Farmers in the arid Southwest are turning to aquaponics, an indoor system that combines hydroponics with fish farming to conserve water and use fish excrement to nourish plants, reports The Guardian.
“I’ve tried everything you can to grow crops [in Nevada] and you can’t do it profitably,” said Mark O’Farrell, the owner of Hungry Mother Organics in Minden, Nevada, east of Lake Tahoe. He estimates that the 32,000-square-foot greenhouse he’s building to grow tomatoes, peppers and fish will save him $12,000 a year while slashing water use by 80 percent. O’Farrell anticipates opening his farm, which will produce as many as 50,000 tilapia annually, in August.
“Although fish require copious amounts of water,” says The Guardian, “the same water can be used multiple times to irrigate crops and in some cases, even improve soil quality with the addition of nitrogen and potassium from fish waste.”
The need for such efficiency in water use is obvious and growing. Beyond the immediate drought, The Guardian reports that “a recent study in Geophysical Research Letters found the Southwest, including parts of California, has entered a ‘drier climate state,’ and is not just experiencing isolated, temporary periods of drought.”
Advocates of aquaponics have been pushing for conventional farmers to either follow O’Farrell’s lead or partner with fish farms to share water and nutrients. “The number of farms producing fish in Arizona nearly doubled between 2005 and 2013, according to the 2013 Census of Aquaculture,” The Guardian says.