The Dublin Docklands Development Authority has rejected claims that its plans to create an underwater stage in the financial services quarter are an act of vandalism.
The authority has started infilling George's Dock with rubble to create a "unique event platform" for live music, theatre and even an ice rink.
When required, the platform will be accessed by lowering the water level.
The dock will still hold water when the work is completed, but it will be much shallower.
However, one local resident says the work will destroy the dock forever and ruin local businesses.
Mr Stephen Wallace says it will also reduce the adjoining Inner Dock, "the jewel of the International Financial Services Centre" to a "green algae cesspit".
"The insane reasoning behind this is said to be that the naughty lads of the area swim in the dock in the summer," Mr Wallace says.
However, the DDDA says it needs to create a solid floor to George's Dock to allow for the erection of a stage from time to time. When not in use, the dock will appear exactly as before, as the stage will be covered by water.
Fountains and water spouts will be installed to maintain the water quality and general amenity, the authority says.
The water level can be lowered when the stage is required for use.
As part of "extensive upgrading" of the dock, improved lighting, new seating and handrails will be installed to increase use and enjoyment of the amenity.
A retaining wall is also being constructed between George's Dock and the Inner Dock to allow water levels to be controlled and to permit separate drainage of each of the docks.
"This is an essential upgrade so that periodic maintenance work can be carried out in both basins, when necessary," says Ms Loretta Lambkin of the DDDA.
Ms Lambkin says the upgrade of the dock demonstrates the authority's continued commitment to developing a "world-class physical environment" in the Dublin Docklands area.
However, Mr Wallace remains unconvinced by assurances from the DDDA.
He wants the authority to "cease this insanity immediately and undo the damage already done".
Last month, the DDDA reported that 11,300 new jobs had been created in the area over the past three years, most of them in the high-tech business and financial services sector.
