Mr. Danie Erasmus grows pasture crops for his cattle at Winkelhaak Boerdery, a dairy farming operation in Tsitsikamma, South Africa. Like many farmers today, he has faced the challenges of unpredictable weather and extended dry seasons.  

Danie’s concerns with the dry and windy conditions during the 2020 season prompted him to install LESA (Low Elevation Spray Application) sprinklers on one of his pivots, following recommendations from Mr. Pieter Rens at Irrico, a Senninger dealer in the Eastern Cape region.

“We’re incredibly proud that our products help increase productivity while reducing water dependencies for our customers. Water is becoming an increasingly valuable resource for the agricultural sector. Investing in more efficient sprinkler components on center pivots can provide significant advantages, especially when it comes to savings in water and electricity” said Gerhardus Bower, Senninger’s Area Manager in South Africa.

Danie Erasmus explained to Gerhardus, “There are often challenges to get enough water into the soil profile, especially with the unpredictability of electrical power supply in South Africa due to load shedding. LESA sprinklers allow us to manage our irrigation scheduling according to wind conditions, water, and electrical availability. We can achieve the same irrigation requirements in less time, which is a major advantage for our operation. During the recent dry season, combined with high wind speed conditions, we certainly noticed the increased efficiency of LESA packages versus conventional sprinklers.”

Saving Water and Energy with LEPA and LESA Irrigation

LEPA (Low Energy Precision Application) and LESA (Low Elevation Spray Application) systems can operate at lower pressures ranging from 0,4 to 0.7 bar and typically require applicators to be installed as low as 50 to 70 cm above the ground. Both methods save water and energy when compared to conventional irrigation systems. These systems can also increase yields when installed according to specific parameters.

LEPA installation involves bubble applicators that save water because the distribution avoids tiny droplets prone to wind drift. According to the University of Idaho Extension, this installation typically reduces evaporation losses by at least 10 to 15% compared to conventional sprinkler installations, especially during high temperatures, high winds, and low humidity.

 LESA systems use non-bubble applicators, generally sprays, installed no higher than 50 cm above the soil surface. LESA is a modification to the typical way of mounting sprinkler heads on center pivots that helps minimize losses due to wind drift and evaporation.

The suitability of one method over another depends on the farmer’s needs. In areas where LEPA is more common, farmers prefer this technology for its benefits of water savings. Texas A&M AgriLife Research states, “Application efficiencies were 70 to 80% for LESA systems and greater than 90% for LEPA systems.” Meanwhile, researchers at UC Davis find LESA presents “fewer problems with non-uniformity, crop germination, or with ponding and runoff […] and therefore can be more flexible with a wide variety of crops, row orientations, and tillage systems.”

LEPA/ LESA Sprinklers from Senninger Irrigation

Senninger offers several types of LEPA applicators depending on the pattern: Wide Spray Bubble for a large diameter of coverage, Beige or Red Bubble Inserts with a Shroud to deflect water down in a gentle dome, and a cascading Bubbler distributing water as a narrow stream. These models are designed for easy conversion to spray irrigation when needed. All farmers need to do is twist and flip the deflector. Farmers can then use the spray side of the deflector pad for germination or LESA.