Q&A
- We already have agreements to share up to 30 million litres of water a day with Southern Water (in West Sussex and Hampshire).
- We can share a further nine million litres a day from 2024 from other sources (Hampshire)
- We can provide an extra transfer from a mix of sources when the reservoir is built, up to 21 million litres a day (to Hampshire)
- The total would be up to 60 million litres of water per day provided to Southern Water.
- A wetland habitat to support threatened bird species and provide areas for endangered bat species to find food
- A visitor centre with a café and facilities for communities and schools
- A network of trails and paths for walking, cycling and horse riding, linking to others in the wider area
- New woodland, hedgerows and wildflower planting
- A landscaped parking area for vehicles and bicycles.
- Ongoing creation of new woodlands and habitats for wildlife migration
- Prepare planning applications for the detailed design of the reservoir operational and visitor facilities, access and recreational routes and the pipeline route
- Build the access roads
- Start work to prepare the site
- Divert paths
- Community engagement.
- Dig out the clay and move it within the site to shape the reservoir bowl
- Build the embankment
- Lay the pipeline which will transfer the water from the springs to the reservoir
- Community engagement.
- Create a new network of paths
- Pump water from the springs to fill the reservoir (during winter)
- Build the visitor centre and other facilities
- Open to the public.
- Sending out a letter from Portsmouth Water CEO Bob Taylor in October 2019 to 27,000 local homes and businesses to tell them about the reservoir and direct people to where they can find out more
- Carrying out customer research to gauge people’s attitudes on the reservoir, with the vast majority of those surveyed supportive of the project
- Setting up a dedicated Facebook page and these web pages for Havant Thicket Reservoir, making it easier for people to learn more and get in touch to ask questions
- Holding a series of public exhibition events in November 2019, with face to face discussions with residents
- Liaising closely with a wide range of community representatives to get their input into our proposals – e.g. we’ve been talking to local MPs, councillors, council officers, environmental and community groups and organisations like Forestry England and Staunton Country Park
- Holding a public consultation on the reservoir project proposals from 11 May to 8 June 2020.
What is the plan for a new reservoir?
We are planning to invest £340 million to build a new reservoir in Havant, Hampshire. It is being built in collaboration with Southern Water and will help secure more reliable and resilient water resources for our area and the wider South East.
Why is it needed?
The South East, as a whole, is under ‘serious water stress’ and water companies are being asked to take less water from some of their sources – such as the chalk rivers in Hampshire – to keep them healthy and protect wildlife.
At the same time, water companies need to find more water to cater for the effects of climate change and a growing population.
This major change is going to particularly affect Southern Water, which needs to find new water resources for the customers it supplies drinking water to in Hampshire, to replace water taken currently from the River Test and the Itchen.
In Portsmouth Water's area, there are underground springs which provide plentiful, clean water. In winter, much of this water is surplus to requirements and flows out to sea, so we could make better use of some of it by capturing it and storing it in the reservoir until it’s needed.
This will allow us to share more water with Southern Water’s customers in Hampshire from our network and increase the resilience of water supplies in the South East.
Overall, building the reservoir would make the whole South East much more resilient to droughts, which are likely to happen more often in the future due to climate change.
Why has the reservoir not gone ahead before?
We first received planning permission for the reservoir back in 1964 and we carried out a lot of work towards a new planning application in 2008.
However, at the time there wasn’t enough demand for the water, either from our customers or across the South East.
Since then, Southern Water has agreed to reduce the amount of water it takes from the Rivers Test and Itchen in Hampshire, to protect the environment, so they need to find new sources.
As a result, we’re now working in partnership with Southern Water to go ahead with the reservoir to 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.
What would the reservoir offer to Portsmouth Water customers?
As well as being supplied with water from the reservoir, our customers would have the benefit of a new community leisure facility on their doorstep. There would also be a host of environmental benefits locally.
The reservoir site would create a new, healthy and safe place for people to visit – with footpaths for walking, as well as routes for cycling and horse riding, facilities for bird watching, picnic and play areas and car parking.
There would be a visitor centre with a café, toilets and space for community and education activities.
Our proposals for the site so far have been developed over many years with local communities, young people and organisations such as Staunton Country Park and Forestry England.
What would the reservoir offer to Southern Water’s customers?
Building the reservoir would allow us to share water supplies with households in Hampshire (outside of our supply area) who receive their drinking water from Southern Water and where there is a severe shortage.
This means Southern Water’s customers would have reliable water supplies and less water would need to be taken from the River Test and River Itchen, which would be better for the environment.
Our customers in Hampshire who we supply water to are also customers of Southern Water for their wastewater services, so everyone in the area would benefit from the community and leisure facilities at the reservoir.
What would the reservoir look like?
The reservoir would be about one mile (1.6 km) long from east to west and 0.5 miles (0.8 km) wide from north to south. It would be up to 18 metres deep and have embankments on three sides. The below image shows what the reservoir could loo like when completed and open to the public.
What activities would be on the site?
We’re planning to build a visitor centre on the site with a café, toilets and space for education and community activities.
