Understanding the collapse: forensic engineering investigation of Lake Tempe artificial island failure

The authors conducted a comprehensive investigation of the failure of artificial islands designated for disposal areas as part of the Lake Tempe revitalisation project in Indonesia. This investigation integrates hydrological, hydraulic, geotechnical, and construction methodologies to identify the underlying causes of failure and propose effective mitigation strategies. The analysis revealed that, while the design of the islands satisfied technical requirements, the failure during construction in 2019 was primarily attributed to floodwater levels exceeding the design elevation for a 20-year return period, leading to water overtopping and subsequent collapse. Mitigation measures, including barrier construction and continuous monitoring of water levels, were implemented by the contractor to prevent and minimise failures during construction. The key conclusions include the adequacy of the design specifications in accommodating the maximum floodwater levels and waves, as well as the stability of the island slopes. This study underscores the importance of continuous monitoring and adaptive mitigation strategies to mitigate the risks associated with natural hazards and construction challenges. This study provides valuable insights into the design and construction of artificial islands, particularly in regions prone to flooding. This emphasises the necessity of proactive measures and adaptive strategies to ensure the resilience and sustainability of artificial island infrastructures.