Storm Surge Analysis

Exponent’s Water Resources team is experienced in performing assessments in coastal areas to evaluate the risks posed by storm surge. Storm surge is a phenomenon in which ocean water surface elevations rise as a result of high winds and decreases in atmospheric pressure during tropical storms and hurricanes. Storm surge can cause significant flooding in coastal communities. Lives and property located along the coastlines of hurricane-prone regions (e.g., the US Gulf Coast and Eastern Seaboard, islands in the eastern Pacific Ocean such as Hawaii and Guam) are at great risk during large storm events (including hurricanes) because of high water levels, which have the potential of inundating vast areas.

Storm surge may overwhelm existing flood protection infrastructure (e.g., seawalls, dikes and levees, breakwaters, groins, jetties and piers, bulkheads, sills, and perched beaches) with significant implications for coastal communities, particularly in low-lying areas.

Exponent personnel have experience in performing storm surge frequency probability analyses to determine the extent of inundation that could be expected from tropical storms and hurricanes. Various computer programs are employed to conduct a full analysis of coastal storm surge including planetary boundary layer (PBL) models, hydrodynamic models (e.g., RMA-2 and ADCIRC), the Empirical Simulation Technique (EST), and others. Estimating storm surge requires use of bathymetric and on-shore topographic data, historical tidal information, and meteorological data. Integration of LiDAR data and field inspection observations are often important in performing such studies.

Services

Exponent staff are knowledgeable in using the best available data and techniques to develop statistically-based predictions of storm surge.

Our services include:

  • Coastal flooding risk management assessments
  • Statistically-based modeling of coastal storm surge
  • FEMA flood zone mapping
  • FEMA levee certification and re-certification

Professionals

Knowledge