Infiltration and runoff during the snow melting season, with forest cover

This paper presents a new method of analysis of rainfall and runoff data which permits surface runoff and ground water flow to be segregated and infiltration capacity determined during stream rise. The method is equally applicable to areas with and without snow cover. The determination of infiltration capacity during the snow melt period is, however, the most difficult problem and the method is here applied to this case, using data for areas in the Allegheny Experimental Forest, with varying degrees of forest cover density. For these areas the rate of snow melt per degree-day of temperature excess above 32 degrees F decreased as the cover density increased. During snow melt, infiltration took place at rates governed by the rate of supply of rain and melt water, averaging for the entire snow melting period one-third to one-quarter of the infiltration capacity of the soil. The infiltration capacity under snow cover with unfrozen soils was found to be about 0.05 inches per hour of 1.20 inches per day.