The Metro board voted last week to award a $23,275,000 construction contract for the Bethesda Metro Station to a joint venture of Fruin-Colnon Corporation, Horn Construction Company, Inc., and L and W Concrete, Inc.

The subway station, which will be 780 feet long, will be built under Wisconsin Avenue at East-West Highway in Bethesda. The length of the station is the equivalent of a 70-story building, according to Cody Pfanstiehl, director of community services for Metro.

Construction is scheduled to begin in mid-April and the station is expected to be completed in about three years, Pfanstiehl said.

Along with construction of the station, the contract includes construction of the station entrance, an elevator for handicapped passengers, an electrical substation and chiller plant for air conditioning and an area for buses.

The joint bid was $1,642,750 less than the Washington Metropolitan Transit Authority's estimate of $24,917,750. Seven bids were received by the board, ranging from the joint bid of $23,275,000 to a high of $25,366,000.

The Fruin-Colnon Corporation, of St. Louis, Mo., sponsor of the joint venture, has been in business for more than 100 years, according to Pfanstiehl. The corporation also was awarded a Metro contract of $12,977,000 in January 1974, for construction of an above-ground subway route just north of the Stadium-Armory station in the District on the New Carrollton route. That project was completed last year.

Horn Construction Company, of Merrick, N.Y., has been in business for 33 years and is experienced in heavy construction and tunnel construction.

L and W Concrete, Inc., of Columbia, Md., is a minority contractor recently organized and incorporated under its present name. Doing business as N and W Concrete Floor Company, the same management has performed work for the General Services Administration, the Bethlehem Steel Company and the State of Maryland, among others.