AGRICULTURAL IRRIGATION

One of the most common irrigation system challenges is preventing emitters from clogging caused by various organic and inorganic materials. Clogging can severely decrease the irrigation system’s performance and create the need for frequent maintenance.

Our complete range of field-proven agricultural irrigation filters answers the need for clean water for farmers around the world, saving them time, water and energy costs.

Main causes of emitter clogging

Physical: Sand particles and suspended solids that are too large to pass through emitter openings are the most common physical cause of clogging. Silt and clay particles do not generally cause plugging unless they clump together (flocculate) and form larger masses.

Biological: Clogging related to algae and bacteria is common when water with high biological activity is used for irrigation, and is increased when iron, manganese and sulfide are present in the water.

Chemical: Mineral precipitation from water sources with high mineral content (hard water) can produce suspended solids which clog emitters. Mineral precipitation occurs when mineral solubility is low and when factors such as water temperature, pH level, redox potential and mineral concentration in the water are favorable.

Water source and emitter clogging

Emitter clogging varies based on the source of the irrigation water.

Surface water: Generally carries more biological and physical (sand particles) clogging elements. Biological clogging hazards include algae and bacterial growth, which can accumulate to form slime and other particulate aggregates. Larger organisms such as moss, fish, snails, seeds and other organic debris can also clog emitters.

Groundwater: Sand and silt produced at well start-up or from deteriorating wells can cause physical clogging of emitters. In addition, wells producing water with high mineral levels (hard water) can cause mineral precipitation and mineral scaling; and shallow wells (less than 100 ft.) can often be the source of bacterial clogging hazards. Very small concentrations of iron in groundwater can also pose a biological clogging threat.

Reclaimed wastewater: The lack of high-quality water for irrigation and drought conditions often leads farmers to use reclaimed wastewater for irrigation use. Reclaimed wastewater often includes high levels of suspended particles, metal salt ions and biological communities, which can cause the clogging of emitters.

FAQ’s

What are the common causes of clogging in agricultural irrigation systems?

• Physical causes: The most common physical causes of emitter clogging are sand particles and suspended solids that are too large to pass through the emitter openings.
• Biological causes: Bacterial slime can lead directly to emitter clogging of irrigation systems, and it can also cause physical particles to adhere to one another and form aggregates large enough to clog emitters.
• Chemical causes: Mineral precipitation from water sources with high mineral content (hard water) can produce suspended solids which will cause emitter clogging, with calcium carbonate being the most common precipitate.

What preventative measures can be taken to avoid clogging in drip irrigation systems?

• Understand the clogging hazards specific to the source water you are using.
• Test and analyze your source water for the three types of clogging causes (physical, biological and chemical) so that you know what solutions are appropriate to prevent clogging.
• Choose a filtration method based on the clogging hazards detected in the water analysis and emitter characteristics.
• Choose accurate disinfection and water treatment methods to eliminate microorganisms.
• Choose accurate acid injection methods to adjust water pH levels while preventing sedimentation of chemicals and mineral precipitation.
• Periodically flush the system to prevent sediment buildup and organic development in irrigation lines and emitters.

 What factors should be considered when choosing a filtration system for irrigation water?

• Soil: Relatively sandy soils may require more frequent irrigation than clay soils, as clay soils hold moisture longer due to their higher density.
• Layout/ topography: Whether fields are flat, hilly or inclining will have an impact on the best irrigation option.
• Weather: Different climates/weather conditions have an effect on which irrigation technique would be optimal.
• Water availability: Knowing the availability/scarcity and cost of water is essential when choosing the right irrigation system.
• Water source and quality: Where is the irrigation water coming from? Does the water contain high levels of organic or inorganic matter?
• Crop: Different crops require varying quantities of irrigation water to thrive.

What steps can be taken to increase the efficiency of irrigation water?

• Drip Irrigation: Drip irrigation systems dramatically reduce evaporation that occurs with spraying systems, saving up to 80% more than conventional systems.
• Timers: Using timers that schedule watering during cooler times of day to ensures less evaporation.
• Scheduling: An irrigation schedule based on soil type, precipitation, crop requirements, and moisture retention will ensure the most effective application rates and durations.
• Cover crops: Planting cover crops improves the soil and reduces water loss caused by runoff and erosion.
• Conservation tillage: Partially tilling soil to leave behind at least 30% crop residue not only minimizes erosion, but also increases water absorption and reduces evaporation.
• Filtration: Installing a water filtration system reduces clogging, ensures application uniformity, conserves water and saves costs.