With water conservation now the way of life on the West Coast, growers grasp ever-improving technology to monitor and save every last drop of farming’s “new currency.”
By Thomas Skernivitz, Senior Editor
Once a call is made for “zero percent district water allocation,” there is only so much a grower can do on his or her own ... and for only so long. Such was the case this year for Matthew Sani and other growers in the Alta Irrigation District on the eastern side of California's San Joaquin Valley.
Their problem originated in 2020, when the San Joaquin Valley received a minimal amount of rainfall and recharge for the basin used by Sani’s farm, Sani Citrus, and its 100 acres of mandarin trees. Paired with depleted and already underperforming water basins, every grower within the district was forced to operate solely on pumping well water.
“By the time the issue had become prevalent and detrimental, about half of our operating budget had been spent for this season's crop,” Sani says. “While it would have been nice to retroactively change the inputs and amount of labor spent for our crop, we knew that was not an option.”
As irrigation requirements began to increase in the late spring and early summer of 2021, Sani began to see a drop in pump output and irrigation system pressure. That was not enough to draw huge concern, he says, but, again, in hindsight he knows this was the canary in the coal mine. Over the next few weeks pump output and pressure steadily declined. Sani's deep well began to pump air sporadically.
The immediate issue was that there was not enough pressure for our irrigation system to operate efficiently. Our system requires approximately a minimum of 20 psi at the filter and 11 psi in the field to ensure the emitters are pressure compensated and filters can backwash adequately."
By mid-May the system at Sani Citrus went from pumping 190 gpm to only 85 gpm at 10 psi. At this time Sani sounded the well to find that the static water level had dropped from 35 feet to 85 feet within just five months.
“Our pump was set at 108 feet, and we were pumping what is called falling or cascading water,” he says. “At this point there was a concern that the crop we had set and poured inputs into would have to be abandoned without any access to water. To drill a new well in this area, the wait times are around three to four months, which would put us into October and beyond the irrigation season.”
With time running out, Sani turned to three companies to save his season: Ranch Systems (telemetry and control), Irrigation Matters (irrigation technology), and Eno Scientific (water level sensors).
“Our first approach was to split the system into multiple irrigation sets, which would require less output and pressure,” Sani says.
The Sani Citrus ranch was outfitted with Ranch Systems telemetry, which monitors multiple points in the field, such as filter pressures, flow meters, field pressures, soil moisture, weather, and pump automation. Irrigation Matters provided Sani with hardware while supporting him with any agronomic or technical assistance needed to interpret the data.
“Having access to reliable and sound data has been a life saver during these times,” Sani says. “This paired with remotely monitoring soil-moisture levels in the field helps me connect the feedback loop that water is being applied correctly in the areas that I need it, all while balancing a volatile well water level.”
With an underperforming well and system, Sani says it is crucial to monitor pressures throughout irrigation events.
“In many cases the irrigation event would start out great, but we would lose pressure and flow, causing little to no water applied in the field,” he says. “I had alerts set on Ranch Systems to automatically notify me when I would lose pressure, flow, and a dropping well level. Once I received these alerts, I would remotely turn the pump off and wait for the well to charge back up.”
The second approach to tackling the issue was addition of an ultrasonic well-level sensor provided by Eno Scientific. The sensor was “extremely easy” to install, Sani says, and tied right into Ranch Systems, allowing Sani to capture real-time well-water levels. Readings are taken every 15 minutes, which creates an intuitive way of displaying how an aquifer reacts to an irrigation season.
“What we ended up learning from this was really interesting,” Sani says. “While larger growers in the area irrigated their fields, the static water level would drop down to areas where our pump would not work. While the growers around us turned their pumps off, it allowed the water level to increase to an area that we could irrigate without issues. By the middle of the season, we ended up irrigating on opposite days of others so we could catch the shallower water levels.”
For any grower who does not already rely on telemetry or another means of collecting data on the ranch, Sani has these words of advice: “Do not assume or wait for a problem to occur. Being progressive, proactive, and collecting data during good times will always help you cope and manage throughout the hard times. It is never a bad time to invest in monitoring equipment.”
If money talks, then irrigation is screaming these days.
“For all farmers, water is becoming the new currency,” Steve Baker, the Owner of Circle B Vineyard & Cellars, says. “As such, all will be forced to provide documentation of our usage and pay for it. The real bottom line is that farming is changing, whether we like it or not, and every means we can incorporate into our business will help us to keep up, or we will be out of business.”
A few of those means being used at Circle B, in Paso Robles, CA, involve soil moisture sensors, temperature sensors, and irrigation pressure switches manufactured by Irrometer.
“Speaking from our experience, for crops such as grapes, it is essential to monitor your soil moisture, as it has such an impact on your quality and quantity,” Baker says. “This is another tool in our tool bag to try to keep one step ahead of nature.”
