dr. in Arlington . . . The Federal National Mortgage Association (Fannie Mae) is offering 33 homes for sale in the Washington area that it has acquired through foreclosure.

PERSONNEL FILE . . . Mark Vogel Cos., a Washington developer, has named Charles F. Yetter as director of construction . . . Thomas C. Lewis has been named vice president/operations for Oxford Development Corp. Richard O. McKerr has been appointed vice president/acquisitions of Oxford National Properties Corp. . . . Raymond S. Olsen has been named vice president of JBG Properties Inc. . . . Thomas M. Joyce is now vice president and director of the commercial brokerage division of Shannon & Luchs . . . Thomas G. Owens has joined Spaulding & Slye's Washington office as vice president and brokerage manager.