Digitalised Hammer for Gravity Sewer Condition Assessments

The hammer tapping method is widely used by Sydney Water and other major water utilities to assess the condition of concrete sewer pipes.

In this method, an inspector taps the concrete surface with a hammer and interprets the sound produced to judge whether the concrete is sound or deteriorated and in need of repair. While this method is simple and cost-effective, it is inherently subjective, qualitative, and difficult to repeat, resulting in imprecise data for condition assessments. To improve accuracy and better predict pipe performance, a quantitative, repeatable, and objective measurement approach is needed.

Led by researchers at The University of Sydney, this project will develop a digitalised hammer—a smart, sensor-equipped tool for assessing the condition of concrete sewer pipes. The tool will be validated through laboratory and field trials and designed for straightforward adoption by existing inspection crews. By enabling objective condition assessments, this innovation will support risk-based maintenance decisions, reduce unnecessary repairs, and potentially save hundreds of millions of dollars in long-term infrastructure costs for Sydney Water and other Australian water utilities.