Residents have spoken of ‘huge disappointment’ after divisive plans for a sewage treatment plant to serve almost 6,000 new homes were approved following an appeal.

Ashford Borough Council (ABC) refused the proposal for the facility at the sprawling Chilmington Green housing development, in Shadoxhurst, near Ashford, in May.

But last month developers Hodson Developments appealed the authority's decision to reject the plant to the Planning Inspectorate, arguing a solution to treating wastewater was a vital part of the already-under-construction garden town.

Problems relating to the impact of wastewater on the Stodmarsh Nature Reserve near Canterbury prevented the new estate from using the existing Southern Water facility.

The protected beauty spot has been affected by wastewater run-off from developments across east Kent causing high levels of harmful nitrate and phosphate nutrients.

As a result, Natural England rules insist developers must ensure all schemes in the River Stour catchment area - stretching between Ashford, Canterbury and Hawkinge - are “nutrient neutral”.

This means developers must either install an on-site water treatment facility or offset the impact by providing mitigation measures elsewhere, such as wetlands.

And now, the planning inspector has approved the plans, with a number of conditions.

An ABC spokesperson said: “The council acknowledges the inspector’s decision - we particularly note she has imposed a number of planning conditions on the developer to mitigate against the concerns expressed by residents and the planning committee, and that they must be met before any works can take place.

“Another key point to note is that works cannot start until an Environmental Permit has been issued by the Environment Agency (EA).

“We will therefore ensure that this condition, which the planning inspector has also insisted the developer obtains in advance of any works beginning, is met.”

Originally, the latest phase of the Chilmington scheme faced mass objections from locals, with almost 300 registering their views with ABC.

It was feared the facility would leave neighbours dealing with “intolerable odours”.

Resident Andy Geer says everyone is “extremely disappointed” with the decision.

“It's been made very clear that the residents are not being listened to,” he said.

“I suppose the saving grace is it still has to get Environment Agency approval. So it's not 100% yet. We're going to be lobbying the EA and making sure that at least they follow the correct procedure.”

ABC rejected the proposal on the grounds of pollution, additional noise and odour and visual harm.

However, Hodson Developments believes the local authority lacked sufficient evidence to reinforce its reasons for refusal.

Concerns were also raised over the lack of work on upgrades to nearby Chart Road – a Section 106 requirement of the original 5,750-home application.

The project is supposed to provide vital improvements to the section of the A28 between the Matalan and “Tank” roundabouts in Ashford.

However, Hodson previously submitted an appeal to the planning inspectorate that seeks to vary or delete a significant number of its current requirements in its Section 106 agreement. But further details have not been published.

Money for the highway changes is supposed to be available when 400 homes are occupied - currently 300 are.

Hodson was approached for comment.