A pure polyurea coating was applied to the internal surfaces of a 4.55 megalitre drinking water reservoir in Far North Queensland, where active leaks had been detected.
SPECIAL REPORT
Why paying attention to specialised resins and coatings is vital for protecting Australia’s water infrastructure by Matt McLean, Operations Manager, Specialised Resins & Coatings, Mainmark Water supply systems such as dams, tanks and sewage treatment plants provide essential services for Australian communities. And while these marvels of engineering undertake important functions, we must also acknowledge that their quality and longevity play a vital role in maintaining the comforts of modern society. It is why specialised resins, gels and coatings for asset preservation can be just as important – if not more – as the water infrastructure they serve. Waterproofing products come in many forms including acrylic based hydrostructural resin, chemical injections and cementitious grouting options. These products are designed to bear high pressure levels and prevent water from causing infrastructure damage that is 46
Waste + Water Management Australia | Jan 2021
often too slow and gradual to notice until costly repairs are needed. Resins, gels and coatings designed to keep water at bay must also be versatile and resistant to properties other than H2O. For example, water stopping measures utilised for sewage treatment plants and water recycling tanks must contain anti-corrosive properties to withstand the various chemicals associated with these types of infrastructure.
What can go wrong? The ramifications of taking infrastructure protection for granted No matter how big or structurally solid an infrastructure asset may seem at first, water, chemicals and geological profiles are capable of causing serious structural issues or degradation over time. The
effects are costly and often require repairs that affect an untold number of assets. Large pipes and underground tanks, for example, can be subject to water ingress which can cause ground movement and cracking. The resulting effects can create water permeation that weakens the ground around the structure, accelerating structural degradation. Chemicals commonly used in water treatment and sewerage plants can quickly degrade concrete linings. Chemicals start eating away at the concrete fines which in turn speeds up the ageing process. Even infrastructure with reinforced steel is not immune. Without proper protection, the presence of water allows carbon dioxide to enter the concrete and cause a chemical reaction that affects water quality and infrastructure integrity. This is known as ‘concrete cancer’.