Engineers will comb the network, reducing pressure in certain localities as they go, trying to locate and fix leaks.
Reportedly, some local authorities are losing as much as 40pc of their supply to leaks.
Irish Water’s goal is to improve leakage rates by 2pc by the start of next year.
Engineers will also be finding and fixing leaks as they attempt to improve an old system with “thousands of leaks all over the place” a spokesperson for the company said.