Drip Irrigation

1. 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

2. 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.

3. Drip Irrigation

4. 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

5. 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

6. 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

7. 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

8. 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

9. 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.

10. Drip Irrigation

11. Drip Irrigation

12. 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.).

13. 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.

14. 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.

15. 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

16. Thank you! Steven E. Yergeau, Ph.D.Rutgers Cooperative Extension of Ocean County1623 Whitesville RoadToms River, NJ 08755(732) 505-3671yergeau@njaes.rutgers.eduocean.njaes.rutgers.edu