Irrigation - Problems in Irrigation

Problems in Irrigation

Main article: Environmental impact of irrigation

Irrigation can lead to a number of problems:

• Competition for surface water rights.
• Overdrafting (depletion) of underground aquifers.
• Ground subsidence (e.g. New Orleans, Louisiana)
• Underirrigation or irrigation giving only just enough water for the plant (e.g. in drip line irrigation) gives poor soil salinity control which leads to increased soil salinity with consequent build up of toxic salts on soil surface in areas with high evaporation. This requires either leaching to remove these salts and a method of drainage to carry the salts away. When using drip lines, the leaching is best done regularly at certain intervals (with only a slight excess of water), so that the salt is flushed back under the plant's roots.
• Overirrigation because of poor distribution uniformity or management wastes water, chemicals, and may lead to water pollution.
• Deep drainage (from over-irrigation) may result in rising water tables which in some instances will lead to problems of irrigation salinity requiring watertable control by some form of subsurface land drainage.
• Irrigation with saline or high-sodium water may damage soil structure owing to the formation of alkaline soil
• Clogging of filters: It is mostly algae that clog filters, drip installations and nozzles. UV and ultrasonic method can be used to algae control in irrigation systems