Irrigation systems in Kenya.
Irrigation is the process of artificially applying controlled amounts of water to crops on land to assist in their production. Irrigation is mainly used during dry periods or in dry areas to grow food crops, maintain landscapes, and revegetate disturbed soils in dry areas. Irrigation also has other uses in crop production, including frost protection, suppressing weed growth in grain fields by only supplying water to the intended crops.
As with any system, there exist various methods of applying the water and they vary as per the water available for use and the type of crop to be grown.
Types of irrigation systems.
There are many different ways to irrigate on your farm, and what you choose will depend on your crops, soil, budget, and water source.
The methods range from the simple and easy, to those requiring the purchase of specialized equipment.
We have listed and explained the various types of irrigation types that are commonly applied in farms. The systems combine a water delivery medium mainly a pipe and a water delivery method like a sprinkler or drip. The irrigation systems vary in how the water is supplied to the plants. The goal is to apply the water to the plants as uniformly as possible in the required proportions, neither too little nor too much.
Surface irrigation systems
Mainly used where water is in plenty and gravity allows irrigation, this is the oldest form of irrigation and has been in use for thousands of years. In surface flood irrigation systems, water moves across the surface of agricultural lands, to wet it and infiltrate into the soil. Water moves by following gravity or the slope of the land.
Where water levels from the irrigation source permit, the levels are controlled by dikes, usually plugged by soil. This is often seen in terraced rice fields (rice paddies), where the method is used to flood or control the level of water in each distinct field. In some cases, the water is pumped, or lifted by human or animal power to the level of the land. The water application efficiency of surface irrigation is typically lower than other forms of irrigation.
Micro/Targeted irrigation systems
Drip irrigation systems.
Drip irrigation/ trickle irrigation works functions simply as the name suggests. The most expensive and difficult system to set up uses pipes that have drip holes or drips where the plant is located. When correctly set up the system has the highest efficiency of between 80-90% in water use and thus cheaper in the long run.
In this system, waterfalls drop by drop just at the position of roots. Water is delivered at or near the root zone of plants, drop by drop. This method can be the most water-efficient method of irrigation and minimizes both evaporation and runoff. The system can be used with timers so that they go on and off at scheduled intervals. The system can be used to deliver fertilizer and herbicides to plants due to their efficiency.
Sprinkler irrigation systems
In sprinkler or overhead irrigation, water is piped to one or more central locations within the field and distributed by overhead high-pressure sprinklers or guns. A system using sprinklers, sprays, or guns mounted overhead on permanently installed risers is often referred to as a solid-set irrigation system.
Lawn sprinkler systems
A lawn sprinkler system is a permanently installed system in residential lawns, in commercial landscapes, for churches and schools, in public parks and cemeteries, and on golf courses. Most of the components of these irrigation systems are hidden underground since aesthetics are important in a landscape. They use pipes to distribute the water and pop-up sprays to irrigate. These systems are expensive but work with timers and hence little to no maintenance is needed. The system can be used to deliver fertilizer and herbicides to plants due to their efficiency.
There are many types of hose-end sprinklers. Many of them are smaller versions of larger agricultural and landscape sprinklers, sized to work with a typical garden hose. Some have a spiked base allowing them to be temporarily stuck in the ground, while others have a sled base designed to be dragged while attached to the hose. They use more water compared to the other systems as they use more water.