Lyu et al. (2026) Urban waterlogging hazard and sponge city mitigation in the lower Bahe River Basin, Xi'an: A complementary MIKE–HEC-RAS assessment in a semi-arid to semi-humid transitional zone

Identification

• Journal: Journal of Hydrology Regional Studies
• Year: 2026
• Date: 2026-09-15
• Authors: Jiqiang Lyu, Xiaoyu Cai, Lu Chen, Fan Lei, Wei Qian, Tianshuo Chen, Ze Zhang, Leran Qin, Pingping Luo
• DOI: 10.1016/j.ejrh.2026.103990

Research Groups

• School of Water and Environment, Chang'An University, Xi'an, China
• Key Laboratory of Underground Hydrology and Ecological Effects in Arid Areas, Ministry of Education, Xi'an, China
• College of Hydrology and Water Resources, Hohai University, Nanjing, China
• College of Biological and Environmental Engineering, Xi'an University, Xi'an, China

Short Summary

This study assesses urban waterlogging hazard and sponge city mitigation in the lower Bahe River Basin, Xi'an, using a complementary MIKE–HEC-RAS assessment. The results provide scientific support for flood-resilience planning in semi-arid to semi-humid transitional zones.

Objective

• Investigate the formation mechanisms of urban waterlogging in semi-arid cities and develop applicable modeling approaches.
• Assess inundation hazards and the benefits of mitigation measures, particularly sponge city initiatives.

Study Configuration

• Spatial Scale: The study area covers a 109 km long river reach with a drainage area of 2581 km² in Xi'an City, China.
• Temporal Scale: The analysis focuses on short-duration, high-intensity storms and design flood events with return periods ranging from 20 to 100 years.

Methodology and Data

• Models used:
  • MIKE FLOOD for simulating urban ponding and river–floodplain interactions.
  • HEC-RAS for evaluating river conveyance capacity and levee safety.
• Data sources: Topographic data, meteorological data, underlying surface data, planning document data.

Main Results

• Areas with gentle slopes, dense urban development, and extensive impervious surfaces are highly susceptible to severe waterlogging during intense rainstorms.
• Sponge city construction significantly reduces waterlogging hazards and affected areas under design flood conditions.
• Under the 20-year return-period rainfall scenario, the high-risk area was reduced by 47.56% and 72.52% in Scenarios 2 and 3, respectively.

Contributions

• This study provides a comprehensive assessment of urban waterlogging hazard and sponge city mitigation in semi-arid to semi-humid transitional zones.
• The results support flood-resilience planning and provide scientific evidence for the effectiveness of sponge city initiatives.

Funding

• National Natural Science Foundation of China (Grant No. 51979023)
• Key Research and Development Program of Shaanxi Province (Grant No. 2022SF-032)

Citation

@article{Lyu2026Urban,
  author = {Lyu, Jiqiang and Cai, Xiaoyu and Chen, Lu and Lei, Fan and Qian, Wei and Chen, Tianshuo and Zhang, Ze and Qin, Leran and Luo, Pingping},
  title = {Urban waterlogging hazard and sponge city mitigation in the lower Bahe River Basin, Xi'an: A complementary MIKE–HEC-RAS assessment in a semi-arid to semi-humid transitional zone},
  journal = {Journal of Hydrology Regional Studies},
  year = {2026},
  doi = {10.1016/j.ejrh.2026.103990},
  url = {https://doi.org/10.1016/j.ejrh.2026.103990}
}