The D.C. City Council cleared the way yesterday for the long-awaited arrival of cable television in Washington by voting to award a 15-year franchise to District Cablevision Inc., a local firm that would allow the Chesapeake & Potomac Telephone Co. to construct and own the transport lines for the cable system.

The council is expected to give final approval to the franchise in two weeks, after which it must then be signed by the mayor and clear a congressional review period. Once the bill becomes law, District Cablevision officials say, construction on the $130 million cable system would begin in 1985 and some homes in every section of the city would be wired for cable by early 1986.

The council's unanimous decision to award the franchise to District Cablevision comes after a lengthy and often bitter franchise contest that began in February when three companies -- District Cablevision, Capital City Cable and District Telecommunications Development Corp. -- submitted bids to build a state-of-the-art cable system.

But yesterday, despite the months of controversy, the franchise award was placed on the council's consent agenda and approved without any discussion.

"We must be the only city in the country to award a cable franchise on consent," said City Council member Betty Ann Kane (D-At Large), chairman of the council's cable committee. "But there really was no need for discussion because the council did such a good job in the public hearings and in negotiations."

"We're not at all surprised," said a spokesman for District Cablevision. "The council members who opposed DCI made their positions clear early in the process and they lost, and are now moving ahead on the perception that the majority will of the council should prevail."

As a result of difficulties that other large cities encountered when cable companies moved to scale back on their promises, the District negotiated a franchise agreement to ensure that District Cablevision delivers on its commitments within a reasonable time.

One provision of the agreement requires District Cablevision to put up a $2 million security fund during construction. The agreement also gives the firm one year to obtain adequate financing and 18 months to start construction, or the franchise will be terminated.

There remain, however, several items of unfinished cable business. One of the losing bidders, Capital City Cable, has filed an antitrust lawsuit in U.S. District Court alleging that District Cablevision and C&P Telephone illegally conspired to win the franchise.

Meanwhile, before construction can begin on the cable system, C&P Telephone must receive permission from the Federal Communications Commission to construct cable transport lines in an area for which it also provides telephone service. The city's negotiated agreement with District Cablevision includes a provision giving the firm until June 15 of next year to secure FCC approval.

Under the franchise agreement:

* District Cablevision would have four years to complete a system that would provide a 79-channel residential cable network and a separate institutional network.

* The cable firm would provide eight public access studios, one in each ward of the city, and financial commitments to public cable programming that would began at $200,000 a year and could reach more than $1 million a year.

* Once the system is complete, cable subscribers would be offered three levels of service ranging from an installation fee of $29.95 and a monthly rate of $1.95 for 35 channels, to an installation fee of $19.95 and a monthly rate of $12.95 for 79 channels.

* The system would offer at least 19 satellite services, such as Home Box Office and MTV. Subscribers would have to pay an additional monthly fee for some of the services.