While New York and Hong Kong are arguably the two best known skyscraper cities in the world, Melbourne, under Liberal Planning Minister Matthew Guy, has markedly closed the gap.

The City of Melbourne, which takes in 37.7 square kilometres of land in the heart of one of the world’s most sprawling metropolises, has absorbed an average of 2000 new apartments per year over the past decade. The permissive Guy has now approved almost 100 new towers and 50,000 apartments during what has been a four-year frenzy of approvals.

State governments have long been criticised for forcing up housing prices by not releasing enough land for new stock. You can’t say that about Guy, who has approved about 25 years’ worth of supply and turned the City of Melbourne into Australia’s fastest-growing council, with population growth of 11.5% last year.

The Construction, Forestry, Mining and Energy Union is a major beneficiary of this, but it just doesn’t have the members or capacity to deliver fully on Guy’s unprecedented tower pipeline. While Guy has shut down development opportunities with restrictive new zones in the suburbs, the inner city is expected to absorb an increasing proportion of Melbourne’s annual 90,000 population growth — Melbourne is projected to surpass Sydney as Australia’s biggest city within 20 years.

As you would expect, such a scenario is triggering increasing public debate. The Age has comprehensively covered what the minister is calling  Melbourne’s biggest building boom since the gold rush, but its cross-town rivals at the Herald Sun have largely been Guy’s cheer squad. In return for their uncritical efforts, the Murdoch tabloid receives a steady stream of exclusives from the Planning Minister.

So it was a rare thing last week when Guy rejected a 300-metre skyscraper proposal from the Steve Bracks-chaired super fund Cbus at 447 Collins Street. As usual, the knock back was leaked to the Herald Sun, which on Saturday ran a political line about the Cbus’ associations with the CFMEU and Labor. The Age followed up this morning.

The Cbus refusal was particularly surprising because the proposal was endorsed by Melbourne City Council on September 9. This hasn’t happened before.

The minister has a long track record of approving towers rejected by the council, none more controversial than the $150 million David Marriner hotel tower  behind Melbourne’s historic Forum Theatre and adjacent to street art mecca Hosier Lane.

While Sydney remains constrained by its firmly applied 235-metre height limit, Melbourne has stretched its skyscraper lead with almost 20 ministerial approvals that exceed Sydney’s maximum. Indeed, the only thing stopping towers from breaking through the 400-metre mark has been federal aviation regulations protecting flight paths.

While almost 100 new towers have been approved, the only five Ministerial refusals that I’m aware of were as follows:

Guy has until 6pm on Melbourne Cup Day to make dozens more important decisions before the caretaker provisions temporarily put a stop to his enormous discretionary power.

Like everyone else, the City of Melbourne has been struggling to keep up with the scale of the decision-making. That’s why councillors asked our CEO to write this letter to the Minister summarising all the outstanding planning matters. It will be debated at the October council meeting tomorrow night.

For mine, the three most important requests are for increased developer contributions in the CBD to help the council manage record growth, transparency in the minister’s decision-making process and an end to the strange system under which the minister is responsible for all applications above 25,000 square metres. When this was introduced about 20 years ago, it applied to fewer than 10 applications a year. This year we are headed towards a record of more than 60, which is not surprising given the minister has approved more than 90% of skyscraper requests that came through his door.

Surprisingly, the Labor opposition is proposing to keep this system, which would hand the enormous discretionary planning powers to CFMEU member Brian Tee if Labor wins the November 29 election.

*Stephen Mayne is deputy chair of the City of Melbourne planning committee.