Understand the nuances between these two concepts
Check the following comparative table (Table 01) to understand the differences between water consumption and water scarcity within BCome methodology.
Table 01. Differences between water consumption and water scarcity.
| Indicator | Water consumption | Water scarcity |
| Unit | liters | m3 water eq |
| Methodology | – | AWARE |
| Definition | Water or “blue water” consumption refers to the amount of water directly consumed in the product value chain, including fresh surface and groundwater, such as water in freshwater lakes, rivers, and aquifers. | Water scarcity is a relative concept based on the fact that water is a finite resource. Indeed, the amount of water that may be accessed varies according to supply and demand. When demand rises and/or the quantity or quality of the water supply declines, there is an increase in water scarcity. Therefore, any activity requiring water (such as almost any product value chain) has a negative effect on water scarcity since it automatically deprives water to either humans or ecosystems. |
| How is it calculated? | Water consumption in the value chain is calculated by summing the estimated or measured water consumption of all the processes included in the boundaries of the product system. | Water consumption in the value chain is first estimated (see water consumption). Then, it is multiplied by a characterization factor comprised between 0 and 100 which is based on the water scarcity of the geographical area as well as on the type of water used in the value chain. The characterization factor can be read as follows: – Value = 1: world average. – Value < 1: water is less scarce than the world average. – Value > 1: water is more scarce than the world average. |
| Benefits | – Easy to understand. – Globally recognized indicator. | The methodology is recommended by widely recognized organizations: – The UNEP-SETAC Life Cycle Initiative. – The PEF/OEF Program of the European Commission. – The International EPD system. It represents the real estimated impact of consuming water in arid areas. |
| Drawbacks | – This is not an impact indicator. – Does not account for water availability. | – Hard to understand at a first glance. |