Replacing the footbridges to the islands overlooking Great Falls should be top priority for the National Park Service, according to local residents and representatives of planning agencies and civic groups.

Proposed development plans -- including footbridge replacement -- for the C & O Canal area near Great Falls have been discussed by these planning agencies and civic groups at meetings during the past several weeks.

Most speakers at the meetings opposed building parking lots, picnic areas and a bike trail in the mining strip beside Great Falls, where Union soldiers discovered gold in the 1860s. Also opposed were plans to expand parking and Park Service maintenance garages and yards at Great Falls, and to build additional boardwalks along sections of the towpath damaged during tropical storm Agnes in 1972.

Besides replacement of footbridges, there is strong support for additional restoration of the canal, lock houses and the historic Great Falls tavern, and for enlargement of existing parking lots near Angler's Inn east of Great Falls and Swain's Lock to the west.

Proposals for the canal and park land around Great Falls are made in a 112-page study of "alternatives" for developing the Great Falls area. Park Service officials said they will accept comments on the proposals until Jan. 4. They expect to produce a final development plan sometime this spring.

Few changes are expected to be funded or made before 1982 or 1983 at the earliest, said C & O Canal Supt. William Failor. The cost of alternatives proposed this summer would range from $872,000 to $2.2 million. But none of the package plans has been supported by any group.

Both the National Capital Planning Commission (NCPC) and the Montgomery Planning Board last week approved segmets of the Park Service plans. NCPC endorsed additional restoration of the 1832 Great Falls tavern and nearby Lock House No. 16, built in 1837. The commission also approved restoration of the towpath and footbridges to allow visitors to view the falls themselves, now almost invisible from the Maryland side of the Potomac River.

The federal planning agency also urged construction of stables for horses belonging to the U.S. Park Police mounted division. But it opposed expansion of the existing 575-car parking lot near the tavern, wooden boardwalks over damaged sections of the towpath, a new visitors' center or use of the tavern as a restaurant.

The Montgomery Planning Board, however, specifically urged that the historic tavern be returned to use as a tavern -- much as the city of Alexandria has made its historic Gadsby's Tavern a working restaurant. The county agency also urged that the present food stand be removed, that no new buildings be constructed around the tavern and that the gold-mining strip not be developed.

"Probably the most important improvement that could be provided is replacement of the bridges to Olmstead and Falls Islands" destroyed in 1972, the county planning staff said in its report on Great Falls.

The 500-member C & O Canal Association, the group formed in the 1950s by former Supreme Court justice William O. Douglas and others to save the canal from being bulldozed for a highway, also has urged rebuilding of the bridges. In addition, the organization opposes additional parking near the tavern and development in the gold-mining strip, and urged that the towpath be restored and existing boardwalks removed. It also favors having Park Police stables built at Great Falls but is opposed to use of the tavern as a tavern, said association president Nancy Long.

The C & O Canal citizens' advisory board, created when Congress made the canal a national historical park in 1971, expects to discuss the Park Service plans when it meets Saturday. The board, however, already has urged the Park Service to separate reconstruction of the footbridges from the rest of the Great Falls proposals, and to rebuild the bridges as soon as possible.

More than 100 persons attended public hearings on Great Falls on Nov. 1 and Dec. 1. Most of those who spoke took positions similar to the planning and citizens' agencies.