Irrigation Best Management Practices
Advanced irrigation technologies, such as low pressure center pivots and subsurface drip irrigation (SDI) systems are good tools, with potential for very high application efficiency. Management and maintenance are critical to maximizing the benefits of these systems.
• Irrigation scheduling: Evapotranspiration (ET) models, based upon weather conditions), soil moisture monitoring and plant-based monitoring are good options. Even better is a combination of methods – ET plus soil moisture monitoring, for instance. Understanding crop water demand with growth stage and soil moisture storage capacity is very helpful to optimizing irrigation management.
• Optimize the benefits of precipitation by reducing runoff losses by using furrow dikes, contour planting and residue management appropriately. Remember that applicability of these practices are site-specific and they are not necessarily universally applicable.
• Consider using LEPA (Low Energy Precision Application ), LESA (Low Elevation Spray Application), MESA (Mid Elevation Spray Application) and SDI, or alternate furrow irrigation to minimize evaporation losses.
• Well designed and maintained equipment will help improve efficiency. Use correctly sized pump and motor to match flow and pressure requirements. Consider variable frequency drives if flows are expected to change. Make sure the system is functioning according to design specifications. Use the correct nozzle package on center pivots. Make sure you have the correct pressure and use pressure regulators where needed. Re-nozzle if needed or if well capacity drops significantly. Check lubrication, gearboxes, etc. Always check basic electrical and mechanical maintenance.
• Zoning in SDI systems allows for flexibility if well capacity drops. Use filtration, flushing and acid injection as needed for SDI systems.