Infiltration Index : An average rate of infiltration, in inches per hour, equal to the average rate of rainfall such as that the volume of rainfall at greater rates equals the total direct runoff
National Weather Service NWS Forecast Office, National Oceanic and Atmospheric Administration NOAA, SH Manual, Glossary of Hydrologic Terms, Washington, DC, USA 2015. http://www.nws.noaa.gov/om/hod/SHManual/SHMan014_g lossary.htm, (HydroI - Amer) {889}