Unprecedented demand for water will likely lead to a hosepipe ban in the coming weeks, Irish Water has said - while new evidence suggests current global temperatures could lead to a doubling in 'water stress' by 2050. According to the United Nations, water stress is when the demand for water exceeds the available amount during a certain period, or when poor quality restricts its use.
Water stress causes deterioration of fresh water resources in terms of quantity, such as dry rivers, the UN's Environment Programme says.
A new study by Earth's Future has found that by 2050, the global population under water stress is expected to increase by 50% under a low population growth and emissions scenario, but could double under a high population growth and emission scenario, compared to the year 2010.
The authors of the study, which has been peer-reviewed, said: "As changes in water availability have a smaller effect when water is not yet scarce, changes in water stress globally are dominated by local water consumption – managing local demand is thus necessary in order to avoid future stress.
"Moreover, an increased number of people will be living in areas dependent on upstream originating water in 2050. International water treaties and management will therefore have an increasingly crucial role in these hot spot regions to ensure fair management of transboundary water resources."
If the high population growth and emissions scenario was to play out, it would mean an extra 380 million people facing water stress by 2050 compared to in 2010.
The low population growth and emissions scenario - such as under the Paris Climate Agreement, where the increase in global temperatures would be limited to a two-degree increase - would still lead to a 50% increase, Earth's Future found.
Irish Water has warned of a hosepipe ban with water supplies diminishing to drought-like conditions during the recent dry spell.
The body said there has been “unprecedented demand” over recent weeks as it appealed to the public to only use water for necessary activities.
Yvonne Harris, the utility’s head of customer operations, told RTÉ's Morning Ireland that 16 water supplies are already classified as at drought level, while a further 38 are in the drought-pending category.
“We feel it is highly likely we will be required to implement a water conservation order,” she said, adding that on hot days “demand is soaring beyond any previous levels.”
“Last Saturday when it was a very hot and sunny day in Dublin, we experienced an additional demand of 30 million litres of water.
“That is the equivalent of an additional 200,000 people (using water) in Dublin. And we have found that our data is showing similar trends throughout the country," Ms Harris said.
Supplies from rivers, lakes and springs are drying up, according to Ms Harris.
Technical teams at Irish Water are currently monitoring supply levels and a conservation order is expected to be announced once they have dipped to levels stated under the utility’s criteria for restrictions.
Ms Harris said she could not predict when it would be announced or how long it would last, as it would be weather dependent. She appealed to the public not to use water for “unnecessary purposes”.