An agreement in handling water emergencies has been reached in the dispute between NI Water and trade unions.
The agreement means people will not be without water for more than 24 hours.
A row over pensions resulted in an indefinite work-to-rule beginning on Monday.
Yesterday NI Water management said it had agreed procedures with trade unions for "addressing critical issues which present a risk to public health or vulnerable customers".
NI Water management will address trade unions through a specific contact.
Only after the unions agree it is an emergency situation will they deploy engineers to resolve the issue.
The Labour Relations Agency has been called in to try to broker an 11th-hour resolution to the row over pensions. The talks have been aimed at ensuring full cover is in place for faults during the period covering today, tomorrow and Boxing Day.
Hundreds of NI Water workers are taking part in the action.