HEC vs. HEC


H&H trivia question: Does the “H” in HEC stand for hydrological or hydraulic?


H&H trivia answer: Well, the answer depends whether you’re dealing with the U.S. Army Corps of Engineers or the U.S. Department of Transportation Federal Highway Administration. To the Corps of Engineers Hydrologic Engineering Center, the “H” stands for Hydrologic, but to the Department of Transportation that publishes Hydraulic Engineering Circulars, it stands for Hydraulic. If you want to avoid confusing them, just remember that the FHA publications always use two digits (HEC-05 is FHA whereas HEC-5 is USACE).

For reference, here’s a list of the HEC programs and publications of which I’m aware. If I’ve missed some, please let me know.

U.S. Army Corps of Engineers Hydrologic Engineering Center Software:

  • HEC-1 Flood Hydrograph Package => HEC-HMS
  • HEC-2 Water Surface Profiles Program => HEC-RAS
  • HEC-3 Reservoir Analysis for Conservation
  • HEC-4 Stochastic Streamflow Generation Program
  • HEC-5 Simulation of Flood Control and Conservation Systems
  • HEC-6 Scour and Deposition in Rivers and Reservoirs

Federal Highway Administration Hydraulic Engineering Circulars:

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