Surveying 4 Water offers two survey methods to identify potential groundwater-bearing zones in which to construct a well. The Very Low Frequency (VLF) method and a magnetometer instrument for measuring the earths magnetic field.

VLF METHOD
The VLF method can detect conductive or resistive zones at depths up to 300 meters. There are VLF transmitters around the world operated by the U.S. Government for communication and geological analysis in the 5 to 30 kilohertz range. The VLF instrument measures the strength of a VLF signal, called the primary field, and compares it to the strength of a secondary field induced by the primary field in conductive bodies at depth. With this method we are able to see the geological structures beneath the surface by their differences in conductivity. The longer the transect, the deeper conductivity contrasts can be seen. In areas of hard rock, only the fractures in the rock may yield enough water for a well. The contrast between the low conductivity of the hard rock and the high conductivity of the groundwater in a fracture allows the fracture to be detected. In sedimentary rock, the contrast will be between the low conductivity of clay and the high conductivity of saturated sand and gravel strata. Despite the good success rate of this method, Surveying 4 Water cannot guarantee water will be found in the recommended target zones. Mineralized zones are also good conductors and these zones may not contain groundwater. A typical conductivity profile is shown below. Blue represents non-conductive zones and red represents very conductive zones. Drilling targets are selected by conductivity and breadth.