Previously up to 12 million litres of water a day were pumped from Southern Water’s Testwood Water Treatment Works, in Southampton, to the Isle of Wight through the Cross Solent Main.

This main is made up of twin four-kilometre pipes which lie under the seabed beneath the Solent, running between Lepe, in Hampshire, and Gurnard, on the Isle of Wight.

The old pipes were put in more than 25 years ago and were ageing and needed replacing.

So, Southern Water decided to invest in two new, bigger pipes to help secure and increase the water supply to the Island.

The £15 million Cross Solent Main replacement scheme began in 2003 and reached the final stage in April 2008 – laying the new pipes under the seabed of the Solent.

The Water Source

The water which is pumped to the Island through the pipes comes from Testwood Water Supply Works, in Southampton.

It is Southern Water’s largest works in Hampshire and licensed to abstract up to 136 million litres of water a day from the River Test.

The works supplies up to 200,000 customers in Totton, Waterside and Southampton, as well as parts of the Isle of Wight, via the pipes running under the Solent.

The water is treated and disinfected before being pumped underground to Lepe in the New Forest, across the Solent, round the Island and finally to customers’ taps.

Find out about water supplies on the Island.