Planning and Installing Irrigation Systems for Longevity and Easy Maintenance

By Eddie Rodieck

Irrigation systems are seldom installed with consideration for future maintenance, repairs and taking into consideration future growth of plants and trees.  Employing the right techniques and materials during irrigation installation will add longevity and ease of maintenance for future repairs. Here are a few pointers when it comes to installing new irrigation systems that will last for years and offer more manageable maintenance.

Irrigation System Options

The two most common options for homeowners and commercial property owners when it comes to irrigation systems are poly-drip irrigation lines and PVC multiport systems. Both have advantages and drawbacks so these should be considered when investing in a new irrigation system.

Poly-Drip Irrigation Lines

For years, poly-drip lines have been used to allow plants to be successfully watered on a slow-drip irrigation system. This eliminates flooding and allows for the deep watering of root systems for plants, shrubs and trees. This is especially important in the Sonoran Desert where water is not always readily available in the top layers of soil. Such deep watering periodically throughout the summer and winter months allows shrubs and trees to grow strong, deep roots to maintain healthy growth and remain upright during strong winds.

One of the most common issues with poly-drip irrigation lines that can occur is that after four to five years, the tubing can develop cracks and can begin leaking. Typically, the life span of these poly-drip irrigation lines is about 10-15 years before the irrigation system should be replaced. A longer span than that can lead to excessively high water bills as frequent leaks and water damage may become an issue. The lines may also become damaged over time by the growth of roots that can also lead to leaks in the system.

PVC Multiport Systems

Similar to drip irrigation lines in that they deliver water to plants on a regular schedule, these systems differ due to the rigid PVC that is used to construct them. The lines and outlets used to supply water to the plants are contained in small, round irrigation boxes which helps to prevent roots from entering the irrigation lines.

While generally more expensive to install than poly-drip lines, this is the system Cherry Landscape usually recommends as the investment up front is well worth it in the long run. The PVC multiport system, if installed properly, typically lasts much longer than poly-drip irrigation systems. Repairs, if needed, would be to replace the multi-port drip irrigation regulators which are located in the round irrigation boxes. The repairs are often quite simple with this type of irrigation system as one simply needs to remove the lid and unscrew the emitter to replace it.

Installation Considerations

Poly-drip lines are flexible lines run in close proximity to larger trees and the plants that they are irrigating.  Issues that eventually occur with poly-drip systems is that the roots of larger trees and shrubs can create the following problems:

  • Roots can kink the poly irrigation lines which are more malleable than PVC, preventing water flow and causing you to water more frequently due to the lack of pressure in the irrigation line.
  • Shrub and tree roots may also penetrate irrigation lines through outlets and couplings causing low pressure issues.
  • Roots can even grow into the poly irrigation lines causing water flow restriction and more frequent watering as a result of low pressure.

With multiport lines, the chances of roots growing into the system and disrupting water flow are greatly diminished. This is due to the heavier structure of the PVC itself which is more rigid. This means PVC lines are less susceptible to being kinked by roots of larger trees and shrubs. Additionally, the multiport system is encased in the valve box housings which further prevent roots from growing into the outlet and clogging the system.

Sleeving Issues & Solutions

One of the considerations often overlooked when installing poly-drip irrigation lines and/or PVC multiport systems is the replacement of irrigation lines underneath driveways, sidewalks, and in planters. The sleeving, which houses the irrigation lines underneath concrete driveways, inside planters in industrial complexes, etc., are often buried approximately 2-foot to-3-foot deep. Accessing the irrigation lines in the sleeving for repairs is time consuming. In most cases, when the sleeves are encountered, they are filled with gravel, dirt, and the roots from matured trees that have penetrated the sleeving making the replacement of the irrigation lines and sleeving itself impossible due to the roots that have grown inside.

A simple solution to the sleeving problem when installing a new system is to integrate the sleevings into irrigation boxes. While this is not an industry standard, it allows for easy access to the sleeves just by removing the lid, disconnecting the irrigation lines, and running the new irrigation lines through the sleeving through access valve boxes on either side.

Sleeving for Planters

Planters are typically installed around buildings with raised planters installed around office complexes, apartments, etc. Irrigation lines and sleeving are installed at grade and planters are filled with dirt and trees and shrubs are planted on top of them. This makes repairs next to impossible and often results in having to remove mature trees and shrubs inside the planters to initiate a simple repair.

If the sleeving in these planters is installed in valve boxes, repairs are much simpler. All one must do is remove the lid, disconnect the irrigation lines, cut the irrigation lines, and run new irrigation lines through.

These simple tips in preplanning your new irrigation systems can add longevity and help you maintain your watering system through many years with minimal expense.

For more information about irrigation systems, their installation, or maintenance, please contact Cherry Landscape at (520) 292-9776.