Integrated hydrodynamic and machine learning models for compound flooding prediction in a data-scarce estuarine delta

Abstract

Abstract. Flood forecasting based on water level modeling is an essential non-structural measure against compound flooding over the globe. With its vulnerability increased under climate change, every coastal area became urgently needs a water level model for better flood risk management. Unfortunately, for local water management agencies in developing countries building such a model is challenging due to the limited computational resources and the scarcity of observational data. Here, we attempt to solve the issue by proposing an integrated hydrodynamic and machine learning approach to predict compound flooding in those areas. As a case study, this integrated approach is implemented in Pontianak, the densest coastal urban area over the Kapuas River delta, Indonesia. Firstly, we built a hydrodynamic model to simulate several compound flooding scenarios, and the outputs are then used to train the machine learning model. To obtain a robust machine learning model, we consider three machine learning algorithms, i.e., Random Forest, Multi Linear Regression, and Support Vector Machine. The results show that this integrated scheme is successfully working. The Random Forest performs as the most accurate algorithm to predict flooding hazards in the study area, with RMSE = 0.11 m compared to SVM (RMSE = 0.18 m) and MLR (RMSE = 0.19 m). The machine-learning model with the RF algorithm can predict ten out of seventeen compound flooding events during the testing phase. Therefore, the random forest is proposed as the most appropriate algorithm to build a reliable ML model capable of assessing the compound flood hazards in the area of interest.

Tidal Flood Model Projection Using Land Subsidence Parameter in Pontianak, Indonesia

“…Pontianak is one of the cities in West Kalimantan Province, Indonesia which is often affected by tidal floods, especially in the riverbank areas (BPIW, 2017;Gultom et al, 2020). Previous studies (Kuntinah et al, 2021;Sampurno et al, 2022a;Sampurno et al, 2022b) have shown that tidal flood in Pontianak often occurs during the high tide seasons from December to February. During this period, the tides reach a maximum height because affected by Asian monsoon (Kästner et al, 2018).…”