How well did floodplain mapping explain what Harvey actually did?

Floodplain Stress Test

Harvey did not make floodplain maps useless. It made their limits visible. This page compares mapped floodplain context with field evidence collected after the storm.

Cell color is a low/moderate/high stress class from the maximum observed USGS high-water-mark height above ground among records in that cell. It is not continuous flood depth, inundation extent, or parcel risk; empty or low cells do not mean no flooding.

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