Northern Ireland Water has appealed to customers to use less water or expect a hosepipe ban this summer.
Household consumption has risen during lockdown coinciding with hot weather, which has led to water networks struggling to keep up with demand.
The company said increased home usage has not been offset by a reduction in business usage because high level consumers such as agri-food and production have remained operational throughout lockdown.
As with the rest of the UK, reservoir levels are depleted following the dry spring.
Chief executive Sara Venning said a period of sustained “reasonably wet” weather was needed to make a significant change to the reservoir levels.
Venning said: “There are a number of steps NI Water can take to alleviate the stress on reservoirs including a hosepipe ban. However, the key to conserving water is public action now. How we all use our water now will have a massive impact on our water levels during the summer months and whether a hosepipe ban will be required.”
Sector-wide requests for householders not to use sprinklers or garden watering systems and be mindful of their water consumption have been made, backed by Water UK.
Droughts have been forecast for many parts of the country despite the wet winter river flow and groundwater levels remain below normal for the time of year.