Developers planning to build a 4,000-home garden city are adamant an idyllic stream near the estate will not become an "open sewer".

The huge Mountfield Park scheme in Canterbury has been met with numerous stumbling blocks, and two months ago councillors raised concerns about its wastewater management.

A decision on the project - which will see swathes of farmland between New Dover Road and Bridge be built on - was deferred by the city council's planning committee in September.

Fears over the quality and volume of water to be discharged into Lampen Stream, and questions as to who will be responsible for an on-site wastewater treatment works, were raised.

The Lampen flows through to Stodmarsh nature reserve, the Site of Special Scientific Interest (SSSI) which is suffering from high nitrate and phosphorus levels due to water pollution.

A host of housing developers across east Kent have been hampered by the water quality issues at Stodmarsh, with Mountfield Park suffering setback after setback due to the problem.

Following recent concerns at September's planning committee, Water Environment Ltd - a firm acting on behalf of developers Corinthian - has defended the proposals.

To begin with, wastewater will be carried through pipes and diverted to a holding tank before being transported away by trucks. Two tanker loads per day will ferry sewage out of the estate.

Speaking two months ago, Labour councillor Connie Nolan stressed: "Do the residents of Canterbury district realise that phase one is in essence a giant cesspit? I don’t think so."

But developers have hit back, affirming there will be no prolonged periods of human waste staying in silos and in cesspits.

Once 150 out of the 4,000 homes are built, a new "state-of-the-art" wastewater treatment works will be introduced on-site.

It will be built by Severn Trent Connect and paid for by Corinthian.

Treated water will pass through on-site wetlands for "polishing" where nutrients will be removed. It will then be discharged into surrounding ditches and Lampen Stream.

"Only water treated to an acceptable standard will flow into the Lampen, and this will be monitored continuously," fresh documents state.

"The stream will not become an ‘open sewer’.

"Water quality standards from the treatment works and polishing wetland will ensure that there is no adverse impact on the Lampen nor Stodmarsh.

"Natural England confirmed in their consultation response on September 16 that there was no objection to the proposed development."

As for the first phase of development when tankers will take foul water away, the developers say the method is "commonplace".

"Tankering of sewage is commonplace across the sector and there are several facilities within Kent which could be used without impact on any protected sites.

"No capacity issues are predicted."

Tankers taking away sewage will also be the method used at the redevelopment of the city centre's old Nasons site, which is set to be transformed into a pedestrian retail arcade, covered market hall and flats.

Cllr Connie Nolan is not convinced by either the Mountfield or Nasons plans.

She said: "The smell and disturbance caused by these sewage suction devices will transport the city back to the medieval period when human excrement was collected at night by night soil carts, euphemistically named 'honey carts'.

"The smell will not be of honey."