The Right2Water group has said it supports water charges for users who are seen to use water wastefully.
The campaign group says it is a fair way to apply the so-called 'polluter pays' principle, enforced by the EU.
It has been giving evidence today at the Oireachtas committee on the future of water services.
Stevie Fitzpatrick from Right2Water says wasteful personal users, and wasteful commercial users, should all be charged.
"It's our viewpoint that the huge industrial wastage of water through water companies, distilleries, the pollution of rivers by megafarmers, that the 'polluter pays' principle has to be applied to everybody, not just to individual citizens," he told the Oireachtas committee.