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CPRE Sussex Director’s column written for West Sussex Gazette, May 2024

2nd June 2024

Across West Sussex too many new home developments are going ahead without adequate sewerage infrastructure despite protests by local councils and residents.

This has led to well-documented problems including poor drainage, hydraulicly overloaded sewers, sewage flooding into people’s homes and gardens and storm sewage overflows into environmentally sensitive areas.

Discharges of untreated sewage are also far more widespread than can be gauged from designated overflows alone.

A Flood Watch team assembled in Middleton-on-Sea recorded sewage flooding from manholes along the main sewer in the parish 17 times in its first year alone. This was not reflected in Southern Water’s records implying considerable under-reporting of diffuse sewage flooding.

What is worse, these problems are only set to increase if we do not act now.

Risk and vulnerability assessments for the Arun & Western Streams River Basin Catchment Area show the percentage of the population with “very significant risk” of sewer flooding due to hydraulic overload is set to increase from 6.9% in 2020 to 41.4% in 2050.

The percentage of people at “very significant risk” in the Adur & Ouse Levels Catchment Area is set to increase from 36.2% to 87% in the same period.

CPRE Sussex has launched a new campaign to tackle this unacceptable situation.

We want to see councils make adequate sewerage infrastructure a prerequisite to development. No sewer upgrade, no permission to develop or occupy new homes.

To achieve this goal, we are calling on councils to make use of so-called Grampian conditions.

Grampian conditions are based on the legal case Grampian Regional Council v City of Aberdeen (1984). In essence, this case established that the requirements of a condition can preclude the implementation of development.

Examples of such conditions include reinforcing the sewerage network, extending treatment capacity at a sewage works, improving surface water drainage or reducing overflows to environmental waters.

While the primary aim is to make sure the necessary infrastructure is built, this approach is likely to also reduce speculative development.

The campaign launch followed a seminar on new housing development and sewerage infrastructure hosted by Middleton-on-Sea Parish Council at the end of 2023. The seminar was attended by representatives from 25 councils in Sussex and saw strong support for the introduction of Grampian conditions.

Currently, the environmental objectives of the National Planning Policy Framework (NPPF) are too often over-ridden by Planning Inspectors in the consideration of development appeals.

The NPPF’s presumption that development proposals should be considered sustainable has resulted in many speculative development proposals that clearly seek to bypass local planning controls and flagrantly disregard the natural environment.

Grampian conditions offer an opportunity to put controls back into the hands of local and neighbourhood planning authorities and address sewerage deficiencies before allowing new development.

Want to know more about Grampian conditions and the issues caused by sewerage in Sussex? Visit