The National Poo Museum has submitted a formal objection to Southern Water’s proposed wastewater recycling scheme for the Isle of Wight.
The objection relates to planning application (25/01619/FUL) and raises concerns about public health, environmental protection, legal compliance and the consultation process.
Who raised the concerns
The National Poo Museum says it works with Southern Water to educate the public about what should and should not enter the foul sewer system.
The Museum says Southern Water invited it to take part in the public consultation on the recycling scheme in early 2025, and that this involvement led it to identify serious concerns.
Claims of illegality in trade effluent control
The Museum argues that the scheme relies on sewage that includes trade effluent, some of which it believes is discharged without the legally required permits.”
It points to Section 118 of the Water Industry Act 1991, which makes it an offence to discharge trade effluent without consent.
The Museum says Southern Water confirmed that 15 organisations hold trade effluent permits within the Sandown catchment, with 45 across the Isle of Wight as a whole.
Southern Water says trade effluent is not inherently hazardous and in many cases is cleaner than domestic wastewater.
Southern Water’s explanation
According to the Museum, Southern Water acknowledged that some businesses discharge trade effluent without permits.
The Museum says Southern Water told it that unconsented discharges occur and that the company investigates them, although the Museum questions how consistently this happens in practice.
Southern Water’s technical team said the project instead aims to “design to treat” whatever contaminants enter the system.
Concerns about long-term risk
The Museum argues that this approach embeds decades of regulatory failure into the Island’s future drinking water supply.
It says the scheme would rely on the treatment system never failing over an expected lifespan of around 60 years.
The Museum says this reliance carries unacceptable risk given Southern Water’s past operational performance.
Pollution already identified
The submission highlights existing pollution in Island waterways.
It cites research identifying the River Medina as one of the world’s most polluted rivers for microplastics.
It also notes that the Eastern Yar, from which most Island drinking water is abstracted, contains PFOS and PBDE chemicals (these are persistent trade effluent, including chemical by-products from business activities, linked to long-term health and environmental problems).
Focus on PFAS chemicals
The Museum places particular emphasis on PFAS, often described as “forever chemicals” because they persist in the environment.
It says Southern Water did not provide clear data on PFAS levels in sewage entering Sandown Wastewater Treatment Works. Southern Water says PFAS currently has no formal regulatory discharge limits and therefore does not require traders to install specific treatment for it.
The Museum added,
“There is no internationally recognised safe level for PFAS in blood, but the Cleveland Clinic Journal of Medicine states that ‘Cumulative PFAS levels under 2 ng/mL are not expected to exert negative health effects’.”
The Museum reports that two of its directors paid for blood tests which showed combined PFAS levels of around 12 ng/mL.
They added,
“To be clear, these results don’t demonstrate that drinking water was the cause of elevated PFOS in the blood samples, but they do show concerning PFAS levels and a wider testing programme would help identify where exposure originates.”
Southern Water’s stated position on PFAS
The Museum says Southern Water’s technical lead acknowledged an average PFAS level of 0.024 µg/L in the Eastern Yar.
Southern Water described this level as not “industrially high” and not a cause for concern.
The Drinking Water Inspectorate places this level into Tier 2 for raw water sources, which requires additional treatment and monitoring.
Calls for transparency
The Museum says it repeatedly asked Southern Water for data on PFAS levels in sewage influent, but did not receive written assurances.
It argues that without this data, nobody can confirm whether the scheme would increase public exposure to PFAS.
The Museum describes the sewage stream as a uniquely polluted source of drinking water because it can include landfill leachate as well as trade effluent.
Southern Water says landfill leachate is treated as trade effluent, is subject to strict consent conditions, and contains similar contaminants to domestic wastewater, though in higher concentrations.
Legal risk to the council
The submission warns that approval of the application could expose Isle of Wight Council to future litigation.
The Museum refers to a 2022 High Court judgment which confirmed that planning authorities owe a duty of care to the public.
It argues that approval without conditions to investigate and remedy illegal discharges would constitute an active decision rather than an omission.
Consultation under scrutiny
The Museum also challenges the legitimacy of Southern Water’s public consultation.
It says the consultation materials presented the project as safe and proven by reference to schemes in Namibia, Singapore and the United States.
The Museum argues those comparisons misled the public because overseas schemes rely on strict separation or control of industrial waste, which the Island scheme does not propose.
Claims of misinformation
The submission says Southern Water initially stated in writing that no trade waste entered Sandown Wastewater Treatment Works.
The Museum later concluded those statements did not reflect reality after pursuing further information.
It says many residents would have viewed the project differently if they had known the sewage stream included trade effluent from business activities.
Gunning Principles cited
The Museum argues that the consultation failed the Gunning Principles, which define the legal standards for public consultation.
It says Southern Water’s own brochure shows that decision-makers had already settled on the outcome.
The brochure states,
“We plan to take some of the Island’s wastewater and treat it to a much higher standard so it can be used as a source for drinking water supplies”.
