Out with the old, in with the new? Asset owners are rethinking how they manage ageing pipe networks as emerging ‘condition assessment technologies’ expose the cost and risk of relying solely on theoretical asset lifespans (which has been the go-to for years). Supplied by the Integrated Pipeline Solutions (IPS) Alliance.
Traditionally, pipe renewals have followed standard age-based assumptions, with utilities replacing sections based on estimated design life rather than verified condition. But, evidence is mounting that this approach is often wasteful and potentially harmful.
“Utilities have dug up pipelines expecting to find deterioration, only to discover the pipe is still structurally sound or they have not been dug up soon enough, resulting in failure,” says Christopher Miller, Business Development Manager for the Assetlife Alliance, a member of the IPS Alliance.
“That’s money left on the table for good assets and a lost opportunity to reallocate resources to assets that genuinely need attention before they fail prematurely.”
At the same time, unplanned maintenance caused by failures in high-criticality mains, especially those running through urban corridors, can cause significant disruption, commercial losses, reputational damage and, in the case of wastewater assets, serious cultural and environmental consequences.
From reactive to evidence-based
Emerging non-destructive testing (NDT) tools are shifting the focus from reactive to evidence-based maintenance.
Technologies like induced pressure transient, ultrasonic testing and magnetic flux analysis can assess the wall thickness and detect corrosion in metallic pipes to provide reliable data on asset condition without service interruption and at significantly reduced material costs.
These methods are already widely used in industries such as oil and gas but are only now gaining traction in the water sector.
“The water industry has lagged behind in adopting NDT, often because of legacy approaches or limited access to the right expertise,” says Miller. “But the shift is underway.”
One approach now gaining broader use is under-pressure tapping (UPT). Commonly used to install live connections, UPT is now being used to extract physical samples, known as ‘coupons’, from pressurised pipelines for lab analysis.
It’s a way to gain critical insights into pipe integrity, chemical composition and remaining service life without shutdowns, and when combined with other technologies it gives higher confidence in future asset life.
Recent UPT projects for major councils on wastewater rising mains showed how data gathered through live sampling can inform targeted renewals. For example, samples revealed differences in wall thickness, levels of corrosive damage and wastewater aggressivity – information that would otherwise remain unknown.
The scale of the challenge
Our country’s water, wastewater and stormwater assets vary widely in age and material. Some pipelines are more than 100 years old and others are less than a decade old. The condition of each depends on a complex set of factors, including installation practices, usage and surrounding environment.
For infrastructure owners, this variability makes it difficult to predict failure or schedule replacements accurately. The result is often a mix of over-investment, replacing assets prematurely and under-preparedness; where failure occurs without warning.
“In the past, the sector has operated with low confidence in the actual state of buried assets,” says Miller. “That leads to either overspending or playing catch-up when something breaks.”
Collaborative delivery makes technology accessible
While the technologies themselves are becoming more available, the skills to deploy them are still specialised. For smaller utilities or regional councils, accessing the right tools, teams and analytical capabilities can be a barrier.
That’s where collaborative models like the IPS Alliance have emerged. Formed by four New Zealand-based firms – ProjectMax, Intergroup, Assetlife, and Pipeline & Civil – IPS provides a single point of contact for clients needing condition assessment, maintenance and remediation services. The alliance structure allows scalable delivery, drawing on a broad pool of expertise and equipment.
“Bringing multiple specialists under one roof reduces complexity for the client,” says Miller. “It’s less about selling a service and more about reducing friction in how critical work gets done.”
The model also helps accelerate the adoption of new technologies by embedding them within familiar delivery structures.
From firefighting to foresight
Miller says better data leads to better decisions. With detailed condition assessments, asset managers can move beyond age-based triggers and develop more accurate maintenance plans. This shift improves budget predictability, reduces emergency works, and increases the lifespan of viable assets.
It also helps avoid the broader costs of failure; disruption to traffic and commerce, environmental damage from wastewater overflows, and public backlash over service outages.
“Infrastructure failures make headlines, but proactive maintenance doesn’t,” says Miller. “That’s why we need to keep educating both the sector and the public about the value of investing in invisible assets.”
This approach is advocated for in the recently published Water NZ Pressure Pipe Inspection Manual, authored by IPS Alliance member ProjectMax.
The manual outlines the importance of planning inspections and interventions such that the right approach in the right location takes due regard to both asset criticality and cost. The manual also introduces the concept of data confidence and how this should be used to justify (or not) additional investigations.
Looking ahead
As pressure grows to improve infrastructure resilience while keeping costs down, evidence-based approaches will become essential.
We are not alone; globally, municipalities face similar challenges of ageing infrastructure, limited budgets, and political pressure to do more with less.
While technology can’t solve every problem, it can eliminate much of the uncertainty. Live data from non-destructive assessments allows utilities to allocate capital where it’s needed most—and avoid spending it where it isn’t.
“Ultimately, it’s about confidence,” says Miller. “Confidence in the data, in the decisions, and in the delivery. The tools are here. The challenge now is uptake.”