No matter where you are located, the next irrigation season is either upon us or will be upon us. Some systems may have been completely drained and winterized, while others may have simply been used less. Regardless, the start of a new irrigation season is a good time to review the operation of the system and take note of whether it is performing as intended. It is also a good time to review the basic principles of why we irrigate the landscape and how systems are designed for best performance using the best practices.
Let’s start with a quick review of the hydraulics of an irrigation system. The goal is to properly manage the pressure available to make sure we have a close to ideal amount of pressure available for us at the emitters or sprinklers to help ensure the best possible uniformity. Factors such as the size of the pipe, fittings, valves, etc., are going to limit the amount and impact of pressure losses. The speed that water is moving and the length of the piping runs will have an impact. Even the materials used for piping and components will have an impact. When you are activating the system, it is important to consider all these principles when observing the system operation and hydraulic performance.
“The principles of hydraulics, electricity, layout and scheduling should drive every tech decision in the field.”
When opening the isolation valves, if the system was drained, did you take care not to fill the pipes too quickly? Is the source of water fully available, or are there any restrictions limiting flow? Is the pressure consistent for each of the watering areas? If not, what could be the cause? Too much flow required (leaks, multiple stations activated, poor nozzling choices, etc.)? Piping restricted? Changes in elevation that were not considered? Did something change since the last time the system was operated?
The principles of electricity are like hydraulics, except we are managing the amount of voltage losses so that there is an adequate amount available to make sure the solenoids open (and that could be AC or DC). I am a proponent of at least annual measurement of the controller and wire paths’ electrical performance to proactively address or anticipate any issues. Although system activation may not allow for the time needed to troubleshoot and repair any electrical problems, make sure to at least start the process by measuring voltage output and resistance and noting any possible changes to the electrical system, the source or the landscape that might have contributed to any issues with the electrical performance of the system.
Most of us are familiar with the strategies of proper head and drip-tubing spacing and layout, and, typically, we quickly notice if they are inadequate. Although the initial design may have been adequate, remember that the landscape may have changed dramatically over the years due to maturation, usage, changes or other factors. The season start might be a good time to remind the property owner or manager that the irrigation system may need to be adjusted and adapted to the current landscape.
And lastly, let’s remember the basic premise of why landscape irrigation systems exist: to provide the supplemental water needed for plant health when enough water is not available from natural precipitation. When setting up schedules for early season, make sure run times reflect the amount of supplemental water needed, and make sure that all sensors that can interrupt the watering schedule for rainfall, weather conditions or adequate soil moisture are present and functioning properly.
Regardless of whether you are activating the systems yourself or if you are responsible for a team of technicians activating thousands of systems, make sure to revisit, remember and reinforce the basics. The principles of hydraulics, electricity, layout and scheduling should drive every tech decision in the field. It is easy to get caught up in the latest and greatest controller technology or new tool for the technician or newest and best sprinkler ever made, but let’s not lose sight of the real reasons why we are doing what we do.
