Second-Day Feet
Water
The volume of water represented by a flow of one cubic foot per second for 24 hours; equal to 84,000 cubic feet. This is used extensively as a unit of runoff volume. Often abbreviated as SDF.
- — Service Hydrologist Reference Manual Glossary of Hydrologic Terms retrieved 2014-06-01
Weather
In hydrologic terms, the volume of water represented by a flow of one cubic foot per second for 24 hours; equal to 86,400 cubic feet. This is used extensively as a unit of runoff volume. Often abbreviated as SDF.