Paradoxically, even when sufficient irrigation water reaches agricultural fields, it can spoil much of the land unless drained properly. Particularly in many arid areas, salts that occur naturally in the soil must be drained away with irrigation runoff. Also, poorly drained irrigation water can raise the groundwater table until it reaches the root zone, waterlogging and drowning crops. Improving irrigation efficiency. A number of countries are working to improve irrigation efficiencies, thus saving water and protecting the land.
Drip irrigation is one technique.
Drip irrigation consists of a network of porous or perforated piping, usually installed on the surface or below ground, which delivers water directly to the root zones of the crops. By 1991 this figure had grown to 1.6 million hectares. Instead, the LEPA method delivers water to the crops from drop tubes that extend from the sprinkler's arm. Irrigation options for the rural poor. Yet pressures to feed rapidly growing rural populations require making better use of scarce freshwater resources.