JERSEY’s desalination plant saw its “longest run in recent history” last year – producing enough water to fill Grands Vaux Reservoir more than twice over.
Jersey Water’s head of water resilience, Mark Bowden, revealed the figure while providing an update on storage levels.
The Island’s reservoirs are currently at 94% capacity – a notable improvement on the figure of 57% documented in October, when consumers were asked to make “small but vital” changes to their daily routines to save water.
“It’s a good position to be in,” Mr Bowden said. “Our rule of thumb is that we like to be full by the end of December, but December – in particular the second half of December – we had a particularly dry spell, so we hadn’t filled up.
“The next date we look towards is 1 April.
“If we’re full on 1 April, you have a fighting chance of making it through the summer without having to put any restrictions in place – but it all depends on how dry the spring is.”
Mr Bowden noted that part of the reason capacity levels hadn’t reached 100% was due to work taking place at Val de la Mare Reservoir, which has been “deliberately held down” to enable access.
Last summer, the utility company urged customers to be cautious and to not waste water, with reminders issued in winter amid concerns over reservoir levels.
“We did a bit of a customer survey, specifically asking whether customers have changed their habits,” Mr Bowden said.
“And 40% of the customers who responded said, yeah, I did change my habits as a result of the campaign that you put out.
“While that’s not everybody, I think it’s a pretty good result overall and we saw the benefits of that.”
Mr Bowden also pointed out that the more water Islanders could save, the less need there would be to use the desalination plant, which he revealed produced over 500 million litres in 2025 – more than twice the capacity of Grands Vaux Reservoir.
“We originally started it up in July and it ran through till October, and then we had a bit of a wet spell,” he continued.
“We thought, things are on the turn, it’s going to refill, we’re in the autumn – and then it went dry again.
“We started to lose our storage levels, so we started it up again in mid-October and it ran then through until early December.”
He described last year’s use of the facility as its “longest run in recent history”.
“Certainly since we modified the plant in 2015,” he added.
