How the climate crisis is polluting England’s rivers

Officials are raising alarm over how often sewage is getting pumped into England’s waterways - and the climate crisis is playing its part, Zoe Tidman writes

A ‘chemical cocktail’ of pollution is in many of England’s rivers, a new report says (Getty Images/iStockphoto)

Raw sewage is being pumped into England’s rivers and seas all too often - and this is something the government admits.

“Spills” - which prevent sewerage systems from becoming overwhelmed in times of heavy rainfall - happened on average 1,000 times a day and for a total of 2.6 million hours over the last year.

Officials say the current situation is “simply not good enough” as they warn over the dangers of sewage pollution in waters, which can harm both human health and the local environment.

The climate crisis could - at least in part - be driving this.

This is due to the overflow system for storms works. It is a crucial part of the country’s sewerage network, which is designed to be used in rainy weather and when the system is under pressure.

But while this is an important way of preventing backup in pipes and homes getting flooded, it also releases sewage into rivers and lakes before it has been properly treated.

The Environment Agency says this can affect water quality if it happens too often. In fact, MPs said earlier this year sewage was a key component in a “chemical cocktail of pollution” in many of England’s rivers.

Because of this, overflow systems are only meant to be used infrequently and in exceptional circumstances. However there have been suggestions they are being used more and more.

The MPs said use use of storm overflows appeared to be “increasingly routine as pressures on the sewerage network grow” in their daming report from January.

The government - who released new proposals on how to tackle sewage discharges in waterways on Thursday - also said spills were happening at an “unacceptable” frequency.

It said an increase in extreme weather events was one of the reasons for this. These were putting extra pressure onto sewerage systems and therefore triggering its overflow systems more often.

One of the reasons for this was the increase in extreme weather events, which was putting added pressure on the sewerage system.

This is where the climate crisis enters: it is not only causing hotter temperatures, but also heavy rainfall - which triggers the overflow systems - to happen more often.

Warmer temperatures means the air can hold more moisture. So when it does rains, it pours.

Professor Nigel Watson from the Lancaster Environment Centre said the climate crisis was exacerbating the risks to public health and wildlife from poor water quality due to its impact on overflow systems.

“Discharges of untreated sewage have become increasingly commonplace as a result of more frequent intense rainfall and storm events, despite those discharges only being permitted by law in exceptional circumstances,” he said.

However, it is not the only factor that has been linked to overflow systems being relied on more, with a growing population and more urban development putting pressure on the sewage network as well.

Even so, heavy rainfall - the very thing overflows were set up to deal with - is certainly playing its part too.