Infiltration. Rainwater that soaks into the ground and may reach the groundwater table. Base flow: Where Groundwater Meets Surface Water. Base flow is the portion of stream flow that comes from subsurface flow: water infiltrated but returned to the surface in a stream channel.
Rainwater that soaks into the ground and may reach the groundwater table.
24 inch double ring infiltrometer with Mariotte Tubes http://www.hilbec.com/STORMWATER.htm
Infiltration starts at a constant rate, f0, and is decreasing exponentially with time, t. After some time when the soil saturation level reaches a critical value, the rate of infiltration will level off to the rate fc.
In a few minutes we will do an example using Horton’s Equationusing an average rectangle estimate to the area under the curve.
Estimates Equation 2: F index
Infiltration Volume = total rainfall volume – runoff volume as measured in the rain gages and at the outlet gage, respectively.
F assumes infiltration volume resulted from a constant infiltration rate. It assumes a high initial infiltration is balanced by a low later infiltration.
Example: Guessing EquationF
We will find F in this problem by guessing a value for F , calculating the total runoff that would result, and comparing our answer to the known runoff.