Locals in north County Dublin claim a proposed new halting site would put their homes at risk because it is a floodplain.
Members of the travelling community are to be relocated to Coolquay from DAA-owned land 12km away because the authority needs the land back for the airport's new runway.
Fingal County Council says it carried out a risk assessment of the proposed development, including flooding concerns.
But local businessman, Joe Finnegan, says they rely on that field for drainage.
"We know this part around us quite well because we're looking at it when it's raining," he said.
"When I see water in the fields to the rear of me edging out a couple of metres I say 'we stand a chance of getting wet here'.
"We might start to think of moving our machines, switching off the power, that kind of thing."