Circle B, while reliant on irrigation from its own water source, with little additional rainfall, needed a better method of monitoring the moisture levels in the soils throughout its four blocks of grapes. Baker had previously relied solely on visual observance of the vines and previous practices, such as irrigating every 10 days and anticipating coming warm periods.
We still rely upon visual observation and watching weather forecasts but now have a better understanding of the moisture content from 12 inches down to 36 inches."
Each of the four blocks at Circle B boasts soil moisture sensors at 12, 24, and 36 inches, a temperature monitor at 12 inches, and an irrigation pressure switch that indicates the time and duration of each specific irrigation.
“We knew there were options available, and the Irrometer system best suited our applications,” Baker says. “In addition, our neighboring vineyard had an older Irrometer system in place, and the accountability of it was what we were looking for.”
Irrigation systems have their imperfections, some more evident than others. What a grower might miss, the technology of aerial imagery is designed to detect. Such a scenario played out this summer at Beckstoffer Vineyards, Red Hills in Kelseyville, CA.
“We use aerial imagery to help improve our uniformity and catch issues with our irrigation system that we didn't already know about,” Padraic Sherlock, the Vineyard Manager at Red Hills, says. “Over the course of a season it's typical to have many different issues with our drip irrigation system that may impact uniformity.”
Damage to a main line has been a common — and major — issue at Red Hills, Sherlock says. The ensuing loss in pressure prevents the impacted block from getting the water it needs. When Sherlock's field teams visually identify the issue, it is usually too late, he says, to stop the water stress from impacting the yield.
Such was the case in June 2021. Aerial imagery manufactured by precision irrigation company Ceres Imaging identified a possible loss of water in the 'Crimson' Cabernet Sauvignon block at Red Hills. Sherlock was alerted to this by a pin in the vineyard's Water Stress Index.
“The pin saw the pattern and identified it as a possible loss of water pressure. Seeing this, we immediately scouted the location and found that a damaged water mainline was to blame,” Sherlock says.
The broken line still allowed water to the majority of the vines, Sherlock says, but there was a substantial loss in pressure along the top of the block. The problem was fixed after it was identified following a June 28 imagery analysis.
We used the aerial imagery on this block to confirm that the crop was transpiring as it should be and not exhibiting the same signs of water stress. We then looked at the canopy cover through NDVI (Normalized Difference Vegetation Index) to look at any lasting impacts from the pressure issue a couple weeks prior. We used this information to help conclude that the impacts on yield were small."
Other issues that can impact uniformity could be caused by human error. Red Hills uses aerial imagery to catch these as well. In August, the technology identified a block in which a valve was inadvertently turned off. The Water Stress Index from Ceres Imaging had a pin in it that showed a rectangular area of stress.
“This was a major uniformity red flag, as we thought this area was being irrigated,” Sherlock says. “We immediately scouted this area and found that the valve needed to be turned on. Luckily, this was an easy fix, and we used the imagery in subsequent flights to ensure no major yield loss was incurred.”
Aerial imagery recently solved two irrigation problems at Bee Sweet Citrus in the Central Valley of California. The first involved plugged emitters. The second revolved around trees on terraces that seemed to lag in growth compared to those not terraced.
“The problems had been ongoing for at least two years,” David Haas, Bee Sweet's Director of Farm Operations, says. “Where we had plugging occurring, we noticed some trees were more stressed than others, even after an irrigation. Where we had terraces, the glaring issue was smaller trees in that area.”
Crop production was substantially lower in these areas. As Haas evaluated the blocks' performances, he focused on discovering the cause of the discrepancies to increase yields and grow uniform trees. In addition, as water has become more regulated, the importance of uniformity has increased.
“If a grower has uniformity issues in the field, I recommend getting data from imagery to identify the real problem,” he says.
Haas turned to Aerobotics to capture data from drone flights. Bee Sweet had enjoyed a previous relationship with the company while estimating fruit in the field.
“With the Aerobotics data, we were able to zero in on the issues and quickly do a follow-up analysis on corrections,” Haas says. “With the in-depth imagery provided, it is easy to get down to an area of the field and overlay the data with maps of elevation and tree health. This helped us in identifying the issues and causes. This service that Aerobotics provided has benefited our ranches greatly, as we are able to provide the right amount of water and address any problems in the irrigation uniformity.”
Have you ever left the house wondering if you forgot to turn off the iron? That sums up how growers typically feel about irrigation during those rare occasions when they must leave their farms during the growing season.
Juliana Moulton runs Evergreen Farm in Brooks, OR. She dedicates her days to growing evergreen blackberries and blueberries. Three years ago, she invested in an automated valve system and soil moisture probes made by WiseConn. Her goal was to be able to move across the field more efficiently.
