Rethinking Dilapidation Surveys with High-Resolution Aerial Data and the DMC-4 Sensor
August 6, 2025 Rethinking Dilapidation Surveys with High-Resolution Aerial Data and the DMC-4 Sensor Large-scale infrastructure projects like Melbourne’s North East Link, Sydney’s Metro West, or Perth’s Byford Rail Extension are reshaping our urban landscapes and transportation networks. While these developments promise improved connectivity and reduced congestion, they also present significant challenges in monitoring and documenting the condition of surrounding structures and assets. Dilapidation surveys play a crucial role in these large-scale projects by providing a detailed record of the existing condition of nearby structures and infrastructure before construction begins. This documentation helps protect all parties involved, from contractors, developers, and property owners. By establishing a baseline that can be referenced to if damage claims arise during or after construction, these surveys enable all parties to proceed knowing they are protected. However, traditional large-scale dilapidation survey methods can often be time-consuming and can disrupt both project timelines and local communities. Large scale infrastructure projects, such as highways, railways, and urban developments present significant challenges when it comes to monitoring and documenting the condition of surrounding structures and assets. Consider the North East Link project in Melbourne – a massive infrastructure project that requires digging 6.5 kilometres of tunnel under thousands of houses, businesses, parks and roads. Traditional dilapidation survey methods often involve manual inspections with boots on the ground or in a vehicle, which can be time consuming and disrupt the project and local communities. As a result, there’s a growing need for more advanced methods to ensure comprehensive and timely assessments. To explore how aerial technology could address these challenges, we put our capabilities to the test. In a recent test flight, our team explored the capabilities of our Leica DMC-4 sensor – the only sensor of its kind in Australia – at an altitude of 2,400 feet above the ground allowing us to capture data at a 2cm Ground Sample Distance. This endeavour was particularly challenging due to the sensor installation in a pressurised, twin-turbine aircraft, which is not ideally suited for the low-speed requirements of high-resolution imaging. To mitigate this, we flew into strong headwinds to reduce the aircraft’s ground speed to approximately 90 knots, allowing the sensor to capture the necessary detailed, high-quality images. Processing this high-resolution imagery requires an equally detailed and accurate surface model, which is achievable through existing imagery or LiDAR sources. While our current workflows are not tailored for this, the successful test indicates the feasibility of adapting our processes to accommodate such data. This experiment demonstrates the potential for high-resolution aerial imagery to revolutionise dilapidation surveys, offering a more efficient and comprehensive approach to assessing large areas, quickly and efficiently. Our recent test flight with the Leica DMC-4 sensor demonstrates the potential of high-resolution aerial imagery in revolutionising dilapidation surveys. By capturing detailed data at a 2 cm Ground Sample Distance, we can assess large areas more efficiently and with greater accuracy and detail. While challenges remain – such as adapting workflows and equipment – the benefits of integrating advanced aerial surveying techniques into large-scale dilapidation surveys are clear. Embracing these innovations will not only enhance the quality of infrastructure assessments but also minimise disruptions to communities, paving the way for smarter, more sustainable development.