Pumping and Runoff
The graphs above are based upon data collected by DWP and ICWD, and released by ICWD.
During the "control" period of no pumping, the water table in well 23T is graphed as above the ground surface because the well was flowing (i.e. it was an artesian well). The height above ground surface was calculated by measuring the hydrostatic pressure of the water flowing from the well and converting the pressure to feet, just as a barometer reading is a conversion of atmospheric pressure into inches of mercury.
In the control period, changes in the water surface elevation are small and are not correlated with runoff. In both periods of pumping, water surface elevation is correlated with valleywide runoff and to a much greater degree with valleywide pumping.