For example, the amount of water that a typical lawn sprinkler uses is measured in gallons per minute -- the standard sprinkler will emit anywhere between one and five gallons four to 20 liters of water per minute.
In contrast, the amount of water that a drip emitter uses is measured in gallons per hour. A well-installed, well-maintained drip-irrigation system all but eliminates the phenomenon of water wastefully running off.
Sign up for our Newsletter! Mobile Newsletter banner close. Mobile Newsletter chat close. Mobile Newsletter chat dots. Mobile Newsletter chat avatar. Mobile Newsletter chat subscribe. Lawn Care. Simcha was an Israeli engineer and inventor who lived between and Simcha was an important figure in water development in Israel and he, with his son, initiated, introduced and developed drip irrigation systems.
Drip irrigation was tested in a primitive form in the 's but the modern technology as we know it was properly developed by Simcha in the 's in Israel.
Its discovery seems to have been something of an accident. Blass, whilst spending some time in the desert regions of Southern Israel noticed something strange. He noticed that one tree near his location was performing much better than all other vegetation nearby.
When Blass went for a closer look, he noticed that a water pipe near the tree had a small leak supplying its root system with its very own regular slow supply. This accidental discovery led Blass to embark on a journey of trial and error testing various materials and water pressures for an ideal solution.
It wasn't until the 's with modern plastics that Blass could take his technology to the next level. In the 's Blass was able to finalize the technology and patent the design. Drip irrigation systems are pretty simple setups but do consist of several constituent parts. A typical simple system will consist of the following components.
Simplified drip irrigation system [Image Source: IrrigationTutorials ]. The role of valves in the drip irrigation system is very simple. They turn the water flow on or off. Valves come in various "flavors". Isolation valves are manually operated for systems that require an infrequent shut-off of the water. These valves are typically sited close to the water supply to enable isolating the system for repairs or off season. These can be installed anywhere in the system to enable isolation of segments of the system for localized repairs but this is usually only employed in larger systems.
Control valves are valves that turn the water on and off to individual "circuits" or areas of the yard that are perhaps irrigated separately from one another. These can be automatic using solenoids or manually operated. Depending on the system design there can be just one or many installed. For instance, you may have one control valve that controls water supply to the emitters in a vegetable garden.
Yet another may be present that controls water supply to shrubs or hanging pots around the house and patio. Drip irrigation system [Image Source: Wikimedia Commons ].
This is a piece of kit employed within the system to prevent, hence the name, dirt, bacteria, other contaminants from being sucked back up into the drinking water supply for the drip system. This device is essential for all drip irrigation systems.
Backflow preventers are essential because drip emitters rest directly on the soil and are potential very susceptible to water contamination from soil born diseases etc. These devices, as the name implies, reduce the pressure of water flowing through the system and keep it at a constant level. Pressure reducing valves and pressure regulators are in this instance synonyms and essentially the same thing.
Drip irrigation systems, on the whole, perform best at lower water pressures than typical water supply systems. These devices also enable a constant system pressure even if the supply pressure fluctuates periodically, which is nice. Designers need to be conscious of areas with low water pressure as these devices will clearly further reduce the system pressure.
Usually, two types of pressure regulators are employed in drip irrigation systems. Non-adjustable ones with pre-set outlet pressures and user adjustable types. In general, small homeowner system will use non-adjustable valves if they have less than 3 control valves.
You can, of course, install adjustable valves if you want full control of your system. Non-adjustable regulators must be installed after the control valve and in cases where multiple control valves are present, pressure regulators are needed for each one. Accidental installation before the control valves can cause pressure surges that will damage the system.
Adjustable pressure regulators, on the other hand, can be installed before or after the control valves. In large systems, you can install a single or fewer adjustable pressure regulators in the main supply line before control valves to save on costs. The filter is obviously used to, well, filter the water.
Drip emitters have very small openings which are easily clogged up so employing filters earlier in the system is essential for increasing the life span of the irrigation system. Recommendations for filters are that they are between and mesh.
High-quality filters are often installed before the valves or pressure regulator but lower quality ones can be installed after the pressure regulator. High-quality filters usually have a maximum pressure rating of Now we come to the "guts" of the drip irrigation system. The emitters are responsible for directly controlling the rate of water supply to the soil. Emitters are usually small plastic devices that either screw or snap onto the drip tube or pipe.
In trickle pipe systems they are pre-assembled and part of the pipe assembly. Common emitters, emit, water at around 4 liters per hour. As a general rule of thumb 1 or 2 emitters are usually required per plant. This does, of course, depend entirely on the size of the plant in question. Trees or shrubs will clearly need more than a small plant. Use of multiple emitters also provides the system with backups in case of a blockage in one or more of the emitters.
The more emitters present the wider the area of irrigation and hence the increased growth of roots for healthier crops and plants. Of course, if plants tend to be planted close together the system may only need 1 per plant depending on the system design and "coverage" of the emitters. Emitters are usually installed at least mm apart.
For highly permeable soils emitters should be placed to mm apart. Emitters should never be buried unless they are specifically designed for this purpose. This pipe is the main connection between the water supply to the control valves of the drip irrigation system. The combined length of the mainline and sub-main should not exceed feet. The valve controls water flow into the system and can be set for either automatic or manual control.
Pressure regulators are needed if the water pressure is over 40 pounds per square inch. If you do not know your water pressure it is a good idea to install one just in case.
Filters keep dissolved substances in your water from clogging the emitters over time. Install filters either at the emitters or at the water source to protect both the valve and pressure regulator in addition to the emitters.
It is best if the filter has at least a mesh screen or higher. Tubing adapters and fittings are used to attach the drip tubing to the rest of the system. It is important that these are the right size for the tubing to prevent them from blowing apart under pressure.
Drip Tubing and Emitters Drip tubing is a polyethylene tube with emitters placed along the plants. The emitters release the water from the drip tubing. Drip tubing and emitters come in various types and diameters depending on your needs. The length of a single drip tube should not exceed feet from the point where water enters the tube. You will need to stake the tubing to keep it from moving. This helps to prevent clogging and rodent damage. Emitter Spacing and Design Emitters can be spaced evenly for row crops, and this design is known as an emitter hose.
Emitters can also be spaced intermittently for plants spaced further apart, such as trees, shrubs and perennials. With an emitter hose, the emitters will generally be spaced about 18 inches apart. When watering trees and shrubs, there should generally be two emitters per plant. The end cap is placed at the end of the drip tubing to prevent water running out the end. Basic Operation and Maintenance Drip irrigation can be set to run automatically, like sprinklers, or controlled manually.
Manual operation allows you to take advantage of rainfall before applying unnecessary water. For more information on proper watering, see Water Wisely. Because small amounts of water are applied slowly, drip irrigation is designed to run daily unless it rains. Water is applied either once or twice a day.
Early morning is the best time to water because there will be less evaporation.
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