by Stuart Spaulding,
CLIA Certified Landscape Irrigation Auditor Training & Communications Manager at DIG Corp.


The benefits of utilizing in-line emitter tubing, a.k.a. landscape dripperline, are numerous and well known. The product, (1/2” nominal polyethylene tubing with emitters imbedded into the inner tubing wall at pre-set equidistant spacing), is quite versatile and it’s usage in many landscape irrigation installations is accelerating, and not just because it conserves water.

It is an excellent product to use on slopes, because the high uniformity and low application rate allows for deeper percolation before run-off occurs It’s also a good choice for high traffic areas where overspray might create liability issues, planters and flower beds where plants are densely planted, oddly shaped or curved shrub areas, row crops, areas with constant prevailing wind, and also for small turf areas. The tubing contains UV inhibitors so it can be installed above or below grade.

Perhaps less well known are the technological advances that have recently been incorporated into the emitters design that are intended to improve the short and long term performance of this product.
Some Manufacturers are adding physical barriers to the emitters to prevent root intrusion, others are impregnating the emitter with chemicals to achieve the same goal, and still others are doing nothing in this regard, as root intrusion is not an issue with on-grade installations.

Options are now available that include emitters with built in check valves, so that all emitters open and close at the same time. This function also conserves water by preventing drainage after the system is closed. Most of the emitters incorporated into today’s dripperline are continuously self flushing, rather than flushing only when the system opens and/or closes. An anti-siphon option is also available now, which is intended to prevent reverse suction through the emitters when the system closes, however it is still recommended to install an air relief valve on sub-surface installations.

So now more than ever, it pays to do a little product research, and know exactly what you’re installing, maintaining, or selling. What remains to be seen however is how well these advancements hold up over time.