What is Irrigation?
Irrigation is the process by which water is brought to land through any of a variety of artificial means. The land that is being irrigated usually contains crops, grass or vegetation that would not usually receive enough water from rainfall or other natural sources. Sometimes the reason to irrigate a portion of land is that it happens to be a dry season with less than average amounts of rainfall, while other times it is necessary to do so because that land never would receive enough water on its own to be fertile. The water that is used for irrigation may be taken from nearby lakes, reservoirs, rivers or wells.
The amount of water that is to be used for irrigation is dependent on the type of crop that is being farmed as well as the amount of rainfall associated with the climate of the region where the farm is located. There are some countries in the world where water is used for irrigation more than it is used for other purposes. In the United States, about a third of the total amount of water that is used each year is utilized for the purpose of irrigation.
Water that is brought to a farm from a source of surface water such as a lake or reservoir is usually done so through a series of canals. When the source is ground water from a well, the water is pumped to the surface and transported to the farm via a network of pipes. In both cases, there are several ways that water can be lost in the process of irrigating the land, including evaporation, leakage, and transpiration, which is the loss of water that has been absorbed by nearby plants and weeds. There can also be algae blooms in surface water, which can cause the water to become unsuitable for irrigation.
There are several methods used for irrigating farmland, and each one needs an experienced farmer to know exactly how much water to use and when to use it. One of these is surface irrigation, where the farmer disperses water over the land by either flooding it or running it down lanes in the field called furrows. Another method is sprinkler irrigation, where water is run through pipes over or on the ground and sprayed onto the field. Trickle irrigation, a third method, uses an underground system of pipes to water plants directly and is one of the most water-efficient forms of irrigation. Finally, the method of subirrigation utilizes a watertight layer of rock or soil that lies beneath the farm, and water is evenly distributed over this layer and into the roots of the crop.
One of the most common uses for irrigation is literally used right in our own backyards, and that is for the purpose of watering lawns. The device used for irrigating grass is simply known as the lawn sprinkler, and it can come in many different varieties. Some are built under the grass and connected to an automatic timer so they come on at a specific time each day. This is commonly found on golf courses where the quality of grass is essential to the business. Sometimes during an especially dry season, a city or region may impose bans on the amount of water that is used to irrigate lawns for the purpose of preserving the water supply.
Written by Phil Shepley
