soil-water zone (unsaturated zone, vadose zone) The zone between the ground surface and the water-table. Water is able to pass through this zone to reach the water-table, but while in the zone it is not given up readily to wells because it is held by soil or rock particles and capillary forces. See GROUNDWATER.

soil-water zone(unsaturated zone, vadose zone) The zone between the ground surface and the water-table. Water is able to pass through this zone to reach the water-table, but while in the zone it is not given up readily to wells because it is held by soil or rock particles and capillary forces. See groundwater.