A few years ago, T.J. Rodgers was using about 4 inches of water per acre annually on his vineyard near Woodside, Calif. For the past two years, however, the tech entrepreneur and winegrower has cut his water use on his 1-acre vineyard down to 0.2 to 0.8 inches annually.
"Last year, my vineyard was completely autonomously watered," Rodgers says. "The field asked for water, and the system gave it water, and there was no human intervention. I've done that for two years now."
Rodgers is doing this through a WaterBit automated irrigation system, which includes soil moisture probes, cloud computing and a Block Valve Controller that can be used to automatically turn on valves in drip-irrigated blocks that need water.
Rodgers, WaterBit chairman, is well-known as the founder and former CEO of Cypress Semiconductor — a manufacturer of different kinds of silicon chips, circuits and microcontrollers.
More recently, he's delved into viticulture, and WaterBit marks one of Rodgers' latest forays, marrying his love of winegrowing with the tech sector.
The WaterBit system has been available since 2018, but new components are being released in 2019. The company is now expanding its footprint in the Great Plains and Midwest.
The system uses capacitance probes, although other sensors — including leaf water potential sensors — likely will be added in the future. The probes take readings at six depths throughout the day.
It takes data from the capacitance probe and, using a solar-powered Carbon node, sends it to a gateway via a long-range radio connection. The gateway has a 4G connection to the cloud, and a Carbon node can communicate with a gateway over distances up to 1.5 miles, even through vineyard foliage.
When combined with WaterBit's Block Valve Controller, this communication can be used to remotely schedule irrigation and control the flow of water to different blocks in a drip-irrigated field or vineyard.
The user also can connect to WaterBit's Pressure Sensor to validate irrigation system health. In the future, irrigation recommendations based on sensor data will be added.
With the Block Valve Controller, valves are self-controlling. That is, valves can be programmed to turn on and off depending on certain criteria — such as soil moisture levels.
In the three years since Rodgers began using the WaterBit system, he's significantly changed his irrigation strategies. In his 1-acre vineyard on the central California coast, he's gone from three zones to six to more precisely manage water.
By monitoring soil moisture levels and leaf water potential more closely, he's also cut back on the amount he's watering.
"My typical watering used to be four hours, 2 gallons per vine,” he explains. “I found a lot of the water was percolating through the root zone and I was losing it. Today, my waterings are an hour, which is a half-gallon per vine maximum. If I need more water, I just water more often."
After first installing the system in 2016, Rodgers says he simply watched soil moisture levels before trusting and using the information to irrigate in 2017. In 2018, he programmed the Block Valve Controller to automatically turn on valves when certain trigger points are met, effectively automating the system.
He encourages growers to do the same. After installing the probes, producers should get familiar with how volumetric water content and water use change in different parts of the fields based on their normal decisions and based on what the probes are telling them — and adjust.
"They will 'rewire' their system like I've done in my vineyard," Rodgers says. "By the third year, they'll trust the ground reading because they're looking at it for the third year in a row. They're getting trust they can turn on the water, and trust the system will turn on water the right amount of time and then turn it off."
WaterBit is field-testing a Flow Meter Logger to provide real-time data on the volume of water pumped. It is expected to be available by the end of this summer.
It's not just being used by winegrowers in California, but also on farms in the Midwest in corn, wheat and soybean fields. While the cost of the system varies depending on the size of the irrigation blocks, the goal is to keep the cost per acre at less than $100.
"At first we thought grapes and nut trees would be it, but now we're finding out the economics works out for almost every crop," Rodgers says. "We've been able to connect the value proposition on a lot of different crops."