Blue Water Footprints of Ontario Dairy Farms

Mariam Al-Bahouh,Robert Gordon,Mike Dixon,Tom Wright,Andrew Vanderzaag,Vern Osborne

doi:10.3390/w13162230

Abstract

The blue water footprint (WF) is an indicator of freshwater required to produce a given end product. Determining the blue WF for milk production, the seasonal water use and the impact of water conservation are important sustainability considerations for the dairy industry in Ontario (Canada). In this study, a water footprint network (WFN) method was used to calculate the seasonal blue WF’s from in-barn water use data and the fat–protein-corrected milk (FPCM) production. Various water conservation options were estimated using the AgriSuite software. Results showed that the total water use (L of water·cow−1·d−1) and the average blue WF (L of water·kg−1 of FPCM) were 246.3 ± 6.8 L·cow−1·d−1 and 7.4 ± 0.2 L·kg−1, respectively. The total water use and the blue WF could be reduced to 182.7 ± 5.1 L·cow−1·d−1 (25.8% reduction) and 5.8 ± 0.1 L·kg−1 (21.6% reduction), respectively, through adaptive water conservation measures as the reuse of the plate cooler and milk house water. For example, conservation practices could reduce the milk house wash water use from 74.3 ± 8.8 L·cow−1·d−1 to 16.6 ± 0.1 L·cow−1·d−1 (77.7% overall reduction).

Highlights

Dairy farms are considered to be water intensive production systems due to their significant fresh water requirements [1]
The blue water footprint (WF) is an important sustainability indicator related to milk production
The outputs of this study showed that the total water use (L of water·cow−1·d−1) and the average blue WF (L of water·kg−1 of fat–protein-corrected milk (FPCM)) were 246.3 ± 6.8 L·cow−1·d−1 and 7.4 ± 0.2 L·kg−1, respectively

Summary

Introduction

Dairy farms are considered to be water intensive production systems due to their significant fresh water requirements [1]. The expansion of dairy production to support the increasing global demand for milk and milk products has created further pressures on water resources and competition between the water and food supply sectors [3]. It is, important to quantify the rate of water use and the water footprint (WF) of dairy production systems to assist with better understanding, quantifying and improving the sustainability of the sector [4]. We focus on the blue WF that addresses the direct on-farm water requirements to produce milk (i.e., the fat–protein-corrected milk—FPCM)

Objectives

Methods

Conclusion