Cardenas-Caro et al. (2026) Assessing multi-flood hazard zones for stormwater infrastructure in highly urbanized coastal cities

Identification

• Journal: Journal of Hydrology
• Year: 2026
• Date: 2026-10-10
• Authors: L.T. Cardenas-Caro, Felix Luis Santiago-Collazo, Orlando M. Viloria-Marimón, J.B. Robider, E.R. Gavin, Logan Bayer, Matthew V. Bilskie
• DOI: 10.1016/j.jhydrol.2026.136597

Research Groups

• School of Environmental, Civil, Agricultural, and Mechanical Engineering, University of Georgia, Athens, GA, United States
• Institute for Resilient Infrastructure Systems, University of Georgia, Athens, GA, United States
• River Basin Center, University of Georgia, Athens, GA, United States

Short Summary

This study investigates subsurface compound flood hazard zones (FHZs) within stormwater drainage systems using the Storm Water Management Model (SWMM). The research evaluates the influence of tides, rainfall, and future sea-level-rise scenarios on FHZ behavior in two urban watersheds in Savannah, Georgia.

Objective

• Investigate how coastal, transition, and hydrologic flood hazard zones can be objectively identified within stormwater drainage networks using conduit water-level responses.
• Evaluate how tidal forcing, rainfall, and future sea-level-rise alter the spatial extent and evolution of compound FHZs within stormwater drainage networks.

Study Configuration

• Spatial Scale: Two urban watersheds in Savannah, Georgia (Fells Street and Casey North).
• Temporal Scale: 2050 sea-level-rise scenario with intermediate projection of 0.36 m.

Methodology and Data

• Models used: Storm Water Management Model (SWMM) for one-dimensional dynamic rainfall-runoff simulations.
• Data sources: NOAA Atlas 14 intensity-duration-frequency curves, USGS Continental US Land Cover Projections model, USGS 3DEP dataset, and Savannah Area Geographic Information System (SAGIS).

Main Results

• Subsurface transition FHZs develop within confined stormwater systems and are highly sensitive to threshold selection, network configuration, and downstream tidal forcing.
• The coastal FHZ in the Fells Street watershed shortened by approximately 80% under sea-level-rise relative to the 10% no-sea-level-rise scenario.
• Simple linear superposition of isolated rainfall and tidal responses may produce physically unrealistic water levels in confined drainage systems.

Contributions

• This study extends the flood hazard zone framework to subsurface stormwater systems, providing a process-based interpretation of compound flooding.
• The proposed conduit-depth-relative framework complements conventional drainage performance metrics by identifying where hydraulic behavior is primarily controlled by coastal forcing, rainfall-runoff processes, or their interaction.

Funding

• Not specified in the provided text.

Citation

@article{CardenasCaro2026Assessing,
  author = {Cardenas-Caro, L.T. and Santiago-Collazo, Felix Luis and Viloria-Marimón, Orlando M. and Robider, J.B. and Gavin, E.R. and Bayer, Logan and Bilskie, Matthew V.},
  title = {Assessing multi-flood hazard zones for stormwater infrastructure in highly urbanized coastal cities},
  journal = {Journal of Hydrology},
  year = {2026},
  doi = {10.1016/j.jhydrol.2026.136597},
  url = {https://doi.org/10.1016/j.jhydrol.2026.136597}
}