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Longer Reads

Is sewage pollution legal?

The legal and illegal pollution
of our rivers

Is it legal?

The short answer is "sometimes".

Water pollution is illegal unless it is permitted. Environmental Permitting (England and Wales) Regulations 2016.


So if you don't have a permit or stick to the conditions you are breaking the law but in the case of the water industry that does not mean that it will be prosecuted or even that it will be made to, or even asked to stop polluting illegally. Environment Agency Prosecution and Sanctions Policy, which only addresses the most spectacular offence and ignores the vast majority has made polluting profitable.

Here is an explanation of two ways that the industry pollutes illegally, by breaking permit conditions through polluting due to groundwater infiltration and secondly by failing to treat the required volume of sewage before dumping untreated sewage.

Here is an extract from a letter sent by Sir James Bevan, the CEO of the Environment Agency on 26 June 2020 to Cotswolds MP Sir Geoffrey Clifton Brown, asking questions on behalf of WASP and constituents.

Storming from sewage works and sewage pumping stations

Whilst it is undesirable, it is sometimes necessary for untreated sewage to be discharged to protect sewage backing up through the sewer network and flooding homes with sewage. This can only be carried out in line with permit conditions, which are designed to ensure the impact of any discharge to the environment is low. It can only be carried out due to rainfall or snowmelt. Discharges of untreated sewage due to groundwater infiltration alone are not permitted. 

Another example of the same statement, from EA Area Director, Julia Simpson to the Upper Thames Fisheries Consultative in July 2019. 

We expect water companies to identify and take action to minimise infiltration into their sewers.  Storm discharges due to excessive infiltration is not a genuine or permitted reason for a storm discharge.  We will take action in line with our enforcement and sanction policy where this is identified and causes environmental impact’. 

Anchor 1

Here is an extract from the Thames Water Groundwater infiltration management Plan, January 2021.

In recent years the foul sewerage system in the Bourton-on-the-Water catchment has become overwhelmed for weeks or even months at a time, following prolonged and heavy rainfall and raised groundwater levels.

In fact Bourton-on-the-Water overflowed for 1398 hours in 2019 and 1636 hours in 2020 on to the land treatment area which soaks into the ground and spills to the Windrush itself. There are no records published for the previously unknown and unpermitted overflow discovered by WASP at the sewage works itself. That was reported to the Environment Agency by WASP and the outcome remains vague.

Press releases and other documents are littered with groundwater infiltration as the cause of untreated sewage spills as if this is an excuse. It is not and the clarity brought to bear by WASP and others in this area is forcing the industry, the Environment Agency, and Ofwat to deal with an issue they have all ignored for 30 + years.

The second illegal spilling method is made by failing to treat the required amount. WASP has discovered that the permitting system used by the Environment Agency to license sewage works, in the Thames region at least, is quite disorganised with temporary permits in existence for many years and the requirements sometimes inadequate to ensure compliance.

However, many sewage treatment works do require a fixed flow rate to be transferred to full treatment before spilling is allowed. This was originally required to be in exceptional circumstances, a ruling reinforced by the European Court of Justice in 2012 but largely ignored by the regulators and therefore the water industry. Unfortunately, our regulators had already watered that down to when the sewage works was receiving more than 3 times its dry weather flow and our investigations show that even that has been diminished with some works spilling at 2 times the flow or even just over dry weather flow. This has happened as sewage works inflow has increased yet capacity has remained the same. The water industry has taken the extra revenue from more customers but often done nothing to expand treatment capability, falling back on overflowing and polluting to manage the increased volume. 

Fancy another?

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