A rapid flood inundation model for urban flood analyses

Area of Science:

• Environmental Engineering
• Computational Hydrology
• Urban Planning

Background:

• Urban flood early warning systems require efficient inundation models.
• Conventional 2D flood models are computationally expensive.
• Alternative models like Cellular Automata (CA) and DEM-based models (DBMs) have limitations.

Purpose of the Study:

• To develop a hybrid inundation model combining CA and DBMs for efficient, high-resolution urban flood mapping.
• To integrate a 1D drainage module for reliable urban flood simulation.
• To overcome the limitations of existing CA and DBM flood models.

Main Methods:

• A hybrid model integrating CA for temporal flood distribution and DBM for flood extent details.
• Incorporation of a 1D Saint Venant equation to simulate urban drainage systems.
• Implementation of two-way coupling between 2D surface and 1D drainage models.

Main Results:

• The hybrid model efficiently produces high-resolution flood maps.
• Complex pre- and postprocessing steps are eliminated.
• Reliable simulation of urban area floods is achieved through integrated surface and subsurface flow modeling.

Conclusions:

• The proposed hybrid model offers an efficient and accurate solution for urban flood simulation.
• Integration of CA, DBM, and 1D drainage modules enhances flood early warning systems.
• This approach provides a valuable tool for urban flood risk management and mitigation.