Former Supreme Court judge David Kirby presided over an inquiry into the so-called Warringah Transport corridor in the 1980s. Credit:Ryan Stuart This was very different to the approach taken in the inquiries Mr Kirby conducted in the late 1970s and early 1980s. Mr Kirby, the self-described "somewhat shy" younger brother to the "complete show-off" Michael of High Court fame, was a 35-year-old barrister when former premier Neville Wran asked him to sit as commissioner on a road inquiry. That inquiry was to examine the so-called Kyeemagh-Chullora Road – the route of the present-day M5. Mr Kirby has described that inquiry as a turning point in his life. It led to further roles as commissioner and counsel assisting in many other inquiries.

Images from Warringah Transport Corridor Inquiry regarding Wakehurst Parkway, Parliament of NSW, 1983. And the recommendation that he made in the Kyeemagh-Chullora inquiry has had a lasting impact on the life and environment of the city. Mr Kirby recommended against building the road, partly because of the environmental devastation it would cause to part of the Wolli Creek valley. The cover of the Warringah Transport Corridor Inquiry of 1983 was a photograph by Max Dupain, which had formed the Sydney photographer's submission to the inquiry. The consequence of this recommendation was that when the M5 East was built, in the late 1990s, a tunnel was used for part of the Wolli Creek Valley and a rare pocket of green space in Sydney's inner south saved.

"I like to think, and I certainly will tell my children, that perhaps my greatest accomplishment in this lifetime was the part I played in saving the Wolli Creek Valley and the Cooks River Valley," Mr Kirby said. In the early 1980s, Mr Kirby presided over an inquiry into the so-called Warringah Transport corridor, a road reservation that ran through the Castlecrag escarpment across Middle Harbour to Seaforth. These investigations, which attracted thousands of submissions and sustained public interest, explored in detail issues that have continued to emerge as successive state governments have embarked on vast motorway projects through Sydney. One issue is whether increasing road capacity really solved the problem of congestion. The Warringah inquiry likened dealing with congestion to dealing with old age – a fact of life that can be managed, but not avoided. "Like a facelift, the provision of more road space will afford, at best, a temporary respite," Mr Kirby's report said.

On the cover of the final Warringah Inquiry report is a photograph of the Castlecrag escarpment taken by Max Dupain, a resident of Castlecrag. The photograph was Dupain's wordless yet eloquent submission to the Inquiry, which found that a road across the harbour would have diminished the "majesty" of the land-forms. However, the proposed freeway to Warringah was not simply rejected upon environmental grounds. The inquiry found that while the freeway had been proposed as a solution to congestion, it would have no significant impact upon congestion, because of the land use consequences of building a freeway. It would open up Warringah, so that it was likely that land would be re-zoned. It was common ground that another 80,000 residents could be expected, who would in turn generate traffic and the same level of congestion as before. In respect of the Premier's most recent proposal, Mr Kirby said the same land use considerations arose. "Whilst the proposal to build a tunnel is a significant improvement upon the environmentally destructive surface freeway that I was called upon to consider, the solution to the traffic woes of the Warringah peninsula is complex," Mr Kirby has written in a piece for the Herald.

"Options, including public transport options, should be identified and the public given the opportunity to express its view." Although the Premier has presented her motorway tunnel as a done deal, the length of time before any drilling is to start suggests these issues will not go away. Ms Berejiklian has not said when she would build the new tunnel, though previous government documents indicate the project could be some 10-15 years away.