Sustainable Concrete for Wastewater Infrastructure

Sydney’s water infrastructure needs to be more durable if it is to continue to provide essential services such as water, wastewater, recycled water, and stormwater management.

The traditional concrete used to build and maintain this infrastructure is no longer sustainable—both because of its large carbon footprint and because it is susceptible to various types of corrosion, particularly microbial-induced. Sydney needs water infrastructure that can better withstand the harsh environmental conditions of pipes and waterways to reduce maintenance and the huge costs associated with repairs and rebuilds.

This project will develop technical recommendations for Sydney Water to consider when updating its internal concrete specifications. The recommendations will propose a shift from prescriptive to performance-based requirements to help Sydney Water reduce corrosion risk, improve asset durability and make use of innovative, low-carbon concrete materials as they emerge on the market.

The project will involve reviewing alternatives to traditional concrete materials—including supplementary cementitious materials and alkali-activated binders—against 100-year design life criteria and Sydney Water’s regulatory and sustainability requirements. The project will also deliver a Low Carbon Concrete Mix Selection Tool which sets carbon limits for different grades of concrete. In these ways, the project will help Sydney Water build and maintain long-lasting water infrastructure and lead the way for other national water utilities to follow.