More than a thousand new homes are set to be built near Exeter Airport despite 67 objections from nearby residents.

The new development at Treasebeare Farm near Cranbrook, approved in principle by East Devon District Council's planning committee on Tuesday (28 February) will include a new primary school for over 400 pupils, as well as permanent pitches for travellers, sports pitches, shops, restaurants and a neighbourhood centre.

Just over 300 of the properties – a mix of one-, two-, three- and four-bedroom homes – will be classed as affordable.

However, work may not be able to start until concerns around sewage are addressed. Cllr Mike Howe (Independent, Clyst Valley) wants clarification from South West Water that it has the capacity to prevent a new development from worsening sewage troubles downstream from Cranbrook.

The approval in principle came on the day MPs criticised the utilities company in parliament in a debate initiated by East Devon MP Simon Jupp, who condemned South West Water's record on sewage discharges as "shameful."

Cllr Howe told the planning meeting: "We're not asking South West Water to tell us what they've got to do, they've just got to fix it. It is unacceptable in this day and age to allow raw sewage to come down and flow into people's homes, outside in the village streets where the kids play or anywhere else."

Cllr Olly Davey (Green, Exmouth Town) agreed that the water company needs to prove that the sewage system can withstand another housing development.

"I think I would suggest South West Water need to be able to demonstrate that they can cope with the sewage," he said. "Cllr Howe said that we don't need to know but I think we do actually. We need them to be able to show that they can cope. It seems as though every time we have an application, South West Water say: 'Oh yes, there's a sewer, you can connect to it.'

"I don't think we can make a condition that the residents of Clyst St Mary no longer find sewage coming up through their toilets, but I think we can ask that they are able to demonstrate that they have adequate capacity for the increased number of housing."

The new development will be heated using an extension to E.ON's energy centre, which is already used to heat homes in Cranbrook.

The energy provider has also come under fire, most recently for a heating outage in the town in December.

Cllr Richard Lawrence (Conservative, Whimple and Rockbeare) had some concerns. "E.ON are trying to do something that they've never done before," he said. "And they're not showing that they're capable of going any further – in fact they can't even look after the bit they've got at the moment.

"So I think before we go much further, we need to get some commitment from E.On that they are going to develop the system to make it robust and make it work. Because otherwise, we're just condemning people to a lifetime of misery and uncertainty as they've suffered over Christmas and the cold spell we just had."

This argument was challenged by Cllr Kim Bloxham (Independent, Cranbrook) who, while conceding that there had been failures, reminded her colleagues that some homes in Cranbrook were unaffected by that outage.

"It's wrong to say that E.ON are not capable of delivering district heating," she explained. "They are capable of delivering it; yes we've had some serious issues. I'm a resident there myself, I wasn't affected by the issues – not every resident was."

Following consultations with South West Water, East Devon Council will make a final decision about the development.