Drip Irrigation February 22, 2017 Steven E. Yergeau, Ph.D. Farm Energy Efficiency & Water Conservation Seminar Rutgers Snyder Research Farm Drip Irrigation February 22, 2017 Steven E. Yergeau, Ph.D. Environmental & Resource Management Agent, Ocean & Atlantic Counties Rutgers Cooperative Extension of Ocean County Slide 1: “Welcome. I will be talking today about drip irrigation and it’s benefits to efficient water use.”

Drip Irrigation Drip irrigation (also known as trickle irrigation or microirrigation) is a method that allows precisely controlled application of water and fertilizer by allowing water to drip slowly near the plant roots through a network of valves, pipes, tubing, and emitters. Slide 2: “Drip irrigation (also known as trickle irrigation or microirrigation) is a method that allows precisely controlled application of water and fertilizer by allowing water to drip slowly near the plant roots through a network of valves, pipes, tubing, and emitters. A typical system set up us shown here. There are many components of a drip irrigation system which start at the well and end with the crops.” Photo Credit(s): Wikimedia Commons (https://commons.wikimedia.org/)

Drip Irrigation Slide 3: “Drip irrigation systems can also be rather simple. The systems shown here uses 5-gallon buckets to hold the water which then slowly travels through the drip lines to each of the plants.” Photo Credit(s): Wikimedia Commons (https://commons.wikimedia.org/)

Drip Irrigation Advantages High water application efficiency Low runoff potential and low evaporative loss; ~90% of the water reaches the plants Reduced water use Watering directly to the plant requires ½ - ¼ of volume of water Source water supplies can be smaller than other irrigation types Weed and disease problems may be reduced because drip irrigation does not wet the row middles or the foliage of the crops as does overhead irrigation Less energy used to run pumps Slide 4: “A drip irrigation system has many advantages over other types of irrigation systems. They provide high water application efficiency. Drip irrigation systems have low runoff potential and low evaporative losses. Because of this about 90% of the water reaches the plants. They have reduced water use. Watering directly to the plant requires ½ - ¼ of the volume of water of other irrigation systems. The source water supplies can be smaller than other irrigation types because of the lower volumes used. Weed and disease problems may be reduced because drip irrigation does not wet the middles of crop rows or the foliage of the crops as does overhead irrigation. Less energy is used to run pumps because of the reduced volume utilized.”

Drip Irrigation Advantages High degree of automation Application may be simply managed and programmed with an AC- or battery-powered controller, thereby reducing labor cost Field operations can continue during irrigation Highly adaptable Drip systems are adaptable to oddly shaped fields or those with uneven topography or soil texture, thereby eliminating the underutilized or non-cropped corners and maximizing the use of available land Slide 5: “Other advantages include a high degree of automation where the application may be simply managed and programmed with an AC- or battery-powered controller, thereby reducing labor costs. This also means that field operations can continue during irrigation, especially since there is no water splashing onto farm workers and equipment. The systems are highly adaptable to oddly shaped fields or those with uneven topography or soil texture, thereby eliminating the underutilized or non-cropped corners and maximizing the use of available land.”

Drip Irrigation Disadvantages Higher cost Systems typically cost $500–$1,200 or more per acre Annual cost of disposable parts can run 2-10% of system cost Extensive maintenance Requires properly designed filtration and pressure regulation Leak repair can become a large investment of time and money; lines can be easily cut or damaged by tilling, transplanting, or manual weeding with a hoe; or damage caused by insects, rodents or birds High-quality source water needed Risk of clogging due to sediment, iron, bacterial growth in lines; possible addition costs due to chlorination of water Slide 6: “There are some disadvantages to using drip irrigation systems. There is a higher cost to these systems which typically cost $500–$1,200 or more per acre due to the various components of the system. Annual cost of disposable parts can run 2-10% of system cost which is higher than in other types of irrigation systems. They require extensive maintenance. Drip irrigation requires properly designed filtration and pressure regulation equipment. Leak repair and equipment replacement can become a large investment of time and money; lines can be easily cut or damaged by tilling, transplanting, manual weeding with a hoe, or damaged by insects, rodents or birds. They also require high-quality source water. There is a large risk of clogging due to sediment, iron, and bacterial growth in lines and the emitters. There is also a possible additional cost to chlorinate the source water to improve water quality.”

Design Considerations Drip Irrigation Design Considerations Water Supply Water quality is usually the most important consideration when determining whether a drip irrigation system is physically feasible Well and surface water can contain high concentrations of undesirable minerals and sand Surface water can contain organic debris, algae, bacteria, soil particles, and other material In designing a drip irrigation system, the water supply first should be tested to properly plan the needed components to prevent emitter clogging Slide 7: “When planning to use drip irrigation, there are some design elements to consider. The first and foremost is the water supply. Water quality is usually the most important consideration when determining whether a drip irrigation system is physically feasible. As mentioned in the previous slide, the water supply needs to be of high quality. Well and surface water can contain high concentrations of undesirable minerals and sand, organic debris, algae, bacteria, soil particles, and other materials that can lead to clogging and breakage in the system’s components. In designing a drip irrigation system, the water supply should be tested first to properly plan the needed components to prevent line and emitter clogging.”

