Mr Witherby said the Big W's proposed Mittagong Marketplace was a classic example of the type of shopping centre development urban planners were trying to avoid.

"Edge of town" developments in towns such as Richmond, NSW, and Morwell, Victoria, had destroyed town centres without bringing the predicted benefits of lower prices and more competition, he said.

"The Market Place in Richmond, 200 metres from the main street, resulted in 24 vacancies in the main street."

Mr Witherby, a former planner with Shellharbour Council, is now a senior lecturer in Urban and Regional Planning at the University of New England's School of Humanities and Environmental Studies. He is currently working with the Department of Infrastructure, Planning and Natural Resources (DIPNR) in the area of non-metropolitan retail policy.

Mr Witherby said big retail developments aimed to replace pre-existing retailers by offering core services and parking to draw shoppers away from the town centres. Main street businesses were often forced to relocate to the shopping centre as a matter of survival.

Full story in Monday's Southern Highland News.