Water Level Sensors
Solinst 105 Well Casing and Depth Indicator

The Model 105 Well Casing and Depth Indicator from Solinst is easy to use, with the ability to measure to detect metal well casing and measure total well depth without having to switch out the probe.
SITRANS LC 300 Capacitance Level Probe Transmitter

The LC300 is a 2-wire-loop-powered capacitance level probe transmitter for level measurement of liquids, solids and slurries.