PureSense: Irrigation Technology to Live Through Drought


I grew up in Southern California during the beginning of the worst multi-year drought in California’s history. We sang “If it’s yellow, let it mellow. If it’s brown, flush it down” at summer camp. My mother timed my showers and started screaming at the four-minute mark. We cringed at the sight of our azure swimming pool. We thought it couldn’t get any worse.

It is now 2009, and we are officially facing “the worst California drought in modern history” according to Lester Snow, director of the state Department of Water Resources. The Sierra snowpack is 61 percent of what it should be in a normal year, and many water agencies are begin to ration water. This impacts all of us to a certain extent. It means that our lawns will continue to look post-apocalyptic, the mountain rivers we love will be too low for swimming and our produce options will be limited.
California droughts may affect the lifestyles of state residents, but they dramatically impact the agricultural community. Our state produces almost half of America’s fruit, vegetables and nuts. The federal water deliveries this year were the lowest ever.
In the past few years, some farmers have opted to abandon water-intensive plants for more drought-resistant crops. Other California farmers have begun to practice dry farming, a low-impact watering method that utilizes only rainfall. The fruit produced from trees watered only by rain are actually delicious, and are simply a bit smaller and a bit crunchier. Many types of fruits can be grown without surplus water; tomatoes, grapes and apples to name a few.
While some farmers are choosing to go preindustrial and only use rain water, others are choosing to adopt new technologies to advance their water efficiency operations. Enter PureSense, an irrigation software company founded in 2004. PureSense has developed an extremely high-tech method of water efficiency. An electronic sensor is placed in the ground, near the root structure of a tree or plant. The sensor measures moisture in the soil, monitors water moving through the earth and can actually tell when a plant is drinking.
Every fifteen minutes, a solar-powered transmitting station aggregates the soil and weather data from a number of sensors and sends this information to a central console.
A really fancy feature of PureSense’s operating system is an iPhone app. A farmer can check the water content of his soil from anywhere in the world. Trees receiving too much water become sluggish growers. Similarly, trees being starved can stop producing fruit. A farmer’s objective then, is to provide a very specific amount of water to each plant. The iPhone app makes this age-old dilemma almost ridiculously easy.
The system is not cheap. At $5,000 per transmitting station, few of California’s smaller agricultural operations could afford to invest in PureSense’s system. Farmers who have taken the plunge, though, have used less water to produce more fruit. By depriving each plant just enough to get quality results, farmers are able to improve time, resource and financial efficiency. Not to mention the environmental bonuses associated with preserving water.
Richard Gates of PureSense says that his company has two main goals. The first is to allow a grower to be a more intelligent steward of his land. The second is to encourage increased crop yield by using fewer natural resources. Sounds pretty good to me.
PureSense, however, is not the only agricultural option for increasing water efficiency. Some farmers have started using drip irrigation. Others have introduced micro-sprinklers. The agricultural industry has become a bit more resourceful in terms of water usage in the last twenty years. But it is nowhere near good enough. Farmers who don’t adapt to a low-flow farming method simply will not survive in the next twenty years.
As with anything else, adaption is necessary for survival. One thing is for sure: I know I won’t be watering my lawn this summer.

Rebecca Greenberg is an MBA candidate at the Presidio School of Management. Prior to her studies at Presidio, her professional experience was primarily focused in corporate retail merchandising at both Gap Inc. and Williams-Sonoma, Inc. Having traveled extensively in the developing world and having worked in corporate America, Rebecca is very passionate about applying business principles to sustainable development and poverty alleviation. Rebecca.Greenberg@presidiomba.org