Guernsey Press

Island’s water reserves stronger than Jersey’s

GUERNSEY’S reserves can provide water for up to 11 months, putting the island in a stronger position than Jersey.

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St Saviour’s Reservoir, one of 15 operational reservoirs in the island, is currently 60% full. The total water reserves in Guernsey are at an ‘acceptable’ seasonal level with current capacity at 78.7% full, whereas Jersey Water recently announced it was using millions more litres of water from its reservoirs each day than it was able to replace. (Picture by Peter Frankland, 25900977)

Jersey’s water reserves, at full capacity, would last its population only four months – 36.4% of the timescale Guernsey reserves could supply the island.

Guernsey’s water reserves are currently at an ‘acceptable’ seasonal level with current capacity at 78.7% full, equating to approximately 3,452m. litres.

Jersey Water recently announced it was using millions more litres of water from its reservoirs each day than it was able to replace and that the desalination plant was likely to be brought into action.

Efforts to encourage businesses and the public to become more water efficient would not do enough to address an eight million litre deficit expected to hit the sister isle by 2045.

Guernsey Water’s general manager Steve Langlois Langlois said: ‘We are very fortunate to have a good level of water storage capacity on island, allowing us to take full advantage of collecting water during the wetter months of the year in order to see us through drier periods. In line with our Water Resources & Drought Management Plan released earlier this year, we monitor water resources closely. This allows us to act appropriately in line with our reserves, carrying out internal changes to reduce impact on customers and providing us with a guide to when any wider measures may be required.’

It is normal practice for raw water to be transferred between Guernsey Water’s 15 operational reservoirs via a network to ensure the island’s three water treatment works are kept supplied.

For this reason, a lower level within any reservoir does not necessarily reflect overall water reserves.

For example, St Saviour’s Reservoir is currently approximately 60% full, which is less than the current capacity of the island’s reserves.

The majority of water reservoirs on the island were formerly quarries, with the largest water storage reservoir being Longue Hougue, previously a quarry, now capable of holding approximately 1,159m. litres.

Mr Langlois continued: ‘Our total storage capacity provides around 11 months of water supply, based on average demand in dry weather; on Jersey this is around four months. This means that Jersey Water is inevitably required to bring in wider measures to supplement supplies at an earlier stage, as announced recently with the upcoming use of their desalination plant.

‘We would like to remind islanders that despite the current water storage levels, using water wisely in businesses and homes is still just as important for preserving the island’s supplies and protecting our environment.’