Developers will have appetite for 60,000 new high-rise dwellings along the controversial Bankstown rail line redevelopment, or nearly 25,000 more than the community has been told will be constructed, according to a previously unreported study commissioned by the state government.

The state government maintains only about 35,000 dwellings will be built in the Sydenham-Bankstown redevelopment over two decades as 11 stations such as Dulwich Hill, Campsie and Bankstown are redeveloped into a metro project. That figure has already seen it face a backlash from a slew of local residents groups.

But a report from its own consultants suggests that developers' appetite will far exceed the government's published plans for the redevelopment.

"[Modelling] suggests 58,747 new dwellings … could be financially feasible to develop," a newly released study commissioned by the department from AEC Group last year found. "[And] should the strategy be implemented new planning controls could unlock surplus market capacity of nearly 40,000 dwellings."