Flood Risk Technology, Part III: Hydrologic and Hydraulic Modeling

This is the third article in a series about the evolution of flood risk technology. The series overview is here.

Planning and designing projects that identify risk and mitigate flooding are top of mind, especially following the devastating 2017 hurricane season and other recent dramatic rainfall events.

The foundational tools utilized by engineers and floodplain managers, who are designing those projects, are hydrologic and hydraulic (H&H) models. Initialized in the 1960s, computer models that simulate rainfall runoff and flood elevations are the basis of floodplain mapping efforts. Modeling ultimately helps us make informed decisions regarding projects that alleviate flood risk and protect natural and manmade resources from potential damage when modifications are made to creek or riverine systems.

H&H computer models have evolved significantly from the 1970s, when stacks of punch cards were run through early IBM computers to produce mapping data. Today’s detailed GIS-based, two-dimensional modeling technology is driving the stormwater industry. Modeling technology will continue to evolve and enable floodplain managers to accurately identify critical flood risk in urban areas—not based on traditional open-channel floodplains—and assess risk for areas beyond the confines of the regulatory FEMA flood zone.

The infographic below displays some of the key events that spurred the evolution of modeling and floodplain mapping.

For more information about flood risk technology or Halff’s Water Resources team, write to Info-Water@Halff.com.