An evaluation of alternative water footprint methodologies using an indicative tissue paper supply chain

There are two methods to calculate a water footprint; volumetric and impact assessment. The aim of this study is to evaluate these alternative water footprint methodologies using a New Zealand-based tissue paper supply chain. It was found that for the reference flow of one kilogram of tissue paper the volumetric water footprint was 1762 kg and the impact assessment footprint was 0.32 kg (as ecosystem water-equivalents). The results indicate that whilst the water associated with tissue paper production in New Zealand is large the impact of this water use is minimal. Both methods are limited by a lack of data and consistency. The volumetric method requires clearer delimitations and the impact assessment method used cannot claim to fully quantify the impacts of the water use using the current indicators and criteria. Therefore it is recommended that a single, more inclusive water footprint method that uses more sophisticated indicators of water stress is developed.