The state government has promised that the future Wilton New Town will be home to a new school, healthcare facility and a public transport interchange.
But Wollondilly councillors want to know precisely when these projects will be delivered.
Planning and Public Spaces Minister Rob Stokes recently announced that the rezoning process for the Wilton Town Centre development would be fast-tracked, bringing thousands of new homes to the growing region.
However, councillor Judith Hannan raised a notice of motion at last week's council meeting calling on the Department of Planning to reveal the 'trigger points' that would reveal the department's delivery plans for water, schools, hospitals, transport and more.
Cr Hannan said the Department of Planning's brochure for Wilton outlined that in five years when more than 5000 homes have been built, land has only been allocated for the future school and community facilities.
"There's no delivery of the actual infrastructure," she said
"When we move on to the 10 year mark, the estimated dwellings built will be 9784, and we look down the list of things, and yes there are some roads and some cycleways - but it says land for future education purposes and healthcare facility land.
"When we move out to the year 2041, when there are over 15,000 houses, it still says land for future educational purposes.
"In all those years, it does not declare when we are going to get a school, a medical facility, or the appropriate transport.
"There are no plans for all of that through the next 20 years, but by then, we'll have 40,000 people living there."
Cr Hannan said the Department of Planning did a housing forecast which predicted Wilton would gain 280 homes over the next five years.
"Two-hundred-and-eighty homes over the next five years, although we've got residential land rezoned for 11,000 lots and we've got 1600 lots already underway and 250 currently registered lots," she said.
"And nowhere does it say when they are going to deliver the water plans, the hospital, the school and transport."
The Wilton Town Centre precinct will include 1600 dwellings, 17 hectares of employment land that could support approximately 4700 jobs and 39 hectares of environmental conservation land.
Councillor Noel Lowry supported Cr Hannan's notice of motion.
"In the case of the funding of the Wilton infrastructure projects, I see the CEO's report... in the Special Infrastructure Contributions, we've got $771 million towards the cost of delivering required infrastructure and of course, the Wollondilly Contributions Fund is up to $346 million and based on other reports that we've heard elsewhere this could be $1 billion short or even more of delivering the necessary infrastructure," he said.
"I see that we've been asking the department for these milestones, but we are not receiving that feedback yet.
"I think the reason the department hasn't given us these trigger points is that they can't. They can't fund it. They can't actually deliver it at this point. They don't know the solutions.
"It's distressing to see how under-funded this project is."
Wollondilly chief executive Ben Taylor said staff were already advocating to the department for more information about delivering core infrastructure in Wilton.
"Landcom is now the proud owner of North Wilton and... Landcom, in its presentation to council, talked about the triggers for when it would deliver the infrastructure that is required for its development," he said.
"So what council officers are doing, under council's direction, is we are advocating strongly to the department for clear trigger points on when they will deliver the infrastructure that is required for their developments, and also when the state government will provide the funding and build the infrastructure it is required to deliver under the Special Infrastructure Contribution.
"What I believe we need to see as a council is that information become public so that the community can be confident about when that infrastructure is going to be delivered."
Cr Hannan said the current and future residents of Wilton deserved clarity around the delivery of future infrastructure projects.
"Can you imagine 40,000 people living there without the infrastructure on small blocks of land?" she said.
"It won't be a nice place to be, and I don't want to have people in the future saying, 'look at what those people delivered us', I want to have a great new town out there with all the infrastructure.
"We need to know when the appropriate infrastructure will be delivered so that the people moving there can have a good quality of life."
Councillors unanimously supported the notice of motion. The council will now ask the Department of Planning to give population trigger points for delivering major infrastructure in Wilton.