Lack of alternatives presented
The Museum says the consultation did not properly present alternative ways of meeting the Island’s water needs.
It lists options such as enhanced reservoir storage, aquifer storage and changes to abstraction points.
The submission says Southern Water described wastewater recycling as its “most preferred solution” without giving balanced information on cost, energy use, or long-term risk.
What the Museum is asking for
The Museum asks planners not to approve the application without conditions.
It wants a full and transparent investigation into illegal trade effluent discharges and their rectification.
It also calls for a fresh consultation with accurate and balanced information, and for an extension of the public comment period to 2nd February 2026.
Southern Water’s overall position
Southern Water maintains that water recycling offers a safe and established way to secure future water supplies. The company says advanced multi-barrier treatment can remove contaminants and protect public health.
Southern Water also says reducing abstraction from rivers would benefit the environment, particularly during drought conditions. The water company disputes that the scheme poses a risk to public health and says it complies with current regulatory requirements.
A Southern Water spokesman shared this statement,
“The Isle of Wight Water Recycling Project will use advanced treatment techniques to turn treated wastewater into purified recycled water. Doing so will reduce reliance on the mainland, which currently supplies one-third of the Island’s water.
“The purified recycled water will be transferred to the Eastern River Yar, with water taken from the river downstream then being treated again to drinking water standards before it is sent into supply.
“In the reverse osmosis stage of the water recycling treatment process, water is filtered through membranes with holes more than 50,000 times smaller than the width of a human hair. Reverse osmosis is highly effective at removing PFAS and other impurities, which would be released 3km out to sea as reject water.
“We are exploring ways of removing the PFAS from this reject water and, therefore, from the water cycle. Water recycling is widely used around the world to create a drought-proof source of water – which the Island urgently needs.”
Questions to Southern Water
OnTheWight has put the following questions to Southern Water about the issues raised in the National Poo Museum’s submission. Southern Water responded disputing several of the Museum’s claims.
OnTheWight asked,
- 1. Trade effluent and enforcement
How many businesses on the Isle of Wight currently discharge trade effluent into the foul sewer, how many of those hold valid trade effluent consents, and what enforcement action Southern Water takes when unconsented discharges are identified? - 2. PFAS measurements at Sandown
What PFAS concentrations has Southern Water measured in sewage entering Sandown Wastewater Treatment Works, over what period were those measurements taken, and will the company publish the full dataset before the planning application is determined? - 3. Source control and scheme design
Why does the Isle of Wight wastewater recycling proposal not include mandatory industrial source-control measures, when overseas schemes cited by Southern Water rely on strict separation or regulation of industrial effluent?
A spokesperson for Southern Water responded,
“There is no evidence that there are ‘significant’ amounts of trade effluent released without consent. Trade effluent makes up 2-4% of the volume of sewage, most of which is indistinguishable or cleaner than domestic waste. Possible unconsented releases are investigated and resolved by the Trade Effluent team in conjunction with the Network Protection and Enforcement team.
“There are 15 businesses releasing trade effluent under trade effluent consents in the Sandown catchment. There are 45 businesses with consent to release trade effluent across all of the Isle of Wight. Of those 6,700 businesses, many will be office-based businesses that only produce domestic waste. Even of the very small proportion that produce wastewater from a business activity, only a fraction of those will release it into the foul sewer.
“It is the responsibility of traders to apply to release trade effluent legally. Southern Water regularly engages with businesses to ensure they are not releasing trade effluent without a permit and will investigate any information received regarding potentially illegally releases.
“Southern Water always insists on compliance with the conditions of a trader’s trade effluent consent and actively work with traders to ensure they remain compliant.
“Traders are expected to install and maintain any treatment and monitoring equipment required to ensure they remain compliant with their trade effluent release conditions. Non-compliance may result in enforcement action, which may include prosecution.
“For substances that currently do not have formal regulatory guidance (for example, PFAS and other ‘forever chemicals’) Southern Water does not currently impose limits and therefore does not expect the trader to install treatment.
“Landfill leachate is trade effluent. Landfill leachate is subject to strict trade effluent consent conditions, as is all other trade effluent. Landfills are an accumulation of household waste, and so while more concentrated contain the same contaminants as the domestic wastewater that represents more than 95% of the wastewater in our foul sewage network.”
Southern Water also pointed to the terminology used.
“Please refer to trade effluent, rather than changing the name. We would refer to ‘Industrial chemical waste’ as hazardous waste, which we do not accept through trade effluent or tankered waste.
“Trade effluent, simply by being a by-product of a business process, is not inherently dangerous. In many cases it is less contaminated than domestic waste. clean, transparent, and containing nothing hazardous at all.”
A decision still to come
The planning application now sits with Isle of Wight Council for determination.
The Council must weigh technical assurances from Southern Water against the risks and legal arguments raised by the National Poo Museum.
The outcome will shape how the Island secures its drinking water for decades to come.
Article edit
3pm 6th Jan 2026 – Clarifications and further response from SW added
