New interactive map shows London areas worst hit by sewage overflows

River Thames
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Thousands of water pollution incidents were not immediately seen to in London since 2018, new figures show. This news comes alongside a new map, showing where exactly in London sewage overflows occurred last year.

A freedom of information request by RADAR shows the Environment Agency is attending fewer incidents across England than before the pandemic. The figures show there were 2,611 water pollution incidents in London between 2018 and 2023, just 451 of which were visited immediately by Environment Agency staff.

This means they were attended within two hours of a report coming in, or within four hours outside of the normal working day – a definition set by the organisation. Of the 2,160 of those not visited immediately, 20 were category two incidents, which are classed as having a 'significant' impact. You can view the full interactive map below.

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The remainder were category three, meaning they were judged as having a 'minor or minimal' impact on the environment - but it is unclear whether these incidents were checked at a later date or not at all. The Environment Agency has said there are many reasons for not visiting pollution incidents straight away. It said some incidents can be handled remotely or instead through emergency services, adding some reports come through some time after an incident has taken place.

Nationally, the agency attended 36 per cent and 34 per cent of incidents within the timeframe in 2018 and 2019 respectively. This dropped to 20 per cent in 2020, only climbing back to 27 per cent last year.

An Environment Agency spokesperson said: "We assess and record every incident report we receive – between 70,000 and 100,000 a year. We respond to every incident and always attend those where there is a significant risk." Despite this, seven 'major' and 88 'significant' events were not attended within the agency's target timeframe in 2023, a rise on three and 58 incidents respectively the year before. There were 351 water pollution events registered in London last year, 98 of which were linked to a water company.

Greenpeace policy director Dr Doug Parr said there was an urgent need for water regulators to be given "more staff, more money and more power", but that the last Government did not invest in regulation. He said a fall in standards in the water industry was matched by "a decline in the bodies enforcing those standards". Water companies were responsible for more than 2,300 incidents in 2023.

A spokesperson for industry body Water UK said: "No pollution incident is ever acceptable and this is why water companies have proposed to invest £105 billion – a near-doubling of current levels – to upgrade our network. We need Ofwat to approve our plans in full so we can get on with it."

The Environment Agency also said: "We take our responsibility to protect the environment very seriously and will always pursue and prosecute companies that are deliberately obstructive or misleading."

Their spokesperson continued: "While criminal prosecutions can be lengthy processes, since 2015 we have concluded 63 prosecutions against water companies securing fines of over £151 million. Last week’s Water (Special Measures) Bill will make it easier for us to take enforcement action and build on our ongoing work to deliver our biggest transformation in the way we regulate."

The agency said it is recruiting more staff, increasing compliance checks and water company inspections, and visiting more water pollution incidents.

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