Two of the largest trade unions in the country are calling on the government to scrap water charges.

Unite and Mandate say the charges, which came into effect yesterday, are unconstitutional and a breach of human rights.

They are organising a national demonstration against water charges to be held in Dublin city centre on Saturday October 11th.

The 'Right2Water' campaign is supported by a range of trade unions, political parties and community groups.

The group says that water is a human right and wants to see the charges reversed.

Spokesperson for 'Right2Water' is Brendan Ogle. He says the charges are a step too far by government.

Meanwhile a family with 13 children in Carrickmacross in Co Monaghan have discovered that based on current usage, their water bill is set to be almost €4,000 a year.

Paul and Edel Maher say their household uses over one million litres of water per year.

But despite the water allowance of 30,000 litres per household, plus the 21,000 litre allowance for each of their 13 children, the family still faces a bill of €3,930 a year.

Nr Maher told the Pat Kenny Show here on Newstalk he is shocked by the figures.