Urban rainstorm and waterlogging scenario simulation based on SWMM under changing environment

Area of Science:

• Environmental Engineering
• Urban Hydrology
• Geographic Information Systems

Background:

• Increasing frequency of urban rainstorms and waterlogging leads to significant economic losses and social disruption.
• Accurate simulation of urban rainstorm and waterlogging is crucial for effective disaster prevention and mitigation strategies.

Purpose of the Study:

• To develop and apply a numerical model for simulating urban rainstorm and waterlogging.
• To investigate the influence of rainfall characteristics, pipe network implementation, and urbanization levels on waterlogging.

Main Methods:

• Utilized the Storm Water Management Model (SWMM) integrated with Geographic Information System (GIS).
• Applied the model to Lianhu district, Xi'an, China, analyzing spatial distribution, drainage capacity, and surface runoff.
• Explored the effects of varying rainfall recurrence periods, pipe diameters, and imperviousness.

Main Results:

• Increased rainfall recurrence led to higher water accumulation volumes, slower decline rates, and more waterlogging nodes.
• Pipe network optimization reduced overall overload time but could shift issues downstream.
• Lower imperviousness correlated with fewer waterlogging nodes and reduced accumulation time.
• Specific areas (west, northwest, southwest) were more sensitive to imperviousness, with limited impact from surface condition improvements alone.

Conclusions:

• The developed SWMM-GIS model effectively simulates urban waterlogging and identifies key influencing factors.
• Findings provide critical insights for urban waterlogging prevention, reduction strategies, and pipe network reconstruction planning.
• Understanding the interplay between rainfall, infrastructure, and urbanization is essential for resilient urban water management.