There would also be footpaths for walking, cycling and horse riding, facilities for bird watching, such as bird hides, and picnic and play areas. Furthermore, there would be car parking and cycle racks.
We’re working in partnership with neighbouring Staunton Country Park and Forestry England, organisations we already work very closely with, to make sure the facilities and activities are a good fit with theirs.
What about the environment and wildlife on the site?
Our approach to designing the reservoir has the environment and the community at its heart. Further details are set out below.
Our masterplan covers all the environmental and community factors we are taking into account. This means we’ve considered the environment as we’ve designed every part of the reservoir, the access roads and pipeline, and we’ll continue to do so.
We’re also working closely with Forestry England, who own and look after the neighbouring Havant Thicket woodland, and Staunton Country Park (which is owned and run by Hampshire County Council) to see how we can manage the sites together in the future.
This approach, along with lots of feedback from local communities and environmental organisations, has helped us choose the facilities we’re proposing, namely:
The reservoir project will improve existing woodland and create a valuable new wetland, woodland and parkland. A grant scheme will also support wildlife across Hampshire and West Sussex.
Creating the reservoir will help protect the River Test and River Itchen in Hampshire. By using the reservoir to supply our own customers, we can share supplies from our other water sources with Southern Water. This means they will be able to reduce the amount of water that they take from these rare and sensitive chalk streams, which are home to many species.
We would need to remove 12.5 hectares of ancient woodland to build the reservoir and we have reduced this as much as possible by changing the design. We’re committed to replanting and improving around 200 hectares of woodland and pasture both on and around the site and further afield to leave an overall positive gain for the environment and communities.
Where would the road access to the reservoir be?
We need to create new public roads for vehicles to get in and out of the site, both while the reservoir is being built and when it opens to the public.
We've been granted planning permission for two access routes to the reservoir – one from the north and one from the south, as set out on the below map.
We want to create access roads from the north and the south to help minimise the overall impact of traffic and almost halve the amount of ancient woodland we will need to remove along the northern route.
We will use the northern route for most of the reservoir construction vehicles and people travelling from further afield to the site, with the southern route mainly used by local communities. We’ve designed it so both roads end in the site’s car park and the northern route is single track, to avoid the routes being used as a ‘rat run’, something people told us they were particularly concerned about.
You can read more in the ‘You said, we did’ consultation report we published, summarising what people told us during our Spring 2020 consultation and how we’re responding to the points raised.
The northern access route
A number of routes from the north were considered during the public consultation in 2008 and the preferred one came from the A3(M) Junction 2 (J2) via the B2149. At the time this was supported by a majority of people because it was close to the A3(M) and avoided residential areas in Warren Park and Rowlands Castle. This helped us develop our updated northern access route proposal (see map above) which formed part of the planning applications we submitted in late 2020 and which was then granted planning permission in Autumn 2021. From the B2149, 200 metres of new track will be needed through woodland, then the road will follow the route of an existing Forestry England track in Havant Thicket woodland to reach the reservoir.
The southern access route
As we studied the reservoir site in more detail, through developing our planning applications, we were able to make changes to the design of the embankment. This created more space on the south west side of the site, meaning there is enough room there now to build the embankment, an access road and a separate path for walkers, cyclists and others.
So we developed a plan to create an access route from the south, in addition to the northern one. This access point will come off Swanmore Road and follow a new road on the site along the side of the reservoir and up to the car park and visitor centre.
How much would the reservoir cost and who will pay for it?
It would cost about £120 million to plan, build and fill the reservoir with water.
The scheme will be funded by payments from Southern Water to purchase the water it needs to supply its customers. Southern Water has considered a number of options to supply water to its customers and the reservoir is considered to be good value.
Only Southern Water customers who receive drinking water supplies from them will have the cost of the reservoir reflected in their bills. So, this does not include our customers who receive drinking water from us and wastewater services from Southern Water.
Portsmouth Water already has among the lowest water bills in the country (£100 on average).
When would it happen?
Timeline
The reservoir will take nine years in total to plan, design and build and is scheduled to be complete, full of water and open to the public by 2029.
A huge amount of work has already been completed to share information, draw up detailed plans, carry out environmental mitigation work and prepare the site for building work
This diagram below sets out our timescales, with construction taking place in phases.
Construction
The task of building the reservoir is a large one which will take a number of years. It will involve the combined expertise of a team of engineers, planners and a large workforce to complete this major project. As the site is in a natural valley and made up of clay, we expect to be able to dig this to shape the reservoir without having to bring in extra material or remove it. During the construction we would liaise regularly with communities to keep disruption to a minimum and create opportunities for local employment and education.
Projected timeline
2021-2022:
2023 – 2026:
2027 – 2029:
How are you involving residents and communities and other organisations?
Since 2019, we’ve carried out a range of activities to raise awareness about the reservoir and encourage people to find out more and tell us their views. This has included:
How can I find out more?
There’s lots more information on this website, where you can also give us your questions and comments using the 'Ask us a question' tool on each page.
You can also get in touch with us via email, phone or post. See our Get in touch page for more.