WDL Ground Surface Displacement - Land Subsidence Monitoring

These instruments consist of a pipe or cable anchored at the bottom of a well casing. Pipe or cable extend from the bottom of the well, through geologic layers susceptible to compaction, to the ground surface.

The pipe or cable is connected to a recorder that measures the relative distance between the bottom of the bore hole to the ground surface. These instruments are capable of detecting changes in land surface elevation to 1/100th of a foot. When land subsidence and water depth monitoring activities are paired together, hydraulic and mechanical properties of the aquifer system can be determined.