Havant Thicket Reservoir: Timeline, Pipelines and Access

What is Havant Thicket Reservoir?

Havant Thicket Reservoir is a new reservoir being built just north of Leigh Park, Havant, by Portsmouth Water in partnership with Southern Water. Havant Borough Council's project page describes it as an 8.7 billion litre storage reservoir spanning 160 hectares between Leigh Park, Havant and Rowlands Castle in East Hampshire, designed to safeguard water resources for the South East.

The project's own website says it will be the first large-scale new water storage reservoir in the UK since the 1980s, and the first time two water companies have worked together in this way. It says the reservoir will cost around £340 million to complete and will be paid for over the long term by Southern Water, through its drinking water customer bills, and that Portsmouth Water customers are not paying for it through their bills.

Who approved it?

According to the project's planning and construction page, East Hampshire District Council's Planning Committee resolved to grant planning permission on 9 June 2021, after councillors in Havant Borough gave their support on 3 June 2021. Havant Borough Council says its councillors and East Hampshire's granted permission in 2021 for both the reservoir and a pipeline, that a revised pipeline application was approved by Havant Borough Council in May 2025, and that further applications have since been made to sign off final design details. You can see them on the council's public planning register by searching the keyword Havant Thicket Reservoir.

When will it be finished?

The published dates do not all agree. The planning page still says the reservoir is due to be completed and operational by 2029. The more detailed construction timeline page says the main construction phase began in spring 2025 and that, when completed in the early 2030s, Portsmouth Water will take water from the reservoir during a drought, allowing it to supply Southern Water with 21 million litres of water a day. It also says the shared pipeline approach means the reservoir will be finished later than originally planned, with an updated timescale being confirmed, and that Ofwat must approve the planned costs. No single opening date is confirmed.

Recent milestones on the latest news page include a February 2026 milestone, when a 20 tonne steel Culvert Cut Off Wall was installed in 72 hours, with the embankment to be built over it later in 2026, and a visit by the Environment Secretary reported on 4 September 2026.

What is happening with the pipelines in Bedhampton and Leigh Park?

This is the part that most affects Havant residents. The project's pipelines page says two pipelines will run side by side underground from Bedhampton Springs to the reservoir site, one carrying water to the reservoir and the other helping to supply water during a drought or emergency. A May 2026 news item says the work will take place over the next three years, with the pipelines due to be complete by 2029, along a route of 7km with each pipe 1.7m in diameter, able to carry 40 million litres a day to the reservoir.

Most of the route will be built by micro-tunnelling, which the project says avoids digging up roads and public spaces, with pipes 3 to 10 metres below ground. Two shorter sections will be built by open cut: through Hooks Lane playing fields in Bedhampton and through open space at Staunton Country Park up to the reservoir site. The page lists shaft locations at Meyrick Road and West Street from mid-April 2026, Fraser Road, Hooks Farm Way and Hooks Lane from summer 2026, and Barncroft Way and Stockheath Lane from August 2026. It says you may experience parking restrictions around construction sites, temporary traffic arrangements and some noise, within limits agreed with Havant Borough Council. For where work is happening near you, use the page's links and map rather than relying on this summary.

How will traffic reach the site?

The project's access routes page says planning permission covers two routes. The northern route comes from A3(M) Junction 2 via the B2149, uses a single-track road, and is for most construction vehicles and visitors from further afield. It says this route was chosen partly because it avoids residential areas in Warren Park and Rowlands Castle. The southern route comes off Swanmore Road and is mainly for local communities. Both are designed to end in the site's car park, to avoid a rat run.

What will visitors be able to do?

The community, education and leisure page says the plans include paths for walking, cycling and horse riding extending about 5km around the reservoir and fully accessible, picnic and play areas, and facilities for bird watching. A visitor centre with an information and education area, cafe and toilets is proposed. The project is working with Staunton Country Park, which is next to the site, and Forestry England. These are plans and the reservoir is not open to the public. Staunton Country Park currently houses the project's education programme, according to the same page. For somewhere to visit now, see our Staunton Country Park guide and our Leigh Park guide.

Is water recycling part of the plan?

Not under the approved plan. The timeline page says the approved plan has no element of recycled water. It adds that Portsmouth Water and Southern Water have been exploring adding highly treated recycled water, which it says would secure up to 90 million litres a day extra, under a proposal called the Hampshire Water Transfer and Water Recycling Project that needs further public consultation, regulator approval and planning permission. The pipelines will not carry recycled water unless and until that project is approved and built. Havant Borough Council's page links to Southern Water's Water Recycling Project, so check Southern Water's website for its current position.

How do I get in touch or follow progress?

The project website has a news page, an interactive pipelines map and an e-newsletter sign-up. The pipelines page gives an email address, havantthicket@portsmouthwater.co.uk, a telephone number, 023 9249 9888, and a postal address at Portsmouth Water, PO Box 99, West Street, Havant, PO9 1LG. See also our Bedhampton guide.