While nearly all modern agriculture requires some amount of supplemental irrigation, viticulture is particularly high in water demand. Figures vary depending on the source, but studies claim anywhere from 10 to 30 gallons of water goes into a single gallon of finished wine. This figure combines both irrigation and the cleaning water used for sanitizing bottles and tanks. Naturally, the use of water depends on both controllable management decisions and uncontrollable natural conditions. Discover what’s behind the high demand for water at wineries, and how to control usage in every category, to make the most of every gallon.
The largest use of water at most wineries and vineyards is for irrigating the grapes themselves. Of course, wineries that only order in grapes or juice, rather than growing them, eliminate this water demand. Vineyards definitely use the majority of their water for irrigation, especially if there’s little to no actual winemaking on site that produces cleaning wastewater. Poor soil conditions limit the absorption of both natural and irrigation water, causing you to apply too many gallons to keep the soil moist and leading to losses from runoff and evaporation. Improving the soil’s condition with cover crops, mulch, and amendments that add organic material, can all help water penetrate and stay in the soil without negatively affecting vine growth. If the vineyard is covered with weeds or water-competitive turf grass varieties, removing them with shallow tilling and herbicide use can ensure water makes it to the grape roots instead.
Cleaning and Processing Water
Cleaning and processing demand during the winemaking and fermentation process is the second largest use of water by most wineries. For facilities with little to no vineyard space for growing, almost all of the water used by the facility may go to these steps instead. Since wine requires sensitive fermentation processes, relying on specific strains of yeast for the desired flavor profile, thorough cleaning and sanitizing is required at every step. Bulk fermentation tanks and final storage tanks are cleaned out before and after each use, along with all the equipment used for transferring the liquids. It’s hard to minimize water usage for sanitization, since it can threaten the safety of the operation. However, switching to steam and UV systems can reduce some of the water required for washing. Basic practices, like turning off hoses while scrubbing and using high pressure spray nozzles to get more cleaning power, also go a long way. If this water use can’t be significantly reduced, most wineries can still try to reuse it as irrigation water by running it through a treatment pond system. After treatment in a lined and aerated pond, the water is often clean enough to add back to existing irrigation ponds.
Reuse and Efficient Use
To lower water usage as much as possible and make a winery as drought-proof as possible, you’ll need to combine both reuse opportunities and efficient use techniques. Reusing wastewater won’t necessarily provide everything a vineyard needs to thrive with irrigation, so it’s essential to ensure that as much water as possible from each gallon makes it to the roots. Efficient irrigation may require a complete redesign of the current system. Sub-surface irrigation was installed in the 1990s and early 2000s in many California vineyards in an attempt to beat evaporation and prevent moisture issues with the soil surface and leaves. However, these buried lines are prone to filling with sediment or attracting plant roots that destroy them and cause costly leaks. For most vineyards, above-surface drip or micro-spray emitters are usually the most efficient choice. Switching from sprinklers or pivot sprayers to drip lines could reduce water use for irrigation from 10% to 30% or more; depending on the specific conditions. When planning for ponds that must hold hundreds of thousands to millions of gallons of irrigation water, using a little less can translate into big savings.
Frost Control with Winter Sprinklers and Sprayers
Irrigation water is generally in the highest demand during the hot, dry parts of the active growing season. For California, and most other North American wine cultivation areas, this is anywhere from June to September. Yet, there’s also a need for a steady water supply throughout the winter in some areas, for sprinkler-based frost control. Wine grapes don’t like exposure to hard freezes and cold winter temperatures and sensitive buds can easily die back during a late frost in the spring. Using sprinklers for irrigation can encourage disease and leaf damage, but they’re ideal for coating leaves with water to protect them from cold temperatures. As ice forms on buds and leaves, the heat generated by the phase shift protects the plant from damage. It’s a complex, yet low-tech way to deal with unexpected weather changes, but it relies on generous supplies of clean irrigation water even in the winter and spring.
Growing Grapes in Drought Prone Areas
With the varieties of grape most commonly grown for wine preferring a light and sandy soil, it’s not surprising that many vineyards are located in drought-prone areas. Whether the grapes are growing in Australia, California, Chile, or Ontario, they’re at risk for drought stress and may generate huge demands for water when it’s the least available. It’s also a common misconception that the best regions for grapes never have to irrigate. Even regions in Italy and France known for their dry farming techniques still rely on wells and irrigation ponds during long periods of drought. Dozens of conditions go into the specific amount of water needed by any one grape vine, including its variety, soil health, average temperatures, recent weather patterns, and hours of sunlight exposure.
On-site Water Gathering and Storage
Most wineries and vineyards can’t solely rely on wells or existing irrigation canals to keep up with the demand for irrigation water. Digging storage ponds, gathering rainwater, cleaning wastewater, field runoff, storm water, and any other convenient source of safe water is a valuable tactic for preparing for future droughts. Wells that tap into major aquifers face stress from nearby agriculture and can run dry unexpectedly. A surface pond at least gives you a visual indication of how rapidly the water is being used up during the growing season. Even if your winery currently relies on a public water supply for both irrigation and cleaning, adding on-site water storage and reuse is always a good idea.
Wineries that work on reducing water use and reusing wastewater will find they have a new marketing angle for their products. Customers are starting to learn about how high agricultural water demand for is affecting the environment. You can expect interest in water-smart wines to grow over the next few years, along with the demand for touring these kinds of facilities. Start working on your new irrigation ponds now by discussing your plans with our team here at BTL Liners.