A year-long ban on housebuilding which has halted work on thousands of properties in large swathes of Norfolk is set to finally be lifted next month.

All new housing schemes in vast areas of the county, including high profile projects like Anglia Square, have been blocked since last March over claims they would contribute to pollution in local waterways.

But new measures are set to come into force next month which officials say will allow work to start going ahead again.

Eastern Daily Press: Natural England says nutrient neutrality is necessary to prevent algal blooms on the Broads.Natural England says nutrient neutrality is necessary to prevent algal blooms on the Broads. (Image: Archant)

The halt was ordered last year by Natural England, in response to fears that new housing was contributing to rising levels of nitrogen and phosphates in the Norfolk Broads and River Wensum, through things like wastewater from dishwashers and washing machines.

Such nutrients reduce oxygen in the water and make it harder for aquatic species to survive.

Ever since, council officials and conservation experts have been trying to come up with a way to reduce the impact of nutrients while allowing new homes to be built.

Their solution - which will be introduced in April - is a new mitigation scheme allowing housebuilders to 'offset' the impact of their developments by buying 'credits' to fund measures that will minimise the impact of the pollution.

The credit system is being launched by five Norfolk councils, in conjunction with Anglian Water.

Eastern Daily Press: Phil Courtier, director of place at South Norfolk and Broadland councilsPhil Courtier, director of place at South Norfolk and Broadland councils (Image: Simon Finlay Photography)

It will operate in a similar way to schemes used for carbon emissions, where businesses can buy the right to emit a set amount of CO2.

Full details of how it will work have yet to be announced.

Phil Courtier, a senior council official, said: “We are intending that joint venture effectively goes live next month with the intention to trade as soon as possible. 

“At the same time, a significant amount of work is going into securing a pipeline of projects, where that mitigation can be acquired."

Mr Courtier said the group will not own the mitigation measures but will distribute the credits generated by various schemes, which could include things like the creation of reed beds to 'trap' nutrients.

He announced the news at a hearing to discuss the Greater Norwich Local Plan (GNLP), which is assessing where homes should be built in South Norfolk, Broadland and Norwich between now and 2038.

The meeting was held by the government's Planning Inspectorate, which has been looking into the 'nutrient neutrality' issue and its impact on the wider 50,000-home blueprint.

Local plans are supposed to ensure developments are supported by the necessary infrastructure and make it more likely that planning applications in those places would be approved.

He told the inspectors that there was likely to be a limited number of credits generated in the first couple of months, suggesting enough to cover around 300 homes. 

However, he expected this would accelerate as time went on, while larger schemes of 600-plus houses would be able to create their own mitigation measures, through things like water treatment.

“We are confident that circa 60pc of the growth that is in this plan could be met by developers providing their own solutions to these schemes,” he said.

Oliver Louise from Natural England - which has to sign off on the credit scheme - told the inspectors it supported the mitigation scheme in principle but said it would “come down to the detail” and what can be practically delivered.

“We really need to see full details of the scheme and the credits and exactly how it will be implemented before we can comment in detail," he said. 

The inspectors also heard about a separate mitigation scheme developed by Norwich City Council, which is just designed to help unlock the Anglia Square development.

An application to redevelop the key city site is expected to be heard by a planning committee late next month.