Groundwater Discharge along the Southern California Coast - Geophysical Images of Three States of Salt Water Intrusion

Abstract

The interface between fresh groundwater and saline water in coastal areas is frequently complex. The natural discharge of groundwater to the near shore zone is controlled by multiple factors including the permeability of the aquifer system, faults, confining units, and the hydraulic gradient in the aquifer. The natural balance is often disturbed by heavy pumping that can cause significant intrusion of salt water into the on-shore portion of the aquifer. The shape of the salt water wedge is affected by the pattern of pumping, the properties of the aquifer, and hydraulic boundaries like faults and confining units.