Havant Thicket reservoir in Hampshire is now expected to be completed in 2034, five years later than planned, after Ofwat paused the project over rising costs. The regulator is consulting for three weeks on a nearly £1bn budget, up from £339m in 2022.
Ofwat said geological problems are part of the cost rise: the reservoir embankment needs redesigning and an extra pipeline must be installed. The project is intended to supply 3.5 million Southern Water and Portsmouth Water customers and reduce Southern’s reliance on the River Test, which it currently draws 80 million litres from daily. Southern’s capital-projects managing director said Ofwat had proposed more funding for the revised scope, including future-proofing for a planned water-transfer and water-recycling project.
It is unclear whether Havant Thicket will go ahead if the revised budget is not approved; a decision is expected by year-end. Southern customers in Hampshire and the Isle of Wight remain under a hosepipe ban. The Environment Agency has forecast a daily water shortage of five billion litres in England by 2050 without improved storage. Southern said last month it intended to charge customers an extra £43 a year next year.
