Risk assessment of seawater intrusion in the Red River Delta of Vietnam

The Red River Delta (RRD) in Vietnam is highly vulnerable to seawater intrusion, on which the disaster risk assessment is essential for effective regional disaster prevention and mitigation. We developed a comprehensive indicator system for assessing seawater intrusion risks by analyzing the disaster risks and their spatial distribution across the provinces of Hai Phong, Thai Binh, Nam Dinh, and Ninh Binh. Results show that: ① The disaster risk levels range from 0.35 to 0.67, reflecting a low to moderate risk level, with a decreasing trend from the southeastern coastal regions to the northwestern inland areas; ② The risk indicators range from 0.22 to 0.53, indicating low to moderate level, with high-risk areas concentrated along the coasts of Nam Dinh, Hai Phong, and Thai Binh; ③ The exposure indicators span from 0.20 to 0.87, showing moderate to high level of exposure, with elevated levels in the eastern coastal regions of Nam Dinh and Ninh Binh; ④ The vulnerability indicators range from 0.50 to 0.79, indicating moderate to high vulnerability, with the highest vulnerability observed in Ninn Binh; ⑤ The risk of seawater intrusion disasters is mainly affected by the exposure and vulnerability of regional socio-economic systems., to which we shall consider the need for region-specific disaster prevention and mitigation measures. This study provided a critical insight for enhancing disaster resilience against seawater intrusion in the RRD.