Ask the Expert: 7 Common Issues and Solutions that Embrace Smart Irrigation Technology

The Irrigation Association has promoted July as Smart Irrigation Month since 2005. This is an effort to highlight water conservation and healthy landscapes through sound irrigation practices that embrace advances in technology. We’ve connected with Dave Shane, Central’s Commercial Irrigation Sales Manager, to learn more.

From: Dave

This is an update to an article I wrote for Smart Irrigation Month, 2022.  The article addressed the common problems I’ve observed that are preventing our industry from reaching higher levels of customer satisfaction.  Not surprisingly, the last twelve months have been more of the same.  However, some key recent project calls have caused me to add a new # 1 issue not previously addressed.

Below is my new problem list, along with common sense solutions, in order of importance from my perspective. 

1. Missing or incomplete as-built documents

This is critical on large, complex decoder sites, but is a real problem for all types and sizes of projects.  Invariably, a new contractor takes over system maintenance and can spend months, or even the first season trying to determine the location and routing of the two-wire paths, the location of decoders and their addresses, and even the number of points of connection.

Owners often become frustrated when asked to foot the bill for an as-built before the new contractor can begin to determine the extent of the problems and estimate the cost of repairs.  The typical fallback is to continue running the system as it was in the past, which is often wasteful of water, labor, plant health and usability of open spaces.  This perpetuates the poor reputation our industry has for larger projects.

As-builts should be a requirement for all commercial projects.  I suggest never taking on a new maintenance project without first reviewing the accuracy of the as-built, if it exists, or agreeing with the owner on the cost of creating an as-built. And remember Central is here to help as a reliable partner if you want to tackle this problem more efficiently, just ask your rep!

2. Existing central control systems that are not used to their full potential

Overwatering and seldom changing runtimes are common problems despite the availability of smart controllers and increased awareness of plant water requirements. This is directly related to problem # 1 – with so much critical information missing, it is difficult or impossible to make informed decisions on correct zone runtimes.

Consider using soil moisture sensors to control irrigation cycles. They work differently, depending on the specific sensor and controller. Some are like a rain sensor, stopping the irrigation cycle when a moisture level is reached. Others are more sophisticated and can start the cycle when a low moisture level is reached.  Determining the quantity of sensors and their locations is critical to success.

Consider using smart controllers. These controllers access cloud-based programs and can change runtimes based on local weather. They remove the guesswork and the need to go to the controller to make manual changes.

3. No way to stop high flow

Broken mains and laterals are a chronic problem, wasting water, ruining landscapes, and creating liability. The fix is simple – upgrade to controllers that use flow sensors to compare actual to expected flow.  Most commercial controllers available today can determine if high flow is the result of a mainline or lateral break.  Be sure to add a master valve to shut the water source in case of a mainline break.

4. High system pressure

This is the most common field problem I see on site visits.  High pressure causes misting, poor distribution and wasted water. The cure is pressure regulation. A regulator can be installed on the mainline at the point of connection.  Pressure regulators can be added to the master valve or zone valves.   Pressure regulating spray and rotor heads are available for new projects and can be retrofitted on existing projects.  Regulation as close as possible to the nozzle is always the most efficient method.

5. Using the same nozzle in all rotors in a zone

This works if all the rotors have the same arc, but typical zones are a mixture of various arcs.  If the quarters use 1.5 nozzles, the halves should use 3.0 nozzles and the fulls should use 6.0 nozzles. Dry or wet spots within a zone may be caused by mismatched nozzles.  A simple solution is to audit the zones – record the rotor arcs and their nozzles.  If they are mismatched, change them out so that all heads contribute relatively the same amount of water to a given area.

6. Spray and rotor heads in the same zone

Their precipitation rates are very different.  Like # 5, mismatched precipitation rates in the same zone will result in dry or wet spots. The solution is to change out either the sprays or rotors, so the zone is all one or the other.  Changing rotors to sprays may require additional heads.  A more costly option is to add an additional zone valve to separate the two types of heads.

7. Stretched head spacing

Spacing should be no greater than head-to-head and should often be less, depending on wind conditions.  Stretched spacing is obvious and results in dry spots during the peak season. The easiest solution is to install larger nozzles.  This may work if the pressure and volume are adequate, but you may be restricted by existing pipe and valve size.  A more difficult solution is to add heads and move the existing heads to create correct spacing.  Again, you may be restricted by existing pipe and valve size.  It may be necessary to add a zone if additional heads are necessary.

Finally, let’s again make July Smart Irrigation Month by creating more efficient, more intelligent irrigation systems, from the nozzle to the controller. Better yet, let’s+ resolve to create Smart Irrigation Year and Smart Irrigation Decade for a more prosperous industry as regulation-free as possible. If you have questions, reach out to your local Central rep. We’re here to help you grow efficiently and profitably!

About Dave Shane

Dave has more than three decades of experience in the irrigation industry in both distribution and manufacturing roles. He specializes in commercial project solutions with an emphasis on controls to meet complex requirements. He is an excellent resource for any technical questions about irrigation systems and finding the right solutions for efficient irrigation systems.