The average amount of water needed to produce one kilogram of beef is the sum of the direct and indirect sources of water consumption. The direct cost is the water that the animals consume as drinking water. Indirect sources of cost, however, are water used in livestock buildings and meat processing (process water for cleaning animal rooms, carcasses and equipment, etc.) and feed production.
In areas with a temperate marine climate (Estonia, for example), drinking water for animals is the major factor influencing the amount of water in beef production (estimated at 25-30 liters per kilogram of meat produced). The amount of technological water is also of the same order. As there is no need to irrigate pastures (grasslands) and exist sufficient amounts of natural precipitation in this climate zone, the amount of water used to produce feed is practically zero. In continental climate zones where the average temperature during the growing season is higher and the air drier (less rainfall), grassland irrigation is widely used. As a result, the total water consumption required for beef production can increase several thousands of times.
Source: Livestock's long shadow environmental issues and options