June 2026 – Southern Water have now submitted the Planning Application to the Planning Inspectorate and this page has been refreshed with additional detail.
A – We get plenty of rain in winter, Southern Water should be developing solutions which store that free natural water for use in dry summers. Less than 2% of rainfall is collected in the UK.
(For further detail see FAQ8, FAQ4, FAQ12)
B – Significant risk to Langstone Harbour of developing the effluent recycling plant and deep tunnel shafts needed on the contaminated landfill site at Broadmarsh (Site 72). There are alternative safer and more suitable sites for the plant which avoid unacceptable environmental risk to to the harbour.
(For further detail see FAQ6, FAQ8, FAQ14)
C – The significant visual impact of the proposed Water Recycling Plant at Broadmarsh particularly from around Langstone Harbour.
(For further detail see FAQ13, FAQ14)
D – There is significant concern about the environmental impact of the effluent recycling scheme discharge into both the reservoir and our coastal waters.
- Not all of the contaminants are removed by the treatment process before discharge into the reservoir, as a result small quantities of pollutants such as pharmaceuticals and PFAS forever chemicals will be discharged daily into the reservoir. Bioaccumulation of contaminants is a risk, especially for PFAS chemicals that do not breakdown in the environment
- The reject water from the effluent recycling plant discharged into the Solent will be 4 times more concentrated than the existing sewage effluent discharged. It will also include treatment and cleaning chemicals, as well as treatment by products
- Southern Water have not modelled all of the contaminants of concern for the discharge into the reservoir, nor our coastal waters.
- There is a gap in the existing regulations which means the EA cannot set discharge limits for all of the contaminants of concern. For more information on the lack of regulatory control click here.
(For further detail see FAQ5, FAQ13)
E – Greener and cheaper alternatives are not being properly investigated & brought forward.
(For further detail see FAQ8, FAQ10, FAQ12)
F – Not a sustainable or cost effective solution, especially building it more than 40km from where the recycled water is needed at Otterbourne. The treatment & energy costs to transport the water 365 days a year will be huge.
Southern Water have estimated in figures provided to Ofwat that the cost to operate the pipeline transfer daily to Otterbourne will be more than £4 million a year.
Southern Water confirmed in their Gate 3 submission to Ofwat that to operate the Water Recycling Plant and pipelines 365 days per year as planned in a normal (non-drought) year will cost more than £13 million every year for what was selected as a drought resource. This is not best value for the customers who ultimately pay this cost, nor for the environment.
(For further detail see FAQ2, FAQ5 , FAQ13)
G – Energy security is already a significant concern, developing energy intensive solutions makes things worse for energy security and the planet. Going forward there will be competing demands for energy which could impact future growth.
(For further detail see FAQ4, FAQ13)
H – Very expensive solution which is not supported by customers, minimum £1.2 billion, with costs spiralling, making it very hard to believe that it will provide ‘best value’ for customers. For example, you could build 3 new winter storage reservoirs for the same cost, and they would still be providing a recreational and biodiversity benefit in 200 years, the effluent recycling plants will be redundant in 60 years.
(For further detail see FAQ4)
I – Totally inadequate public consultation before effluent recycling options were selected. Once the Fawley desalination option was rejected Southern Water should have reviewed all of the alternatives and undertaken a full statutory consultation. Posters should have been put up in all of the areas to be impacted by effluent recycling plants to ensure local communities were made aware of the proposals & consultation. All Southern Water & Portsmouth Water consumers that will be impacted by this significant change to their water supply should have been consulted.
(For further detail see FAQ9 and link to news items)
J – It risks turning people away from tap water due to the lack of trust in the water companies, creating a new used plastic water bottle mountain, especially as mixed reservoir water will taste different to spring water. Customers are already expressing concerns about increased background exposure to contaminants such as PFAS in their drinking water, with regulatory standards always playing catch up as new information becomes available on emerging contaminants of concern.
(For further detail see FAQ5)
K – Loss of a unique biodiversity opportunity to create a chalk spring fed reservoir. The impacts on reservoir water quality and biodiversity are still unknown. However, it must have an impact on biodiversity as the input of recycled effluent to the reservoir will result in changes to temperature, salinity and geochemistry.
(For further detail see FAQ7, FAQ13)
L – Significant additional risk of pollution from the recycling plant, especially if it is not maintained properly by Southern Water.
- No independent monitoring of the discharge into the reservoir is planned.
- Once pollution has been discharged into the reservoir there will be no way of getting it out.
(For further detail see FAQ7)
M – Breakdown of trust in both Southern Water and Portsmouth Water. Given Southern Water’s poor track record of treatment plant and pumping station failures, prosecutions for pollution incidents and failure to take prompt action to rectify problems, how can we trust Southern Water to operate and maintain this complex advanced treatment process?
N – The illustrations on pages 9 and 17 of Southern Water’s 2024 Consultation Brochure are misleading, failing to show that the recycled water will be supplied to Portsmouth Water’s customers in times of drought and emergency with more routine supply after 2040. This information was also absent from the 2022 public consultation, as a result ‘persons likely to be affected’ were not consulted about this fundamental change to their drinking water supply.
(For further detail see FAQ1)
O – In 2024, Southern Water were losing 100 million litres of water every day to leaks, that is 19% of all the water they abstract from the environment, which customers pay to treat, wasted through leakage in their distribution system. Yet their slow programme for improvements means even by 2050 they will still be leaking about 10% of all the water they treat, including the new water manufactured at huge cost from their planned new effluent recycling schemes. Without a more ambitious mains replacement programme they will never get leakage under control.
An industry leakage specialist tells us that if Southern Water prioritised and funded leakage reduction they could strive to achieve a 50% reduction by 2040 and a 70% reduction by 2050, rather than the 53% leakage reduction target they have set themselves by 2050.
(For further detail see ‘Alternative Options’)
[Last updated, 25-11-2024]