Water-Level Change Map Between Two Gauging Dates
One file with more than one gauging date in it is all this needs. Pick the two events, and the difference between the two surfaces is contoured: rises one way, falls the other, and the wells that were not gauged on both dates are named rather than silently dropped out of the arithmetic.
Drop a CSV or an Excel file of your wells here
One row per well, with coordinates and whatever you want mapped. It is read in this tab and never uploaded.
A made-up site: Kestrel Lane Terminal does not exist. Fourteen wells gauged 2026-03-14 and thirteen of them again 2026-06-12, on a local grid in metres. The file carries a top-of-casing elevation and a depth to water rather than a groundwater elevation; that column is computed here, in both rounds, before the two are differenced.
Or paste the rows
Copy a block straight out of a spreadsheet — tabs, commas and semicolons all work, and you do not have to tell us which. A workbook you dropped appears here as text; editing it re-reads it as text.