The population of Donabate and Portrane in north Co Dublin could more than treble within a decade if a major rezoning motion is passed this week.
Almost 400 acres of land surrounding Donabate village is up for rezoning for residential development under the motion to vary the 1999 Fingal County Council Development Plan.
Opponents said the move is "too much, too fast" and will increase the population from 7,500 to 26,000. Such a rise, they said, is unsustainable in an area with no secondary school and an "overloaded" infrastructure.
Fingal County Council said it wants to update the existing "patchwork" of zonings by "consolidating" the village centre in Donabate. While existing growth is limited by the capacity of the local sewage treatment plant, "this doesn't mean we shouldn't look at the sensible development of the plan", said Mr David O'Connor, head of services at the council.
Mr Jim O'Donohoe, planning officer with Donabate parish council, said the rezoning has "all the hallmarks of being rushed through. All the other development plans put together don't add up to this. So why is it happening so fast?"
He said enough land had already been rezoned for 6,500 new residents. "There is certainly no bottleneck stopping development through lack of land."
He pointed out that the Northern Area Health Board may seek to rezone some of its land at St Ita's Hospital, Portrane, for sale to property developers, thereby creating a possible 2,900 new dwellings. "This is for an area in which we don't even have footpaths connecting houses to the village centre," said Mr O'Donohoe. Labour TD, Mr Seán Ryan, said he will oppose the motion because it "goes against" the strategic planning guidelines for Dublin. Even with the present levels of population, local commuters can't get a seat on the trains, and it will take years to upgrade the service.
The rezoning proposal was initiated last May through a 12-6 vote of the county council. Some 300 submissions have since been made, most of them critical of the plan. The parish council claimed the proposal clashed with advice from independent consultants on the protection of areas of extreme or high sensitivity.
Most Fianna Fáil and Fine Gael councillors are expected to support Wednesday's motion, although opponents are hopeful that last-minute lobbying could swing the vote in their favour.
Local residents plan to demonstrate outside the council chamber during the vote.
Mr O'Donohoe said "everyone wins" if the decision is deferred until the review of the plan is completed.