Groundwater wells, potentiometric surface, and flow direction can be mapped in a KML file with the KML_3Point-Flow.v?.xlsm workbook (Figure 1). Potentiometric surface is simulated by fitting a planar surface to groundwater levels from between 3 and 24 wells. Appropriateness of fitting a 3-point problem to greater than three wells can be evaluated with a scatter plot of measured and simulated water levels. Posting of names, measured water levels, simulated water levels, residuals, and weights are specified by the user.
Groundwater-flow direction is depicted with a three-dimensional arrow that can be scaled by the user (Figure 2). Groundwater gradient and downgradient compass heading are reported if arrow is selected in Google Earth.
KML_3Point-Flow.v3.xlsm and explanatory PDF can be downloaded with the following link.
Revisions
March 8, 2021—Versions 1 and 2 were created during development.
December 7, 2021—Revisions in version 3 include the following. Workbook modified so that well locations can be specified with decimal latitude-longitude or UTM coordinates. Explanatory comments were added to labels on XYZ page.
February 23, 2024—Revisions in version 4 include the following. Safeguards were added to check that the Solver is installed and the workbook is not opened from within a zip file.