(Wines&Vines) - As water is expected to become even more costly and scarce in coming years, winery wastewater ponds may soon turn from an unsightly necessity to a helpful source of usable water.

While wineries have been taking advantage of treated municipal wastewater for years, most have not taken full advantage of the wastewater generated from cellar operations. A pair of studies by researchers at the University of California, Davis, confirms winery wastewater is a potential source of irrigation water as long as care is taken to best understand the how the treated wastewater will interact with vineyard soils.

Maya Beulow, a researcher with the UC Davis department of Land, Air and Water Resources, said she organized two studies associated with winery wastewater as part of her master’s thesis. Interested in the ongoing drought and growth of the U.S. wine industry, Beulow said she wanted to contribute some research about exploring reusing water.

In her study, published in the American Journal of Enology and Viticulture and funded by the Kearney Foundation of Soil Science, Beulow and co-authors Kerri Steenwerth, Lucas Silva and Sanjai J. Parikh collected and analyzed samples of untreated and treated wastewater from 18 wineries in Sonoma County and the California cities of Ukiah, Napa, Lodi, King City and Paso Robles each month for nearly two years. The samples were analyzed for pH, electrical conductivity, cation and anion concentrations, specific ultraviolet absorbance, dissolved organic carbon and biological oxygen demand.

 The wineries participating in the survey use a variety of treatment systems from basic aeration ponds to complex tertiary treatments that mimic wetlands and activated sludge processes. All of the wastewater was found to be nontoxic for vines, Beulow said.

One potential area of concern, however, is sodium, which gets to the wastewater stream through cleaners and is not removed with wastewater treatments. Beulow said many wineries are switching to potassium-based cleaners to avoid this issue.