Water supplies are usually low at this time of the year, having been depleted through the spring and summer months when seasonal rainfall tends to be lower than over the autumn and winter.
Last weekend, when the most recent measurements were taken, reservoirs were 59 per cent full at a time when the ten-year average would expect to see them at 68 per cent.
‘While the current position is below the average, it is not out of the ordinary and currently presents no cause for concern and [we are] not near the point when we would consider the use of the desalination plant at this time of year,’ Jersey Water’s chief executive Helier Smith said.
The desalination plant at La Rosière, on the coast between La Moye and Corbière, has recently undergone a £6 million upgrade, increasing its output capacity from six million litres a day to 10.8 million, about half of the Island’s daily demand for water. When operational, it removes the salt from sea water, which is then pumped into Val de la Mare reservoir for dilution with fresh water to top up the company’s resources during times of extreme shortages. It has not been used since 2013.
Below-average rainfall of just 35.6 mm was recorded in September, following the pattern of the summer months and Mr Smith says the dry conditions look set to continue into the winter.
‘Our long-range forecast suggests that October to December may be drier than average,’ he said. ‘We obviously keep water resources under daily review.
‘The lowest we have seen over the last ten years at this time of year was in 2011, when we had 49 per cent water in store.’
In spite of the hot summer, Mr Smith says demand for water from June to September was 1.4 per cent down on 2017.
‘This is as a result of two main factors,’ he said.
‘Leakage is down by 20 per cent on the previous year to date due to our leakage management initiatives. And now that our customers are metered, they are in control of their water bills and they are less inclined to waste water. For example, simply turning off the tap when you brush your teeth can save six litres of water a minute.’