Connecting every home in Jersey to mains water would cost almost £40m, Jersey Water (JW) has told the government.

Answering a question from Deputy Steve Ahier, Treasury Minister Deputy Elaine Millar revealed nearly 3,000 homes were without a mains supply.

As government shareholder representative for JW, she said it would need to install 90km [56 miles] of new pipes to connect the remaining properties.

The government was advised at the start of April that private borehole water supplies in the island were contaminated synthetic chemicals.

Millar said JW estimated the total cost of bringing mains water to all remaining properties that were located more than 50m (165ft) from an existing main "would exceed" £36m.

She said: "Connection of properties to the water main would be subject to an additional connection charge for customers and the cost of modifying internal pipework.

"The timeline to complete this work would be dependent on the funds available each year and other competing operational factors."

Millar added that, since 2020, JW had spent £777,000 extending the mains network by almost 3km (1.9 miles) to 105 properties.

'Multiple factors'

Miller said JW was "committed" to reaching more homes with mains water.

"Jersey Water reviews and prioritises its capital investment for extending the mains network on an annual basis, taking multiple factors into account including cost, water quality, and customer demand," she said.

She added that JW did not hold information on the number of private boreholes and wells, but it estimated that 2,800 properties were without mains water – about 5% of domestic properties.

She said: "Jersey Water's policy is to undertake extensions when funding is available, without increasing risk in other operational areas, and also ensuring that the connections deliver the best economic outcomes for the company, its customers and the island.

"The number of new water mains that Jersey Water installs varies from year to year, depending on competing operational and financial factors."

She said the company had a "detailed mains extension programme" ready to deliver when "funds permit".

She added the company had to balance upgrading the mains water infrastructure with reducing leakage, installing chemical treatment and the island's future water resource challenges.