Ways of reducing the impact of 400 new homes at Hatchfield Farm on transport, education and racing were explained to councillors at a special meeting on Wednesday.
Forest Heath District Council decided to open the ‘member briefing’ on Hatchfield Farm and Red Lodge developments to the public, though only five attended.
Councillors were told not to discuss planning issues.
Lord Derby’s planning consultant Bob Selwood said the original application for Hatchfield Farm, rejected in 2012, had been for 1,200 homes and 36,000sqm of employment.
The new plan was for 400 homes, of which 120 would be affordable and 70 per cent of those would be for rent.
He said their transport assessments had been audited by the Highways Agency and Suffolk County Council and the plan was to put traffic lights on the A14/A142 junction to improve north-south traffic flows by removing vehicles waiting to turn right.
There would also be a new foot and cycleway on Fordham Road and they would contribute to horse crossings planned closer to the town centre.
He said they would give the land and £1.78 million for a new school as the county had requested that day.
He pointed out the strength of racing and added: “Hatchfield is only five per cent of the current housing stock in Newmarket. Will that really threaten the industry?”
Crest Nicholson will also give land and £3.44 million for a new school at Red Lodge, in its plan for 371 homes on three sites totalling 18.13ha, mostly to the north of the village.