Water to wine in wineries in Portugal Douro Region: Comparative study between wineries with different sizes

Wine production, one of the oldest industries in the world is an industry for which water use in winery operations is often disregarded of best practice, with many managers unconscious how water is used within their operations. Given the economic and cultural significance attributed to wine production in Portugal and in the world, it is crucial that research be undertaken to understand how water is used in wine industry in order to increase the efficient use of this vital resource. The study aimed to measure, evaluate and discuss the water consumption in three wineries with different production volumes. Results showed that there are clearly two distinct seasons in the consumption of water: a low season (from November to August, sensu lato), with reduced consumptions, and a high season, corresponding to the harvest/first racking period (September/October), a period in which water consumption is multiplied by a factor 2-3 in the smallest wineries, or by a factor 5 in the larger ones. Outside the harvest period, consumption shows a linear evolution in all wineries. During the harvest/first rackings season (September/October), consumption increases, showing an exponential evolution, with around 35 to 50% of annual water accumulated consumption (as shown in A and B wineries mainly). In fact, results show that the quantity of wine produced influences, above all, the specific consumption of water (l of water per l wine produced), benefiting large wineries due to the greater scale economy. The values founded for the specific consumption of water are still very high, and that lives a field for research to look for specific measures of efficiency in the use of water in this type of industry.