Flood control practices can affect 100 year flood designation
![Time line chart showing how a 100 year flood designation can change over time due to new flood controls.](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/full_width/public/thumbnails/image/wss-sw-flood-100year-flood-controls.gif?itok=xEAtgqXA)
Detailed Description
The "100-year flood" of yesterday may not be the "100-year flood" of today. Changes in local land use, new river impoundments, changes in the amount of impervious surfaces, and long-term climate patterns can affect at what point a "100-year flood" is designated.
Sources/Usage
Public Domain.