Lobster fishermen in Waterford and the environmental group Coastwatch have called on the Minister for the Marine to revoke Waterford Port Company's dredging licence after divers reported that the operation was damaging important shellfish spawning areas.
Fishermen, divers and members of Coastwatch have claimed that, since dredging started, a fine, dust-like coating of sand and spoil has appeared over a wide expanse of water stretching into the Hook Head Special Area of Conservation on one side of the estuary. They say it has also covered a submerged wreck at Brownstown Head on the other side.
The port company has denied that its dredging operations are causing the damage and suggested that the current spring tides may be responsible for whatever spoil is to be seen in the area.
The dredging licence to remove more than 500,000 tonnes of spoil from the estuary covers a three-month period, from July 31st to October 31st.
The operation proved to be controversial from the start when it coincided with a tidal experiment organised by Coastwatch.
It also coincided with a local environmental week and with the tagging and "v-notching" (a form of marking) of juvenile lobsters by the East Waterford Lobster Fishermen's Co-op.
The fishermen's v-notching is part of a seven-year stock conservation programme which the chairman of the co-op, Mr Trevour Simpson, said is now in danger of being wasted.
He said the lobster fishermen had bought and released into the area several thousand juvenile lobsters in a bid to increase stocks. But the important spawning grounds were located on either side of the approved dumping area for spoil from the dredging operation, jeopardising the project. "Either side of the dump site is the lobster grounds, so they are dumping right in the middle of the lobster grounds."
If the company insisted that the dredging and dumping were essential, he said, then the dumping should be done further out to sea. "They are saving pennies and we are paying the price - it must be stopped immediately."
Ms Karin Dubsky, of Coastwatch, also expressed disappointment that the dumping had not taken place further out. She called for the company's licence to be revoked.
"This is in an area which has an unusual wealth of spawning and juvenile grounds, as well as protected species and protected sites. The spoil plume is now half a mile into the Hook Head SAC."
She said the Department of the Marine, the fishermen and the local community should have been invited to have independent monitors on board the dredger and that the monitoring results should be published.
However, the chairman of the Port of Waterford, Mr Ben Gavin, said it was "stretching it a bit" to suggest that the dumping was causing damage to shellfish.
He said the dredging was necessary to keep the shipping channel open to Waterford and was carried out at this time of year for climactic conditions. Dredging had been done for 30 to 40 years and the shellfish did not seem to have suffered. He said the dumping was constantly monitored by the port company and he cast doubt on the possibility of a spoil plume reaching Brownstown Head.
It was more likely, he said, that the spoil was being generated by the spring tides. The operation had only about a week left to run.
A spokeswoman for the Department of the Marine said all scientific evidence suggested there would be no negative effects.
