Sewage overflows were not the cause of three north Norfolk beaches losing their Blue Flag status, according to the Environment Agency.

East Runton, Sea Palling and Mundesley all lost their prestigious Blue Flags this year after a drop in water quality.

There were more than 300,000 combined sewage overflows (CSOs), an average of 824 a day, into waterways across UK last year – but the Environment Agency (EA) has said water companies are not to blame for Norfolk’s Blue Flag losses.

Instead, the government authority has said the most likely causes of contamination were bacteria from animals and birds, and high tides and bad weather stirring up bacteria from the seabed.

“We reviewed the monitoring results and could not find any evidence of sewage overflows which could have contributed to the elevated bacteria levels," an Environment Agency spokesperson said.

“We have carried out additional fieldwork to ensure there are no other sources of pollution.

"Based on the evidence, we consider the most likely cause of the high results were a combination of factors including high tides, several sources of bacteria - such as from animals and birds - and bad weather.”

The EA, which carries out around 90,000 water quality sampling visits from 13,000 different locations across the UK each year, previously said elevated levels of faecal matter and e-coli were behind the three downgrades.

Tim Adams, leader of North Norfolk District Council (NNDC), has vowed to win back north Norfolk's Blue Flags, but said it won't be possible again until 2025 under EA rules. 

READ MORE: North Norfolk leader vows to win back Blue Flag status for downgraded beaches

Eastern Daily Press: Tim Adams, leader of North Norfolk District Council (NNDC)Tim Adams, leader of North Norfolk District Council (NNDC) (Image: NNDC)

Mr Adams said although the agency has presented the "likely" causes for the decline in water quality, it cannot conclusively prove that sewage overflows have not contributed towards the issue. 

"They said at the time that they couldn't prove it wasn't sewage," Mr Adams said. 

"I'm afraid these changes in narrative appear incoherent to those who have followed this the closest. Theories blaming it on seaweed and dog fouling were also voiced without any real evidence. 

"What we do know is that sewage discharges were occurring at Gimmingham at the time of these issues due to a failure of oversight, policy, investment and long-term planning."

In May, privately-owned UK water companies pledged to spend £10bn by 2030 to cut the number of sewage overflows by up to 140,000 each year - promising the biggest modernisation of the nation’s sewer systems since the Victorian era.

READ MORE: The £10bn sorry: Water firms pledge to stop sewage spills in Norfolk's waterways

Currently, water companies are allowed to open CSOs to release rainwater and wastewater, including sewage, into waterways in cases of heavy rainfall. If not, sewage would overflow. 

Duncan Baker, North Norfolk MP, said the EA has assured him that all three of the Norfolk beaches have received twice the amount of water quality testing in the last year.

He said “virtually all the readings” have “demonstrated normal, healthy bacterial levels”.

Eastern Daily Press: Duncan Baker, North Norfolk MP, pictured at Mundesley beachDuncan Baker, North Norfolk MP, pictured at Mundesley beach (Image: Archant)

“To learn that these beaches are now being tested twice as frequently, and that all this year’s readings have come back normal, is extremely positive and puts these beaches on a very promising path,” Mr Baker said.

“I’m also delighted that my calls have been met, with the EA committing to DNA testing any findings of heightened bacteria on our beaches. It will give us valuable insight into how we can better safeguard them in future.”

READ MORE: Renewed call to end sewage dumping as MP defends Westminster vote

Mr Baker said Mundesley - one of the beaches which lost its Blue Flag - could be set to receive £2m of investment to install new storm tanks to reduce CSO spills, as well as additional monitoring equipment. 

The £10bn set to be spent by water companies to improve the water system hopes to transform 350,000 miles of sewer – a length that would stretch 14 times around the world.

There will also be a National Overflows Plan which promises greater transparency from water companies to allow them to be held to account for overflows.