Why do we need desalination in Cornwall?

South West Water provides water for 2.2 million people living in Cornwall, Devon and parts of Somerset and Dorset as well as in the Bournemouth area and the Isles of Scilly.

Climate change, an increasing population and the significant influx of visitors to the region each year have made water resources more in demand than ever, especially in Cornwall.

We will need an additional 4 billion litres of water by 2050 to meet demand and the Met Office is predicting that by 2070, summers will actually get drier overall – with more heatwaves and droughts.

To avoid hosepipe bans and the need for emergency drought measures in the future, we are:

• Fixing more leaks
• Encouraging behavioural changes
• Running water efficiency campaigns
• Converting former clay pits into reservoirs, e.g. Blackpool Pit and Hawk’s Tor

However, these resources alone are not enough to provide us with the resilience we need. That is why we are developing plans for desalination, which aren’t reliant on rainfall. The steps we are taking will boost Cornwall’s water resources to approximately 45% by 2025.

Why now?

Our regulators, like the Environment Agency, are encouraging water companies to develop new water supplies that are not reliant on rainfall and they recognise desalination as an important step in ensuring resilient supplies in a changing climate.

Advances in NetZero technology means we can now offset some of the energy requirements of desalination and approach these schemes in a much more sustainable way than before. Desalination technology itself has also progressed, meaning that processes are more efficient than ever before.

This, combined with the need to do more to secure the region’s water supplies for the future, means now is the right time to progress our plans.

Benefits?

Building a desalination plant greatly increases Cornwall's resilience to climate change. It would:

• Provide a climate independent source of water
• Be part of a range of new sources, including, reservoirs and naturalised clay pits
• Be a ‘turn on/turn off’ resource that we will only use when climate puts pressure on our water resources
• Reduce the need for drought permits and water abstractions from local streams and rivers, boosting biodiversity and keeping them healthy even in times of drought
• Reduce hosepipe bans

Project update: Screening submission update

As you will be aware, we recently announced our approach to phase the delivery of the Par desalination project.

As part of this phased approach and to satisfy planning requirements, South West Water were required to submit a screening opinion request to Cornwall Council to determine if our proposed application for Phase one required an Environmental Impact Assessment (EIA). This screening opinion was submitted to Cornwall Council on 29 April 2024.

We can now confirm that Cornwall Council have informed us that the proposed development (phase one application) is not considered to be an EIA development  and therefore an Environmental Impact Assessment is not required.

South West Water has fully complied with the EIA process provided the relevant information that was required to Cornwall Council who then undertook their own independent process to determine the outcome of the screening request.

You can find a link to the screening request opinion here and using reference number PA24/03433.  

South West Water announces phased approach to deliver desalination in Cornwall

South West Water has announced it will deliver its proposed desalination project for Cornwall in two phases, as it continues to invest in long-term water resilience across the region.

The company is investing £125 million to increase water resources in Cornwall and Devon by 2025 to break the cycle of drought. This includes plans to deliver a climate-independent source of water to customers in Cornwall through a new desalination plant in Par which is consistent with other proposals for development for the area.

Due to the complexities of the project, the sensitivities around marine impacts and the pressing need to secure resilient water supplies, South West Water will focus on delivering a smaller plant in 2024, using existing pipework to avoid any negative impact to the marine environment.

This plant will be capable of producing between 2.5 and 5 million litres of clean drinking water each day when needed, and will allow the company more time to develop its application for a larger desalination plant, working closely with experts to understand the marine and natural environment in St Austell Bay.

The proposed larger desalination plant will replace the small one and reuse as much of it as possible to produce up to 20 million litres of drinking water daily, as previously announced by the company.

To find out more see the Phase 1 section below.

Our proposals

We are proposing a desalination plant in Par. Par is an ideal location as it’s near to Restormel Water Treatment Works, the sea and has a dock and industrial area more suited to this kind of development.

Protecting and enhancing the environment and minimising the impact of this project on the local area is our key priority. Over the last few months, we’ve been working hard behind the scenes to gather more environmental data, which will help us, and our regulators clearly understand the potential impacts of this project and how they can be minimised.

Due to the complexities of this project, the sensitivities around marine impacts and the pressing need to secure resilient water supplies, we have decided to phase the delivery of this project.

The next steps and timeline

We are now liaising with Cornwall Council, which in consultation with Natural England and the Marine Management Organisation, will tell us what environmental information will be required to support the Phase 1 planning application. We will utilise the work we have done to date and carry out further environmental surveys and assessments.  

We plan to submit a planning application for Phase 1 in the summer. Subject to gaining the necessary approvals, consents and planning permission, we will start construction later this year.

A planning application is also required for Phase 2 and we will keep you updated on these proposals and again, consult the local community before submitting a planning application later this year.

View the timeline for Phase 1 of the Par desalintation project,

All timescales are subject to consultation with our Regulators.

Engagement and consultation

In December 2023, we held stakeholder briefing sessions and public information events so that local people could find out more about our proposals.

We will be holding further briefings and public information events and will share more details about Phase 1 in early summer.

We will also consult on details of Phase 2 later in the year.