The escalating frequencies and changing patterns of climate change impacts, such as precipitation rates and sea levels, question the reliability of the existing engineering infrastructure, in terms of design and planning criteria for which designers and decision makers need to or account for. The objective of this paper is to assess the performance of an existing engineering infrastructure by measuring three variables: Vulnerability (β), Reliability (α), Resiliency (γ). These variables will be implemented temporally to a floodplain catchment, where performance and engineering sustainability can be depicted. The depiction will define the system's behaviour upon a natural event such as precipitation or sea-level rise. Nevertheless, Flood Risk Index (FRI), which depends on (β, α and γ), will be applied as an overall index to demonstrate the trend context as well as give implications of the sensitivity significance of β, α and γ. The main outcome of this paper is to depict the relative sustainability or as known as the performance assessment indicators temporally; and to examine the correlation between the indicators on a real-flow data. These procedures shall ultimately provide implications on the implementation of the indicators to achieve a relatively sustainable system.

Climate change impacts on engineering infrastructures are increasing. The infrastructures are expected to withstand more frequent and severe weather events, more climate variability, and changes in climate norms (average conditions). It is anticipated that many civil infrastructure systems such as storm drainage, will fail to meet the expected environmental pressures. Therefore, it is important to identify current and future risks; to develop strategies for adapting such risks; and to implement an effective maintenance plan. In the study, the climate change impacts on storm drainage were investigated, particularly in Southport, Queensland, Australia. The historical rainfall data for 120 years were analysed to identify the changes in the trends, patterns and frequencies of rainfall. The peak flow in a flooding event was identified. The investigation provides essential information for the vulnerability to risk failure of the existing storm drainage system, such as at a critical pipe failure point. Finally, the research applied a risk-based vulnerability assessment by risk analysis and management quantification tools to quantify the impact that rainfall may induce through storm drainage failure.

This study develops a flood risk assessment method using a temporal analysis of hydraulic data of a floodplain catchment in extreme weather event. The research includes two phases. In Phase 1: a 2-dimensional hydraulic model in the lower Nerang River on the Gold Coast, Australia is established, which provides accurate estimations of the water level and flow. Then, in Phase 2, a risk assessment model is developed to evaluate the risk due to the floods. The risk model consists of four indices: Vulnerability (β), Reliability (α), Resiliency (γ) and Flood Risk Index (FRI). These indices have the capability of representing the hydraulic system's behaviour from the risk incurred. Ultimately, the risk assessment will enhance the decision making process to achieve a sustainable and more resilient infrastructure, as well as give implications on the optimization of engineering planning and design.