A senior housing inspector has warned Wiltshire Council to check the legal strength of its Core Strategy for the future of the county.

The council has submitted the far-reaching document, which lays out its blueprint for housing, employment and leisure up to 2026, to the Planning Inspectorate before it is examined in public later this year.

The most contentious part of the strategy relates to Chippenham and the shifting of an area for around 800 new homes and employment sites from the council’s previous preferred site in the east of the town, near Abbeyfield School, to the south at Patterdown.

Campaigners who have objected to the core strategy, say that the eastern development makes more sense for the town, is closer to the school, the Station and Wiltshire College, and finance for an eastern relief road to take pressure away from the busy town centre.

Two other sites, in the north near Langley Park and the north-east on the far side of the railway line, have also been identified. At least three will be needed to meet government housing targets.

The council’s own sustainability appraisal, submitted as evidence supporting the strategy, says the southern option is best and that an eastern relief road would make no difference Campaigners calling for the eastern option believe initial objections from villages such as Tytherton Lucas to the east of Chippenham led to it being discounted.

But Andrew Seaman, the senior housing and planning inspector, has written to Alistair Cunningham, the council’s director of economy and regeneration, raising doubts over the sustainability appraisal (SA) within the strategy and asking him to confirm that it is capable of withstanding a legal challenge. He writes: “There are a number of detailed queries raised by consultees in relation to the SA with which you will be familiar.

“These include concerns expressed in the manner by which the SA has equitably considered levels of development across the county over the plan period, the identification of strategic development sites, the potential need for contingency sites and the roles of settlements which include Swindon and Chippenham.

“I am seeking the council’s early view as to whether it remains satisfied that the SA is legally robust in the context of plan making.

“In this regard is the council satisfied that the SA is accurate, that it has taken into account appropriately relevant information, that it has considered the reasonable alternatives to the preferred options shown in the submitted Local Plan and fairly and that the reasons for discounting alternative options remain valid?”

Mr Cunningham dismisses the inspector’s concerns in his reply. He writes: “The council considers that the SA is legally robust in the context of plan making.

“The council is satisfied that the SA report is accurate and has taken into account relevant information.

“The SA report clearly shows what reasonable alternatives have been considered for each core policy, proposed strategic housing site and proposed strategic employment site.”

Robert Atwell, owner of estate agent Atwell Martin, is one of those supporting the eastern option.

He said: “The eastern option works because it utilises the school and the playing fields at Stanley Park. They are close for children to walk, and a link road would relieve congestion. “I have been talking about this for 20 years and I have yet to hear a convincing argument against it.”