Water levels at key reservoirs in Northern Ireland have dropped by almost 1.8 metres following a long spell of dry weather.
Water supplies at Fofanny Dam and Silent Valley in Co Down are below the levels which would be normally seen at this time of year.
It comes after the province recorded its driest April since 1980.
Last month only 28.66mm of rain fell, which is well below the monthly average.
Pictures taken at the Fofanny reservoir yesterday show water levels have fallen significantly over recent weeks.
Located in the heart of the Mourne Mountains, Fofanny treats up to 52m litres of water a day from three nearby sources - Fofanny Dam, Spelga Dam and Lough Island Reavy - to serve more than 100,000 customers in the area.
A number of locals expressed concern over the lack of rainfall, including farmers who fear it will affect their crops.
"It is unusually low at this time of year, parts of the reservoir is exposed and you can clearly see where the water level used to be," said one resident.
"I'm not too concerned, as hopefully the expected rainfall will help bring the levels up again."
A spokeswoman for NI Water said that it was "closely monitoring" the situation.
"We continually check water levels in our key reservoirs across Northern Ireland," she said.
"Levels in a small number of reservoirs are slightly lower than we would normally see at this time of the year due to the drier winter period in 2016, followed by a very dry April. However, we expect the predicted rainfall over the coming weeks will help levels in reservoirs to rise again.
"This is a timely reminder that we can all play a role in conserving water."
Thousands of litres can be saved domestically every year by ensuring the dishwasher or washing machine is full before use, or by taking a shower rather than a bath.
Local DUP councillor Glyn Hanna said: "I spoke to one of the engineers who works on it and they said that a spell of a few weeks of rain would ease the pressure.
"It's not a massive concern, but people are talking about it."