Water Use Intensity of Canadian Beef Production in 1981 As Compared to 2011

The amount of beef produced per animal in Canada has increased significantly from 1981 to 2011 as a result of changes in production efficiency and increases in carcass weight, leading to a decrease in greenhouse gas and ammonia emissions per kilogram beef. This study examined the impact of improvements in production efficiency on water use intensity during the same time frame. The study employed a cradle-to-farm gate life cycle analysis taking into account temporal and regional differences in cattle categories, water use for drinking and feed production, feeding systems, average daily gains, and carcass weight. Water use intensity was defined as the amount of water required to produce one unit of beef. Water use coefficients for each feed crop and pasture type were employed to estimate water consumption associated with feed production for beef cattle. Harvest and feeding losses were also included in the analysis. Estimates of drinking water consumed by a given class of cattle accounted for physiological status, body weight and dry matter intake as well as ambient temperature. Approximately 70% of the drinking water in both years was consumed by the breeding herd (cows, bulls, replacement heifers and calves). In both years, drinking water accounted for less than 1% of total water use when precipitation for feed crop and pasture production were included in the analysis. When precipitation (i.e., green water) was excluded from the analysis, drinking water accounted for up to a 25% of total water use for Canadian beef production. The estimated intensity of blue water use (surface and groundwater) per kilogram of beef at the farm gate was 467 L in 1981 and 395 L in 2011, representing a 15% decline. The observed reduction in water use intensity over the past 3 decades may be attributed to an increase in average daily gain and slaughter weight, improved reproductive efficiency and reduced time to slaughter. Given that feed production accounts for a significant portion of water used in beef production, further improvements can be achieved by increasing feeding efficiencies and reducing water use per unit feed crop and pasture production.