The storm overflow in Dickleburgh releases into a tributary of the River Frenze, which flows into the River Waveney and is next to the Otter Trust's Dickleburgh Moor site.

Since the start of the year, there have been 1,073 hours of spills from the overflow, which is linked to the Anglian Water sewage treatment works.

The sewage treatment works can be seen in the distance, where a storm overflow releases wastewater into the stream (Image: Owen Sennitt)

The issues in Dickleburgh have led the water firm and the Environment Agency to conduct investigations into why the system is being overwhelmed, which has found high levels of infiltration into the sewerage system.

The onslaught of wastewater is causing concern for the Otter Trust, which manages a wetland area adjacent to the sewage works, who fear the pollution could harm the rare plants, insects and other creatures that live at Dickleburgh Moor.

Dickleburgh Moor (Image: Owen Sennitt)

Ben Potterton, a trustee for the Otter Trust, said: "The nutrients from the sewage can cause big algae blooms, which can kill rare plants, amphibians and insects.

"We accept we are on a floodplain, which floods every three to five years but what we do not accept is sewage coming through. It is quite horrific.

"The river ultimately flows into the River Waveney and is in the same catchment where water is used for drinking water by Essex and Suffolk Water."

Ben Potterton, trustee of the Otter Trust in Dickleburgh (Image: Owen Sennitt)

Mr Potterton said he is speaking with Anglian Water about creating a reed bed system on part of the reserve to help clean the water and absorb any flooding but the Trust would need funding to do so.

Strangely, downstream the River Frenze, which continues onto the Waveney, currently has low flows but further upstream water is backing up and is causing flooding.

Ben Potterton inside the 1960s pumping station, which is used frequently to prevent the site from being flooded with wastewater (Image: Owen Sennitt)

The Otter Trust is having to pump out floodwater regularly and recently was hit with a £9,000 bill for the energy costs of using the 1960s pumping station.

The money to pay for this comes from donations, leaving the charity with less money for other projects.

As well as the risk of wastewater coming from the storm overflow, a recent burst water main to the north of the site led to major flooding.

The stream where wastewater flows from the sewage treatment works in Dickleburgh (Image: Owen Sennitt)

Mr Potterton said the Environment Agency was concerned about contamination from chlorine entering the freshwater, which would harm wildlife.

Anglian Water and the Environment Agency have recently conducted an audit into the site.

A water leak on Norwich Road this week, with some very grey coloured water entering the Dickleburgh Moor perimeter ditch. The Otter Trust had to pump out the water to avoid it entering its ditch system. (Image: Dickleburgh Moor Nature Reserve)

The water firm said this revealed the site is struggling with "high levels of infiltration," which is causing the STW struggling to process "very high flows".

Nearly 500 properties have been visited to try and identify misconnections, where surface water is connected to foul sewers.

The 1960s pumping station, which is used frequently to prevent the site from being flooded with wastewater (Image: Owen Sennitt)

Inspections found 138 points of infiltration into the sewer system, 26 of which were classified as "running or gushing", meaning there is a constant flow of water entering the sewer.

All but one of these infiltration points will require specialist repairs.

An aerial view of the sewage treatment works in Dickleburgh (Image: Google Maps)

A spokeswoman said: "We believe that we have found enough contributors to drastically reduce the impact at the water recycling centre and the pollution risk upstream in the catchment.

"The remedial works will be prioritised based on impact to ensure we target those with the highest impact first."

A spokeswoman for Essex and Suffolk Water added: "Our water goes through thorough treatment processes and is sampled and monitored to make sure it is high quality, before it reaches customers’ homes.

"We work in collaboration with many partners to help improve the quality of the River Waveney and will continue to do so."

Downstream in the village, the stream's flow is lower than upstream (Image: Owen Sennitt)

The problems in Dickleburgh have been faced elsewhere in Norfolk.

In Grimston, near King's Lynn, there have been sewage spills for a total of 512 hours this year.

The latest annual results for the site showed 1,837 hours of spills in 2024.

Dickleburgh Moor (Image: Owen Sennitt)

Anglian Water has said misconnections, high groundwater levels and infiltration into the sewer system is to blame for the system being overwhelmed.

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