Irrigation management system

A method for monitoring replenishment of groundwater on an irrigated farm or group of farms or another land area subject to groundwater depletion, comprising:

• installing moisture sensor devices below grade at a plurality of locations on a farm or group of farms, with sensor probes at a series of subsurface depths including below root levels of any vegetation,
• the moisture sensor devices having wireless data transmission capability for transmission of moisture content data signals over a distance, and
• at a monitoring location remote from the farm or land area, monitoring soil moisture content at a series of depths and at plural locations on the farm or farms or other land area using data as transmitted by the moisture sensor devices, so that replenishment of groundwater at the farm or farms can be determined by moistening of subsurface soils, including below roots, indicating migration of water down to a water table,
• thereby providing information useful in balancing water use, including groundwater use, against an estimated replenishment of groundwater by water seepage through subsurface soil down to the water table.