Householders in Northern Ireland could face annual water bills of up to £50, on top of their yearly rates bills, in order to upgrade the North's water service to European standards.
Northern Ireland must find £2.5 billion to upgrade the supply system over the next 15-20 years.
A Northern Ireland Office consultation paper was published yesterday on possible ways of finding the finance.
The water service in the North has warned that higher charges are inevitable to meet the European environmental standards.