The Shannon Regional Fisheries Board (ShRFB) and the Inland Waterways Association (IWA) have expressed concern at the proposal by Dublin City Council to abstract water from Lough Ree on the Shannon to supply the water needs of the greater Dublin area.
"We are concerned about the environmental situation and the effect that this will have on the ecology and on navigation on the Shannon," said Colin Becker, project manager of the IWA.
The Irish Timesreported yesterday that local farmers and businessmen were unhappy with the council's proposed plan to meet increasing demand for water in the capital from the Shannon waterways.
The IWA and the ShRFB said they were were also seeking clarification from the council on the overall effects of the proposal.
Mr Becker said that many questions remained unanswered.
"We need to know what the effect of the abstractions on the waterways will be when the water levels are low. The proposed maximum abstraction levels are 2 per cent of average flows at Lough Derg, but we don't know whether that will change at times of low water levels," he said.
Eamon Cusack, chief executive officer of ShRFB, also expressed concern about the implications of the proposal at times of low water levels. "We've been involved in the consultation process and the board has concerns, particularly over abstraction during periods of low water levels, especially if there is evidence to show that global warming will effect water levels."
Mr Cusack said that reduced water levels on the river would deplete the fish population of the Shannon and adversely affect the ecology of the region because effluent from the land would be less diluted in a reduced body of water.
The IWA is also concerned about the effects of abstractions from Lough Ree on the entire river Shannon.
Mr Becker suggested that abstractions from lower down the river, at Lough Derg, would have a less negative effect on the waterways.
Mr Becker also expressed concerns about the transferral of natural resources from one region to another. "We don't want to rob one area to supply another area," he said.
However, Labour's spokesman on the environment Eamon Gilmore TD said water supply was not a regional issue.
"Water planning needs to be looked at on a national basis. While I sympathise with people in the region, I think that the issue of water is a national one. You can't say that water belongs to one part of the country," he said.
Mr Gilmore said the issue of water supply needed to be addressed strategically.
He added that this should be done with regard to climate change and also with regard to the rising demand for water.
"In this country so much gets done after the horse has bolted. We retrofit everything," he said.
"Houses are built before adequate facilities and social services are put in place. The water issue is part of that same problem. We need to plan first."