Drip Irrigation Water Sampling An essential part of drip-irrigation management is determining water quality through water testing Water testing will help determine water chemical composition, pH, and hardness These parameters have direct implications on chlorination, acidification and filtration needs for irrigation water These tests are designed to test water suitability for irrigation; they do not indicate whether water is suitable for human consumption Slide 8: “An essential part of drip-irrigation management is the quality of the source water. The best way to ensure there are no issues with the source water is to have a water sampling plan. Water testing will help determine water chemical composition, pH, and hardness. These parameters have direct implications on chlorination, acidification and filtration needs for irrigation water. These tests also are designed to test water suitability for irrigation and whether there is the potential for clogging. Note that these tests do not indicate whether water is suitable for human consumption.”

Drip Irrigation Monitoring of irrigation water, both at the source pump and in the field, of a drip irrigation system for ferrous (soluble) iron, total iron, and turbidity was performed during 2015 at a blueberry farm in southern New Jersey. The objective of the monitoring was to determine the potential risk of clogging to the irrigation system from high iron and turbidity levels. Slide 9: “As an example of monitoring a drip irrigation system, I performed monitoring of irrigation water, both at the source pump and in the field, of a drip irrigation system for ferrous (soluble) iron, total iron, and turbidity during 2015 at a blueberry farm in southern New Jersey (Atlantic County). The objective of the monitoring was to determine the potential risk of clogging to the irrigation system from high iron and turbidity levels.” Photo Credit(s): Steve Yergeau, Rutgers Cooperative Extension of Ocean & Atlantic Counties

Drip Irrigation Slide 10: “This photo shows an example of a typical set up for drip irrigation at a blueberry farm. The water is delivered directly to the plants root system through the network of tubing and emitters. For the farm I worked on, there are over 250 acres of active blueberry production on drip irrigation. This size farm needs a way of determining if there is the potential of clogging to prevent costly repairs in the future.” Photo Credit(s): Wikimedia Commons (https://commons.wikimedia.org/)

Drip Irrigation Slide 11: “This map shows an overview of the blueberry farm. Note where the source water is at the pump (blue water drop). We tested the water at the pump and different fields during the growing season. Different fields were monitored depending on which ones were undergoing active irrigation at the sampling time (which was weekly). The fields highlighted in yellow were sampled at least once during the growing season. This shows that we had a good representation of the entire farm by covering many fields.” Photo Credit(s): Steve Yergeau, Rutgers Cooperative Extension of Ocean & Atlantic Counties

Drip Irrigation The iron concentrations measured at the pump and in the fields indicate a potential for clogging the drip irrigation system. Iron can turn into a solid form (ferric iron) under the proper conditions and cause physical clogging of the drip irrigation system’s components (pipes, emitters, filters, etc.). Slide 12: “The iron concentrations measured at the pump and in the fields indicate a potential for clogging the drip irrigation system. The photo shows successive samples from the same drip line for one field. The increasing orange color shows an increasing mount of iron in the line. Iron can turn into a solid form (ferric iron) under the proper conditions and cause physical clogging of the drip irrigation system’s components (pipes, emitters, filters, etc.).” Photo Credit(s): Steve Yergeau, Rutgers Cooperative Extension of Ocean & Atlantic Counties

An Ounce of Prevention Conduct regular visual inspection of the plants for signs of lack of water (i.e., wilting and/or dry, browns leaves) and visually inspect the soil for dry areas adjacent to drip lines and emitters as indicators of clogging. Keep a record of the date, location, and number of visual inspections and a description of what was observed, similar to the records kept for integrated pest management activities on the farm. Slide 13: “Based upon our monitoring, there are a couple of steps that growers can take to ensure the proper functioning and efficiency of their drip irrigation systems. We recommend conducting regular visual inspection of the plants for signs of lack of water (i.e., wilting and/or dry, browns leaves) and visually inspecting the soil for dry areas adjacent to drip lines and emitters as indicators of clogging. We suggest that growers keep a record of the date, location, and number of visual inspections and a description of what was observed, similar to the records kept for integrated pest management activities on the farm.”

An Ounce of Prevention Periodically visually inspect the irrigation water in the field and flush the ends of the drip lines, by opening the lines during irrigation, to remove any build up of iron particles and other debris that can lead to clogging. Keep a record of the date, location/field, and number of times that water in the drip lines were inspected and flushed. Perform routine cleaning and/or replacement of filters at the pumps in the irrigation system to reduce sediment and other debris, as indicated by the turbidity levels observed during the sampling period. Slide 14: “We recommend that growers periodically visually inspect the irrigation water in the field and flush the ends of the drip lines, by opening the lines during active irrigation, to remove any build up of iron particles and other debris that can lead to clogging. And to keep a record of the date, location/field, and number of times that water in the drip lines were inspected and flushed. A simple step is to perform routine cleaning and/or replacement of filters at the pumps in the irrigation system to reduce sediment and other debris, as indicated by the turbidity levels observed during the sampling period.”

Drip Irrigation Resources NRCS New Jersey Irrigation Guide https://www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs141p2_018247.pdf USDA NRCS Energy Consumption Awareness Tool: Irrigation https://ipat.sc.egov.usda.gov/ Using Irrigation Water Tests to Predict and Prevent Clogging of Drip Irrigation Systems (RCE Fact Sheet) http://njaes.rutgers.edu/pubs/publication.asp?pid=FS793 Slide 15: “There are a few resources available to growers who wish to get additional information on the design, use, and maintenance of their drip irrigation systems.”

Thank you! Steven E. Yergeau, Ph.D. Rutgers Cooperative Extension of Ocean County 1623 Whitesville Road Toms River, NJ 08755 (732) 505-3671 yergeau@njaes.rutgers.edu ocean.njaes.rutgers.edu Slide 16: “Thank you for your time and I’ll take any questions you may have.” Photo Credit(s): Wikimedia Commons (https://commons.wikimedia.org/)