Water level in a deep well on the summit of Kilauea Volcano, Hawaii
Between March 2002 and May 2011 periodic water level measurements were made in the well on the summit of Kilauea Volcano using a 2,000-foot calibrated electric tape (Waterline Envirotech Ltd.) with graduations of 0.01 foot. Water level measurements resumed in March 2018.  
Calibration of the electric tape at the USGS …