Three new schools have just opened in Swindon. The £25 million Deanery Academy welcomed its first pupils with a flag-waving ceremony last week, with reception classes at William Morris and Badbury Park primary schools starting yesterday.

Wichelstowe will also be getting a new primary school next year, situated next door to The Deanery.

But how do new schools come about? How are they planned? Who gets to decide where they go, and who will run them?

Gareth Cheal, Swindon Borough Council’s education place planning manager, and Emily Heaton, the council’s strategic school admissions manger explain that the process has become rather more complex in the last couple of decades.

“If you go back decades then school were run by the local education authority, which would have been Wiltshire County Council, or now Swindon Borough Council," said Mr Cheal. "The council would decide where it needed a school and would go about planning it, setting it up and running it.”

While the borough council still runs some schools in the borough – about 20 out of 80 across Swindon – new ones have to be run as academies or free schools. This means they are not under the LEA’s control in terms of funding, curriculum or staffing.

But it has quite a lot of say in where new schools might be opened.

Mr Cheal said: “When we know there’s going to be a need for new school provision, we invite academy trusts or free schools to make a bid.

“For many years new schools here would be either run by the Diocese of Bristol or the White Horse Trust. Basically we’d select one for one school, and the other for the next, and we could have carried on like that for years, so this time we went out and deliberately tried to get more trusts interested. The diversification of provision is important and it can help drive up standards.”

While The Deanery in Wichelstowe is part of the Diocese of Bristol Trust, both William Morris, at Tadpole Garden Village, and Badbury Park are run by the Blue Kite Academy Trust.

Mr Cheal said: “When they are selected, they then make a bid for approval from the Department for Education and the funding that comes with it.”

That bidding process all takes years, let along the construction work needed before a school opens its doors.

And they don’t come cheap – a new two-form entry primary costs just under £8m to build, with a secondary coming in at £30m.

But planning where new schools should go to best meet a need starts years before that, with Mr Cheal and his colleagues analysing years of data.

He said: “We know from other areas of the council, in children's services, where babies are being born, where the population is growing, where there might be an influx of young families – such as in the town centre with the growth of the Goan community.

“So we have three or four years of data about what’s happening, and it gets easier for secondary schools, because we have even more data about the children who are coming up from primary schools.

“And obviously if you know there are major areas of expansion, like Badbury Park or Tadpole Garden or the New Eastern Villages, you know that there are going to be needs for more schools.”

There’s a formula for working out how many places are needed.

Mr Cheal said: “For primary schools its 0.37 places per house – so for every 100 houses, we need 37 primary places. For secondary schools it’s 14 places per 100 houses.

“We try to make sure there’s always a slight surplus of places as well, with an eight per cent surplus at primary level and six per cent at secondary schools, so we know there will be enough places for everyone in the borough.

“It’s important to have that flexibility from the start as it’s very difficult to go back and retrofit extra capacity into a school once it’s up and running.”