Smart Irrigation Can Save Billions of Gallons of Water, Energy

A recent article written for Reuters News Service describes the massive potential to save water--and energy--through smart irrigation controllers, such as weather- or sensor-based systems that reduce over watering.

According to the article(which was picked up by Forbes, EcoSeed and Scientific American, among others):

Americans can save some of the 225 billion gallons of water (852 billion liters) wasted each year through over-watering by installing smart systems which deliver just the right amount of moisture.

Homeowners and companies over-water their grass and plants by between 30 and 300 percent, said Chris Spain, chief sustainability officer at water management company HydroPoint, citing a report by the American Water Works Association.

"The reason for the waste is because of dumb technology," Spain said. "There are 45 million irrigation systems in the U.S. (controlled) by simple timers. They do a great job of keeping time but a lousy job of irrigating to what the land requires."

City landscaping, or "urban irrigation," makes up 58 percent of urban water use, Spain said, adding that the water wasted generates over 544,000 tonnes of greenhouse gases annually.

The article also mentions the significant energy and carbon emissions reductions that can be acheived through smart irrigation technologies. Of course, as my astute readers will observe, here at River Network we already know the energy-related figures cited in the article:

"U.S. water-related energy use is at least 521 million megawatt hours a year -- equivalent to 13 percent of the nation's electricity consumption," said a River Network Carbon Footprint of Water report published in May.

"The carbon associated with moving, treating and heating water in the U.S. is at least 290 million tonnes a year."

The potential to save water by installing improved irrigation systems is real and the article cites a number of case studies to back up the lofty claims made by promoters of irrigation control systems. First. there are golf courses which have seen savings between 18 and 20 million gallons per year from irrigation control systems.

Compared to timer-based irrigation systems, installing weather- or sensor-based systems (which have comparable costs) typically result in water savings of between 16 and 30 percent. A spokesperson from Rain Bird, a manufacturer of irrigation products, explained that her company saw a corporate client cut their water use by nearly half--from 416,000 gallons per year to 214,000 gallons.

These huge savings have not gone unnoticed by the EPA, which has issued draft specifications for weather- or sensor-based irrigation control systems through its WaterSense program.