Remediating rather than replacing ageing infrastructure

As our population increases, so does the demand for infrastructure. However, an influx of residents, new development and increased traffic can put a significant strain on infrastructure, particularly in older suburbs surrounding large metropolitan cities such as Sydney, Melbourne and Brisbane.

Replacing ageing or damaged assets, such as underground pipes and culverts, is an expensive process that often requires ground excavation works that could take weeks or even years to complete. It can also have a significant impact on the environment and cause major disruption to roads and facilities that the community relies on.

Yet, we cannot simply leave ageing infrastructure to deteriorate. Old or abandoned stormwater, sewer, gas, water and fuel pipelines degrade over time, resulting in cracking and leaking that can cause numerous other issues such as soil destabilisation, erosion, subsidence, underground voids and ground collapse. In areas with a low water table, groundwater can build up and cause sinkholes which may damage homes and public areas.

Furthermore, as populations grow the demand on underground utility networks increases, resulting in older pipelines no longer being fit for purpose as they can’t keep up with demand. When new pipelines are then commissioned, the old pipelines are often decommissioned and left in the ground. These abandoned pipelines may need to be filled with specialty grouts to mitigate risks, such as ground subsidence, that can occur as the pipes deteriorate over time. This is especially serious if you consider the pace of ongoing development and the growing focus on new projects, such as the Queensland Government’s commitment to a $52.2 billion infrastructure pipeline[1] and $2.9 billion in local housing[2]  projects over the next four years.

What’s the answer?

For ageing infrastructure, particularly assets affected by erosion or water ingress that cannot be removed from the ground and easily replaced when they become obsolete, often the best solution is to explore remedial solutions that can future-proof and, where necessary, extend the life of the asset. An effective example of this is the work that Mainmark undertook repairing damaged steel corrugated culverts beneath an access road in Far North Queensland. Likewise, often the most fit for purpose approach is to decommission the asset outright, as was the case when Mainmark decommissioned an underground gas main at a busy intersection in Melbourne.

When remediating ageing civil infrastructure, we need to consider the following:

  • Remediation is often more cost effective. Replacing ageing pipes and drainage usually requires large local disruptions around the asset, heavy machinery, excavation works and longer timelines, leading to greater expense. Alternative solutions, such as Teretek® resin injection and Terefil® lightweight cementitious fill, provide ground strengthening and stabilisation, and can fill voids following a partial collapse. Likewise, Mainmark’s specialist waterproof resins and coatings are highly durable and provide a viable long-term solution for water and gas ingress control. These solutions often prove to be more affordable compared to asset replacement or traditional remediation methods. Advanced specialty grouts such as Mainmark’s Terefil are purpose used and superior to conventional fills for complex pipe utility abandonment. It is highly flowable, easily placed, and does not require pre-loading or compaction for settlement mitigation. It will flow into spaces to fill voids and exhibits shrinkage of less than 0.1%, making it very well suited for assets that need to be completely filled.
  • Remediation works are less invasive than alternative solutions that require excavation work and additional time to complete. Depending on the scale of the project, removing ageing or damaged pipelines often limits or completely cuts off traffic access. By using Mainmark’s innovative solutions, projects can be completed more quickly and with less disruption, including below ground infrastructure, and at sites that are difficult to access.
  • Modern remediation solutions provide superior effectiveness for utilities management. One of the biggest challenges when remediating or decommissioning old pipes is managing the flow of utilities, like water and gas, to prevent build up and leaks. Mainmark’s engineered coatings and linings are high performance control treatments that can stop flowing water or gas quickly and effectively, providing an excellent waterproofing solution to seal and stabilise water ingress.

Often infrastructure deteriorates due to a lack of investment in public works programs and failure to recognise cost effective solutions that can affect an asset’s longevity. For more information about Mainmark’s civil infrastructure remediation capabilities, or to seek advice regarding the best solution for an upcoming project, contact our customer service team on 1800 623 312 (AU) or 0800 873 835 (NZ) and they will forward your details to one of our expert team.

[1]  https://www.statedevelopment.qld.gov.au/__data/assets/pdf_file/0028/57655/queensland-government-infrastructure-pipeline.pdf

[2] https://statements.qld.gov.au/statements/93633


By Max Kudrenko – Regional Manager (Vic, Tas, SA, WA)

Max Kudrenko is the regional manager (Vic, Tas, SA, WA) for Mainmark’s civil and mining division. Max is a civil engineer who has experience working with different grout, resin and other cementitious geotechnical and ground improvement technologies in the residential, commercial, gas/oil and civil sectors. He has successfully project managed works throughout Australia, New Zealand and Japan.