Concerns over increasing road congestion dominate the thoughts of councillors following the latest plans for Chilton Woods.
Suffolk County Council submitted its application for the 1,100-home scheme on the outskirts of Sudbury last week.
Members of the public will be able to view the plans from January, with a public consultation to follow, although some councillors have already seen the plans.
Sudbury town councillor John Sayers, who has recently been to look at the site, said: “It’s quite an extensive and important development.
“I’ve felt all along it’s a bit of a massive development on the fringe of Sudbury but we do need development. We must not stagnate.
“But I feel it will rather impose on Sudbury and will have a serious impact on people’s quality of life.”
He is particularly concerned about congestion, especially the impact on visitor numbers if the town centre traffic worsened.
Mr Sayers said the county council was focused on the site and was sure it would be developed.
He said it was vital the infrastructure, such as traffic measures and the building of a new waste plant, were completed in line with housing being built and occupied.
Mr Sayers was supportive of the business and retail site in the plans, hopeful of a hotel being built on the development.
The site lies within the parishes of Chilton, Acton, Sudbury and Long Melford and is allocated for development in Babergh’s adopted Local Plan for the period 2011-2031.
Chilton Parish Council vice chairman Keith Shapley said he had not yet viewed the plans but shared Mr Sayers’ concerns over traffic.
Long Melford Parish Council chairman Jayne Lines had also not yet seen the latest designs.