“I had been losing time and some water with the manual switches,” she says.
This summer, in the clench of an unprecedented heat dome over the Pacific Northwest, the system paid dividends for Moulton while she was on the farm and, more notably, while she was off it.
“With the heat waves of this summer, the acreage and crop needs were very demanding,” Moulton says. “This system allowed me to control the schedule and use those lost man-hours of time as they turned into irrigation time. I was also able to leave the farm, whether it was near or far, a day or possibly more.”
The true test occurred in July. With her berries begging for maximum water, Moulton departed the farm for several weeks because of a family emergency. Enter Bill Terry, the Director of Business Development with WaterPoint Irrigation Technologies. While setting up templates in WiseConn’s DropControl scheduling app to make scheduling easier, he employed a WaterPoint strategy called DIRT (dynamic irrigation recommendation technologies).
The key to DIRT for growers, Terry says, is to begin with treated water – non chemically. The treated-water’s measurably reduced surface tension provides the enhanced absorption required to quickly refill the soil’s field capacities after climate-driven deficits. During July and August, the feeder roots could draw adequate water and nutrients from the soil to maintain berry suppleness during the heat of 2021, he says.
“Bill Terry was able to instruct me on how to make this system work from anywhere at any time,” Moulton says. “Based on what he had found in the probe data, he suggested shorter sets, never more than three hours. This was to essentially layer the water at the correct depths and promote water movement that could be recorded in the charts of the WiseConn system.”
The strategy wound up working, a once-anxious Moulton discovered upon returning to her farm. Her original plan, she says, had been to “push the water deep” to keep saturation constant with a 12-, 14-, and even an overload of a 24-hour set in the more demanding blackberries.
“It was extremely hard to trust that I could get the cane growth I needed with the shorter sets, thinking I was not driving the water deep enough,” she says. “However, Bill established that little to no root activity was deeper than the 28 inches, and I agreed to the shorter sets. My water use was cut by 36% in blackberries and 48% in blueberries. My energy use compared to the prior year was down drastically. I saw no plant stress from reducing the water, and the yield was not comprised or changed at the time of harvest.”
Moulton plans to again use the DIRT strategy in 2022.
“Change is difficult to face when I’m sure my way is working and then someone tells me that I could possibly farm more efficiently. Doubts about agricultural practices and outcomes loom each and every year as I hope that I am making the right decisions for the best yield in the blueberry and evergreen blackberry crops,” Moulton says. “But Bill is committed to following the water journey here and will continue to analyze the data. The system helps conserve water and electricity without compromising plant health or yield.”
Veteran grower Dave Loquaci knows a thing or two about California's irrigation scene. In addition to being the President of Madera Ag Services, a custom farming company that produces wine grapes, dried-on-the-vine raisins, almonds, and prunes, he serves on the board of the Madera Irrigation District.
“So, I want to know exactly what my crop is using,” he says.
In turn, Loquaci has turned to AquaSpy to monitor his properties with 31 soil moisture probes.
“Probes have been around for a long, long time. I'm going to say probably 50 years. But not these kinds of probes,” Loquaci says. “The stuff I was using prior to this worked good, but there were too many wires. Any little thing went wrong. There were too many connections. But these (AquaSpy probes) have been a lot better. Their software is good; their service has been good. It's a multitude of information, I'll tell you. And the screen is really simple to read. Even a farmer can read it.”
John Warmerdam, the Manager of Kings Orchards in Hanford, CA, shares that sentiment. He praises Phytech for its irrigation monitoring technology, which has benefited his 350 acres of stone fruit and 50 acres of almonds and walnuts.
Previously we used sensors to monitor the water content of the soil. While that was helpful, it didn't always translate to what we were seeing in the trees. With Phytech we were able to see the water stress of the tree itself rather than just the amount of water in the root zone. That brought us closer to the actual job we have, which is giving the trees what they want, when they need it. That not only saves us water but also the expense to put it out there and save it for when we really need it, which is invaluable."
The data taken from Phytech’s dendrometer sensors is “all there to see” on an app-based platform that works in real time, Warmerdam says: the seasonal temperature changes, the fruit sizing, and the stress events, climaxing in a year-end evaluation of the efficiency of specific blocks and timings. Without that insight, a California farm such as Kings Orchards would face a constant uphill battle with regard to water conservation.
“Water is always a precious resource. Even when we have a ‘wet’ year and have plenty of surface water available, we need to use it wisely,” Warmerdam says. “Recent ‘dry’ years and the threat of water limitations due to SGMA (Sustainable Groundwater Management Act) have made the need to use our irrigation water efficiently our No. 1 priority. Without water we would not have a crop. Any other input we use can be had at a price, but water is different.”
