The Right 2 Water campaign said it will hold the country's largest ever protest on the weekend before the General Election.
The group is preparing for 30 protests around the country this Saturday, calling for the scrapping of Irish Water and water charges.
Right 2 Water spokesman Brendan Ogle says households are being asked to pay 78% of the bill for water, despite only using 10%.
"90% of the water that we use is used by corporations and agriculture - just 10% is used by households," he said.
"However, those households are being asked to take onboard 78% of the costs."
He added: "The last two Irish governments cut funding for our water and sewage services from €839m in 2008 to €289m in 2013 – a cut of 65% in five short years.
"Is it any wonder we had boil water notices in places like Roscommon and Galway?
"But they now have the cheek to come to us and say the system is underinvested and we need water charges."