04/08/2026
Sarah Trotman, ONZM:
Is our Infrastructure Ready for Intensification?
The large sinkhole that recently opened on Hackett Street in St Mary's Bay is more than a local curiosity. It is a serious warning.
As Auckland continues to debate Plan Change 120 (PC120) and the future shape of our city, the image of another road collapsing beneath our feet, in another of our oldest suburbs, is a powerful reminder that infrastructure is not an optional extra. It is the foundation upon which any successful intensification is built.
The St Mary’s Bay sinkhole joins a growing list of failures across our unique character suburbs. Ageing wastewater pipes, overloaded stormwater systems and deteriorating underground infrastructure have become increasingly visible. These failures are no longer theoretical risks discussed in engineering reports. They are appearing in our streets, the ones Council wants to intensify with 6-15 story apartments.
New developments are rightly required to demonstrate adequate wastewater, stormwater and drinking water capacity. Those requirements exist because infrastructure matters. Yet residents in our first suburbs rightly questioned whether the existing network is genuinely capable of accommodating the scale of intensification proposed under PC120.
That concern is not simply emotional or political. It is increasingly a legal one.
Legal commentary by Wynyard Wood asks the important question: "Does Inadequate Infrastructure Make PC120 Vulnerable to Legal Challenge?" Their conclusion is straightforward: councils cannot responsibly plan for substantially more residents without properly considering whether the infrastructure required to support that growth exists. They argue that infrastructure capacity is a "legally relevant factor" and that failing to properly assess it may expose planning decisions to judicial review and other legal challenges.
That legal analysis raises an issue that deserves serious attention. Planning cannot simply be about building heights and zoning maps. Pipes, drains, water supply, transport and public services are equally fundamental.
The recent reduction in character protections adds another dimension to the concerns of most Waitemata Local Board area PC 120 submitters. It’s proposed that protected character homes reduce from 21,000 to 15,400. For many residents, this represents more than the loss of important character protections. It reflects a planning process that appears increasingly willing to trade neighbourhood character for housing capacity without first providing confidence that the underlying infrastructure can cope.
This concern has united residents across Auckland's historic suburbs.
Residents’ Associations from St Mary's Bay, Freemans Bay, Herne Bay, Parnell and elsewhere have collectively devoted thousands of volunteer hours and significant sums in expert planning, engineering and legal advice preparing submissions on PC120. Much of that effort has not been about opposing housing itself. Rather, it has questioned if Auckland’s older suburbs have adequate infrastructure that can sustain relentless intensification.
The experience of St Mary's Bay illustrates why these concerns persist.
Following earlier storm events and infrastructure failures, residents have repeatedly highlighted deficiencies in drainage and stormwater systems. More recently the Parnell and now St Mary’s Bay sinkholes reinforce public concern that parts of our underground network may well be approaching the limits of their service life.
St Mary's Bay resident John Hill recently described the latest collapse as evidence that these issues have been visible for some time rather than appearing without warning. His comments reflect the frustration many local residents feel; that infrastructure problems are often managed only after visible failures occur rather than through proactive renewal.
Good planning requires sequencing.
Cities throughout the world intensify successfully when infrastructure investment leads growth, not when it struggles to catch up afterwards. Reliable drinking water, resilient wastewater systems and effective stormwater networks are the essential enablers of sustainable housing.
Infrastructure may not generate the same headlines as apartment buildings or zoning changes, but when it fails, the consequences are serious.
Auckland deserves an approach that balances growth with resilience. It deserves planning that is evidence-based, transparent and capable of earning public confidence. Most importantly, it deserves a council that sees community engagement as more than a statutory obligation.
The people who have invested countless volunteer hours preparing submissions, commissioning expert reports and participating in hearings are not obstacles to progress. They are citizens seeking to improve the city they call home.
As PC120 continues through its process, Auckland Council has an opportunity to rebuild trust as well as infrastructure.
That begins by listening to communities in a more authentic way, not simply hearing submissions, but genuinely engaging with the concerns they raise. When residents repeatedly point to ageing pipes, overloaded drainage systems and visible infrastructure failures, those warnings deserve more than acknowledgement.
The sinkhole in Hackett Street is a hole in the road. Adequate infrastructure should not become a hole in our planning.
To contact Sarah Trotman, in her capacity as a C&R Member, email her at [email protected]. To contact her, in her capacity as an Elected Member of Auckland Council’s Waitematā Local Board, email her at [email protected] or you can give her a call on 021 487 583.
#
