Concerns have been raised over the protection of vital water supplies following a controversial planning decision.
Campaigners warn that a ruling by the Planning Inspectorate allowing major engineering works to proceed at Thames Farm, near Henley, undermines national safeguards for drinking water aquifers and sets a worrying precedent for future development.
The approved works involve injecting grout into unstable chalk ground above a Principal Aquifer located within Source Protection Zone 1 (SPZ1), the highest level of protection for groundwater used in public water supply.
This aquifer currently provides drinking water to around 50,000 residents across Henley, Shiplake, and Harpsden.
The plans were opposed by South Oxfordshire District Council and challenged throughout the planning process by local councils, independent experts and residents due to fears of groundwater contamination, long-term damage to water resources, changes to groundwater flows, and increased flood risk.
Despite these objections, the Planning Inspectorate ruled that risks could be mitigated through planning conditions.
Laura Reineke, chief executive of Friends of the Thames and Henley Mermaid, said: “If protections attached to the highest category of drinking water source can simply be overridden when development pressure demands it, then those protections become meaningless.
“The precautionary principle exists for exactly these situations.
“Once an aquifer is contaminated or damaged, there is no reset button.
“The question should never be whether we can manage the consequences afterwards, but whether the risk should be taken in the first place.”
Kate Oldridge, executive director of Greener Henley, said: “Water is not an optional extra.
“Every home, school, hospital, business and farm depends on it.
“Once an aquifer is damaged, you cannot simply build another one.”
Campaigners also point to other nearby developments, such as the proposed Pony Field scheme, which they say will further strain the Thames region’s already limited water and wastewater resources.
They argue these developments are considered in isolation, without examining the combined impact on water supplies, sewage infrastructure, river health and flood resilience.
Pressure is also mounting on the Wargrave Sewage Treatment Works.
Citizen scientist Dave Walace, co-founder of HoT Water, said: “Based on extensive testing, we have concluded that Wargrave STW is a major source of bacterial pollution in the Thames between Wargrave and Henley. We have tested above the outflow, the outflow itself, and at various points in the river below, and have obtained a consistent picture of low E. coli readings above the outflow and extremely high readings at, and below it.”
Peter Boros, chair of the Thames Farm Action Group, said: “This has been a six-year battle to protect a drinking water source serving 50,000 people.”
He said: “Local residents, councils and independent experts repeatedly raised concerns, yet those concerns have ultimately been set aside.”