Thousands of sewage overflows in Northumberland last year

Storm overflows normally happen when the sewage system is at risk of being overwhelmed – such as after a heavy rain, or during higher levels of groundwater.

In these cases, water companies may need to release excess water and sewage into rivers and the sea, to prevent water backing up into the streets and people's homes.

This has an impact on the quality of our natural water sources, with some charities alleging storm overflows are being misused and under-reported.

Figures from the Environment Agency show storm overflows were used 7,382 times within Northumberland's local authority boundaries in 2022, discharging for a total of around 33,145 hours.

Of these, 7,299 were from Northumbrian Water's network.

These figures may not provide a full picture of the amount of water pollution in the area – Northumberland may also be impacted by overspills from areas it shares water sources with.

The Rivers Trust said it was particularly concerned by storm overflows being used during hot periods – a risk as England faces a heatwave this week.

Tessa Wardley, director of communications and advocacy at the charity, said: "Discharging untreated sewage in dry weather is bad for both human health and river health – lower river flows mean more concentrated pollutants at a time when more people want to enjoy their rivers."

"Although a problem in their own right, these discharges are also the ‘canary in the coalmine’ pointing to greater problems in our sewerage and river systems. This could be blockages in the system, groundwater seeping into broken pipes, misconnections, or just poor management choices," she added.

She urged "robust, urgent action" on sewage and river management to help tackle the climate crisis and threats to biodiversity.

The three companies providing water to the area – Northumbrian Water, Yorkshire Water and United Utilities – were responsible for 153,215 spills between them.

Water minister Rebecca Pow said the amount of sewage pumped into rivers is "utterly unacceptable", adding the Government has a plan to tackle pollution.

She said: "Targets set by the Government to reduce storm overflows are very strict and are leading to the largest infrastructure programme in water company history – £56bn over the next 25 years."