Controversial plans for a waste energy plant in the Norfolk countryside may have been dealt a significant blow after road chiefs called for them to be refused "without hesitation".

The highways department at County Hall has made a case against an anaerobic digester (AD) plant in Bressingham, near Diss, raising "significant concerns".

In a report to South Norfolk Council, officers warned the plans are likely to be "detrimental to highway safety".

But, Deal Farm Biogas, one of the companies behind the plans, insists safety would be better monitored if the plant went ahead.

The AD plant uses organic waste and crops – such as manure or maize – to create biomethane that can be used to produce power.

Two large domes have already been built on the site. They were constructed under a previous planning application that is now obsolete.

In his report, Jon Hanner, a highways department officer, said: "The highway network serving the site is considered to be inadequate to serve the development proposed, by reason of its poor alignment, restricted width, lack of passing provision, substandard construction [and] restricted forward visibility.

"The proposal, if permitted, would be likely to give rise to conditions detrimental to highway safety. Contrary to development policy."

Previous planning applications in Norfolk have been turned down on similar highways grounds, including a set of waste lagoons in Seething.

A spokeswoman for Deal Farm Biogas said the Bressingham farm was the ideal site because it is where the feedstock is produced and stored.

The company argues this will lead to a reduction of 400 two-way movements each year.

She dismissed calls for the application to be on a main road, arguing this failed to acknowledge that material from Deal Farm would still have to be transported on the same road network.

She said: "By delivering the AD plant scheme at Deal Farm, highway safety is actually better monitored than if the plant is not operational.

"The delivery of the AD plant would result in better transport management on the local network as we can be conditioned on various highway safety points."

Objections to the plans have also been submitted by almost 250 concerned residents, as well as Liz Truss the South West Norfolk MP, Richard Bacon the South Norfolk MP and the Campaign to Protect Rural England.

Twelve letters of support have been submitted.

A history of the AD plant

The plant has been controversial since a previous planning application was approved in 2015.

When locals had begun to hope the scheme had been forgotten, development finally got under way in 2018.

But as the plant was being built residents began to voice concerns that it was "completely changed" from the approved scheme.

By October 2021 the developers were instructed by South Norfolk Council to stop work on the site, with officers questioning the legality of the development.

Deal Farm Biogas (DFB), the company behind the plans, then submitted a new planning application. But residents continued to raise concerns.

Their campaign caught the attention of the local MP Richard Bacon and later South West Norfolk MP Liz Truss, who joined them in their objections.

DFB then pulled their application in June, before submitting a revised and scaled-back design.

But communities surrounding the plant have continued to raise objections.