It will take decades and millions of pounds before the release of sewage into Norfolk's rivers and seas at times of heavy rain is eliminated, water chiefs have admitted.

Bosses from Anglian Water were quizzed by county councillors over pollution incidents, where they were urged to speed up efforts to reduce discharges from storm overflows.

Water company chiefs defended their attempts to reduce how often raw sewage is released through the overflows - and told Norfolk County Council's scrutiny committee the public needs to play its part to stop them having to take such action.

Pressed on how long it would take to get systems in place which did not rely on such discharges during periods of heavy rain, Dr Robin Price, Anglian Water's director of quality and environment, said it could be done "within decades".

Eastern Daily Press: Steve Morphew, chairman of Norfolk County Council's scrutiny committeeSteve Morphew, chairman of Norfolk County Council's scrutiny committee (Image: Denise Bradley)

In response to a question from Steve Morphew, scrutiny committee chairman and Labour group leader, Dr Price said: "If we continue to invest in our measures to ensure we are operating at 100pc of the time, we can solve the issue together and I think we can do that within decades."

Storm overflows are used when there is too much water in pipes, such as after heavy rain. Safety release valves open to reduce the pressure, releasing excess, untreated, water directly into rivers or the sea.

Permits, issued by the Environment Agency, allow that to happen in certain conditions, such as heavy rainfall, to prevent foul water backing up into homes and businesses. But it is illegal at other times.

Dr Price said Anglian Water was trying to eliminate the "legacy" of storm overflows, such as by creating more wetland to prevent surface water run-off heaping pressure on pipes.

He said Anglian Water was investing £800m in the region between 2020 and 2025, with £200m directly into addressing storm overflows.

Data on how many incidents there were in 2022 is not yet publicly available, but Dr Price said there had been a "significant reduction" in frequency and duration of storm overflow use.

He said that in 2018, each of the water company's storm overflows was activated an average of 38 times, while provisional figures for 2022 suggested it had dropped to an annual average of 15 times.

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Dr Price said, along with pressures from surface water and breakages, blockages were an issue triggering storm overflows  - which the public could help prevent.

He said: "Fundamentally, we are putting the wrong stuff down our sinks. Things like fat and wet wipes. We find nappies, we find walking sticks, we find all sorts.

"Our sewer network is open to abuse. People lift manholes and we have a real fly-tipping problem."

Eastern Daily Press: Anglian Water bosses have urged people to be careful what they flush into sewers to prevent blockages like this oneAnglian Water bosses have urged people to be careful what they flush into sewers to prevent blockages like this one (Image: Anglian Water)

Leaks from sewage have made headlines recently, with a spill at Mundesley and concerns over a possible discharge at Gorleston.

Eastern Daily Press: Mundesley BeachMundesley Beach (Image: ianwool)

But Green county councillor Jamie Osborn said an historic lack of investment had contributed, while dividends paid to Anglian Water shareholders could have been better used to improve infrastructure.

Eastern Daily Press: Green county councillor Jamie OsbornGreen county councillor Jamie Osborn (Image: Jamie Osborn)

Dr Price said shareholders had not received any dividends for five years between 2017 and 2021 and investors had reinvested £200m.

READ MORE: Mundesley Beach closed after burst pipe sewage leak

The grilling by councillors came just hours after a House of Lords committee said Ofwat, the regulator for England and Wales, had failed to ensure water companies had invested sufficiently in infrastructure.

The committee said it and the Environment Agency must do more to hold polluters to account through penalties and prosecution.

It also emerged at the council meeting that Anglian Water could face enforcement action over potentially illegal storm overflow discharges into the River Wensum in Norwich.

Eastern Daily Press: The river Wensum in NorwichThe river Wensum in Norwich (Image: Archant)

Rachel Storr, from the Environment Agency, confirmed an investigation was under way over four potential breaches in 2020, which could lead to enforcement action against Anglian Water.