A recent decision by the D.C. Court of Appeals has given new legal ammunition to citizens opposing the redevelopment of the Georgetown waterfront into a mintown of hotels, elegant shops, office buildings and luxury apartments.

After almost three years of litigation the Citizens Association of Georgetown and two other civic groups, appeared to have lost their battle last month against the city and developers when a D.C. Superior Court judge cleared the way for new construction on the waterfront.

Now, the appeals court decision, which involved a Capitol Hill rezoning case, is expected to be a key issue at a hearing in Superior Court next week during which the citizens will ask Judge Sylvia bacon to halt waterfront construction until the appeals court has considered their case.

On Nov. 2, Judge Bacon upheld the city zoning commission's authority to rezone the waterfront area in the absence of a comprehensive zoning plan for the whole city.

The citizens groups had argued in their suit that the city was bound by a set of land-use objectives set down by the National Capital Planning Commission in 1968 until the city developed a comprehensive plan.

In her opinion, Judge Bacon said that, with the implementation of home rule for the District of Columbia, the city was not bound by the NCPC's 1968 planning document. Rather, she said, it was the intent of Congress that the city have the right to zone as it sees fit - even without comprehensive plan.

Last week, however, in the Capitol Hill case, the D.C. Court of Appeals said the city's zoning commission must give "substantial weight and respect" to the NCPC plan, unless there is a strong basis for interpreting it differently.

The appeals court also cited language in the 1973 Home Rule Act that said zoning changes "shall not be inconsistent with the comprehensive plan for the National Capitol." Presuming that the appeals court, in the Capitol Hill case, was referring to the 1968 plan, the Georgetown rezoning was clearly inconsistent with that plan, said Bruce Terris, a lawyer who represents the citizen's group.

In court papers filed yesterday in the Georgetown case, the city argued that the zoning commission did accord "substantial weight and respect" to the NCPC plan, and thus met the test set down by the appeals court in the Capitol Hill case.

"Due to the unique nature of the Georgetown waterfront," the city argued, the zoning commission "had a rational basis for a somewhat different interpretation of what the (citizens) contend was the NCPC interpretation of the comprehensive plan."

The city contended that, before the 1974 rezoning, the zoning commission gave substantial consideration to testimony from NCPC consultants.

"Nowhere in the record did the NCPC say that the only type of development that would not be inconsistent with the comprehensive plan" would be the low density level that the citizen's group maintains is the only level consistent with the NCPC plan. the city contended.

The city urged Judge Bacon to deny the citizen's request for a court order halting construction pending the outcome of the appeal of her order, saying that otherwise "it will be a very long time before persons will feel secure in investing in the development of the waterfront..."