Satellite control of company and municipal irrigation systems, based on custom weather data, saves billions of gallons of water nationwide
In Silicon Valley the Campbell Union School District‘s sprinklers used to dutifully water the soccer fields and gardens at 12 campuses even during spring showers. Temporarily shutting off each of the 45 irrigation control boxes, by hand, wasn’t worth the custodians’ time. But in 2009 the district installed new “smart” controllers that automatically adjust daily watering to the weather. Each box, fitted with a microprocessor and antenna, receives local real-time weather information by satellite from the WeatherTRAK climate center supercomputer run by Petaluma, Calif.–based HydroPoint Data Systems, Inc.
On one April morning after a three-day rainstorm, Campbell Union’s facilities supervisor, David Radke, checked the status of the controllers by logging in to WeatherTRAK.net The service had put the district’s irrigation network on pause when the storm began, and according to WeatherTRAK’s math, the network would not need to resume watering for eight to 11 days.
If needed, Radke can reprogram the controllers from his Web account, but because his crew has carefully customized each box’s settings, he finds that “there’s really not a whole lot to do. That’s the beauty of it.” The soccer fields look better than ever, yet in 2009 WeatherTRAK slashed Campbell Union’s water use by 39 percent and cut its utility bills by $108,000, recouping the installation expenses nearly twice over.
With most sprinkler systems, property owners set the traditional controller—basically a timer—to irrigate at specific intervals. Often, too much water is lost to evaporation during hot weather or to runoff during cool weather, which can also carry chemicals into the local watershed or ocean. Because outdoor irrigation can suck up 50 percent or more of urban water consumption, smart irrigation services have caught on in drought-prone western states like California, where water prices are relentlessly rising. (Occasional big floods don’t help the long-term problem.) HydroPoint now has more than 8,000 clients using 24,000 of its smart controllers, including Walmart, Coca-Cola, Hilton, Jack in the Box and the University of Arizona as well as the cities of Charleston, S.C., Houston and Santa Barbara. In 2011 customers are projected to save 64.4 billion liters of water and over $111 million in water expenses, as well as 68 million kilowatt-hours of water-pumping electricity.