Developers will commit "environmental vandalism" by felling trees to make space for a wetland on a new housing estate, say concerned councillors.

Mulberry Homes and GSE have been given detailed planning permission for the first 144 properties on the former Ashford International Truckstop site on Waterbrook Park.

But the scheme will result in the loss of 3.6 acres of woodland in the south-west corner of the site to allow for the wetland to be built.

Developers say the area will help mitigate nitrate pollution as any new scheme within the River Stour's catchment area must show 'nutrient neutrality' to protect the conditions at Stodmarsh Nature Reserve.

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

As a result, rules set down by Natural England insist developers must ensure all schemes in the River Stour catchment area are 'nutrient neutral' - either by having an on-site water treatment facility or offsetting the impact by providing mitigation measures elsewhere, such as wetlands.

But councillors on Ashford Borough Council's (ABC) planning committee raised concerns over the proposed loss of trees when they met to discuss the Waterbrook project last week.

Bosses say replacement trees will be planted around the edge of the scheme, close to the new home of Ashford International Truckstop.

But former ABC deputy leader Cllr Paul Bartlett (Con), who represents the area, said: “It’s a great shame this application envisages losing 1.48 hectares [3.6 acres] of established and mature woodland, as new planting elsewhere will take years to develop.

“While I appreciate nutrient neutrality is necessary, the need to have it on site is causing the unnecessary destruction of an established woodland, when the better option must be off-site mitigation.

“This application highlights the potential damage that we can see being done to well-established mature countryside to protect Stodmarsh.”

The project forms part of a wider development of 364 homes which was approved by ABC in December.

But Cllr Bernard Heyes (Con) shared Cllr Bartlett's view, saying the developers should have instead put wetlands or other mitigation elsewhere.

“I’ve got grave concerns about this,” he said.

“I would imagine it takes hundreds of years for a woodland of this nature to be established and all the consequences of that.

“Putting trees round lorry parks and putting out some bat boxes isn’t going to touch it, we all know that don’t we, it will not replicate anything like the amount of wildlife on this site.

“This area used to be rural, but now it’s being urbanised, surely little pockets of woodland we should try to maintain for the environment and for the people who live in the facility.

“I think it boils down to environmental vandalism personally."

James Waterhouse, a planning agent on behalf of the developers, told the meeting that construction had been “stuck like so many other stalled schemes in the area” due to the Stodmarsh issue.

He added: “None of this is anybody’s fault, the neutrality position has caused and continues to cause so much harm to the area, but it's so important that this site has the opportunity to deliver the infrastructure.

“This site should be part of the solution but it’s become part of the problem.”

Planning documents show the new wetland does not provide enough mitigation for the entire 364-home estate, hence the application for only 144 homes came forward.

During the meeting, a planning officer from ABC, which is led by an Ashford Independents/Green Party coalition, stressed the authority’s arboricultural officer had no issue with the plans to fell the trees, which sit alongside the East Stour river.

And Cllr Ray McGeever (Ashford Independents) had no issue with the proposals, saying the area was more “scrubland” than woodland.

“Really from scrubland to developed biodiversity I would suggest we’re actually complementing this development,” he argued.

The plans also include a “farmstead” building envisioned to host a shop or cafe for residents of the new development.

Planning chiefs recommended approval of the plans, explaining the scheme consists of a “mix of two, three and four-bed units, and also 15 affordable dwellings which is 10%”.

Normally a development of this size in the borough would need to be at least 30% affordable homes, but a “viability appraisal” by the developers found this would diminish their profit too significantly, so the quota was reduced to 10%.

The affordable homes to be provided are under shared ownership schemes, rather than social rent, to which Cllr Kayleigh Brunger-Randall (Con) said: “I’m not very happy with that, I think we need more social rent not just shared ownership, especially on a large housing estate of 144 and I think that’s been overlooked.”

Despite this, the committee voted to approve the scheme, with eight votes in favour and three against.

Later this year, ABC and Canterbury City Council (CCC) will be establishing a joint company to sell “nutrient credits” to developers, to fund schemes like new wetlands to offset pollution in Stodmarsh.

Find out about planning applications that affect you by visiting the Public Notice Portal.

Set to be called Stour Environmental Credits Ltd (SEC), developers will purchase the credits from the company, which will then use the proceeds to help fund projects to mitigate the pollution caused by building new homes.

The measures also include water companies improving works to water treatment facilities, upgrades to septic tanks and new connections to treatment works.

SEC will then issue certificates to developers to confirm that they have bought credits and contributed to mitigation, which would be submitted with planning applications to allow them to proceed.