Irrigation – “the science of artificial application of water on the land or soil.” The first signs of irrigation, and therefore of agriculture, appeared about 10,000 years ago, and the early phase of drip irrigation around 6000 BC. Previously people were Hunter Gatherers, who collected their food from what they would find around them. Often these people were nomadic, followed the game and the vegetation, which in turn followed the seasons. Although there are still hunter-gatherer communities today, the vast majority of the world’s population now relies on agriculture and agriculture for their livelihood.
According to the Geological Survey of the United States, almost 60% of the fresh water in the world, from wells, rivers or lakes, goes to the irrigation of crops for both humans and animals. As the world’s population explodes more than 7 billion people, the need for quality food grows. This is a tax for the water supply of the world. According to the Food and Water Watch Foundation, 1.4 billion people live without clean drinking water. How can we justify many of today’s irrigation practices where so much fresh water is wasted through evaporation and drainage?
As early as 6000 BC, many societies used irrigation, often based on flooding during the rainy season, and harvesting water during the rest of the year. Archeology has shown that precolumbian America, Sub-Saharan Africa, Persia (modern-day Iran), Egypt and China, to name but a few, developed water collection systems, dams and extensive networks of irrigation channels already built in 4000-6000BC. The first evidence of the use of drip irrigation was also found around this time period. Clay pots were buried in the ground and filled with water, which would slowly seep into the surrounding soil where crops were planted.
Modern drip irrigation was in its infancy in 1866, when farmers and researchers in Afghanistan started using clay pipes for both irrigation and drainage. Although a professor at Colorado State University in Ft. Collins, E.B. Huis, experimented with the application of water directly on the roots of plants as early as 1913, he came to the conclusion that this system was too expensive, and the practice went out of the boat. With the invention of plastic tubes it started to change. Saker snakes and drip tapes were used in the 1960s, but the problem was that they would soon be blocked by the minerals in the water. Ironically, the driest places on earth, which require the most drip irrigation, tend to have the hardest water that contains the most minerals, which in turn clog the system.
With the invention of the sprayer in the 1930s, agriculture and agriculture were given a completely new aspect. Now vast areas with dry prairie can be planted with a variety of water-hungry crops. With the arrival of Center Pivot Irrigation, more land was irrigated above ground, where evaporation and wind drain a large percentage of the water before it reaches the roots. Who has not looked out of a plane window while flying over infertile land, only to see hundreds or thousands of perfectly round circles of bright green, only to wonder how much water it has needed to accomplish this feat.
The most valuable innovation in modern agriculture is probably the perfection of the drip irrigation system. Although the most efficient form of drip irrigation is the underground emitter, there are some applications that require micro spray nozzles. As the agricultural techniques continue to evolve and the water supply decreases, the underground systems can take over very well. In order to be able to drain water to the roots, the only part of the plant that needs moisture would yield enormous water savings. It is estimated that traditional forms of irrigation are only 30-40% efficient. In the current era of drought, climate change and population growth, wasting even a liter of water is a mockery; and the situation is getting worse every year.
While drip irrigation was once considered important for desert agriculture, it also gained popularity in semi-arid and sub-moist zones. For those parts of the earth that are blessed with an abundance of moisture, especially rain during the growing season, this is not a problem; because this zone is only a fraction of the total arable land on earth, dripping is what agriculture and agriculture will make or break now or in the future. There may be some drawbacks to drip irrigation, such as blockage of pipes, degradation of plastic in the sun and initial costs, but the benefits far outweigh those