Neighbours Havant Borough Council and East Hampshire District Council have given planning permission for the 8.7bn-litre storage reservoir to be built between Leigh Park in Havant and Rowlands Castle in East Hampshire.
Also approved was a pipeline to extract water from the reservoir and to fill it with surplus water from the Bedhampton Springs in winter.
The £140m Havant Thicket Reservoir is a collaboration between Portsmouth Water and Southern Water to safeguard water resources in the region. It will also create a wetland with bird watching facilities.
During the meetings, held at both local authorities, concerns were heard from The Woodland Trust, Havant Climate Alliance, Friends of the Earth and residents about the removal of ancient woodland. Councillors weighed up the impact of the loss of these trees against the benefits that would protect other habitats and local chalk streams, the rivers Itchen and Test.
Government regulators Natural England and the Environment Agency told the councils that they were satisfied by the water companies’ proposed mitigation and compensation strategy for the loss of irreplaceable habitats.
Councillor Clare Satchwell, cabinet lead for planning at Havant Borough Council, said: “This major project has been talked about in the borough since the 1960s and after a comprehensive report and presentation at Havant's Planning Committee on 3rd June, the committee considered the applications for Havant Thicket Reservoir and gave permission, subject to completion of a section 106 legal agreement.”
East Hampshire District Council planning lead, Councillor Angela Glass, added: “The reservoir will secure more reliable water supplies for the region as a whole. It will also help cater for a growth in the population and housing and more droughts as a result of climate change.”
Portsmouth Water chief executive Bob Taylor said: “As well as securing much-needed future water supplies, Havant Thicket Reservoir will help safeguard the River Itchen and River Test, two of Hampshire’s rare and world-famous chalk streams, by enabling less water to be taken from them. It will also create a new green leisure hub for people and wildlife.
“I would like to thank the councils for their support on this vitally important scheme and we’re also very grateful to local people and community representatives for their strong backing and valuable feedback over a number of years, which have helped shape the plans and our approach in many areas.”
Final legal commitments for the reservoir scheme will now be agreed with both authorities and full permission could be granted by early summer. Work would then begin with further environmental work to support wildlife mitigation. Havant Thicket Reservoir could then open to the public in 2029.
Main construction work is on course to start next spring 2022. Balfour Beatty, Hochtief and a Mackley Jones joint venture are competing to build the reservoir, having been shortlisted last month. Clancy Docwra, Farrans Construction, Roadbridge UK and Ward & Burke are shortlisted for the pipeline.