EOS-0002 Lecture Notes - Lecture 3: Phreatic Zone, Vadose Zone, Baseflow
20 May 2016
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Document Summary
Occurance - groundwater exists in cracks and voids everywhere below the watertable - not in underground lakes and rivers. Nonstatic - water moves in the subsurface, and into/out of ground. Usage - wells pump up water, agriculture is #1 use of groundwater (90% goes to irrigation) Artesian - describes hydraulic pressure conditions of the groundwater source. Properties: porosity - n decimal % of material that is void space, permeability - k hydraulic conductivity, ease with which water passes through voids, dependent on temperature. K is more important than n in determining flow pattern. Exogenic system - powered by sunlight in the evapotranspiration phase. Water table - level below which water saturates ground, shaped as a subdued replica of land surface in humid climates. Affected by infiltration, runoff, evapotranspiration, recharge, discharge. Baseflow - discharge of groundwater into a stream or river, increased by infiltration and high permeability.
