What is a Water Footprint?

Your water footprint is the amount of water you use in and around your home, school or office throughout the day. It includes the water you use directly (e.g., from a tap). It also includes the water you use indirectly – this is the water it took to produce the food you eat, the products you buy, the energy you consume and even the water you save when you recycle. You may not drink, feel or see this virtual water, but it makes up the majority of your water footprint. If you examine your lifestyle you can evaluate your water footprint using data that is based on average water use. In fact, water footprints can be calculated for individuals, households, businesses and countries.

Why Do Water Footprints Matter?

Freshwater (non-saline water) is an important and vital resource to ecological and human life, yet as human populations and prosperity grow, so too does our use of freshwater. This is complicated by climate change and the likelihood of a changing water cycle that has already led to periods of “drought and deluge.” Water is already scarce in the world, and a changing water cycle could further constrain our water supplies.

Water footprints help reveal the amount of water being used at an individual level all the way to a national level and in the numerous processes involved in manufacturing and production of our goods and services. An accurate water footprint also takes into account the amount of water contaminated during manufacturing and production because that water is essentially made unusable and, therefore, taken out of the system. While there can never be a perfect water use assessment or audit tool, the water footprint gives everyone – from individual consumers to business managers to public officials – a solid water accounting framework and aids us all in our efforts to be more efficient and conservative with our water use.

What Makes a Blue, Green or Grey Water Footprint?

Water use is measured in terms of the volume of water consumed or evaporated and/or polluted, per unit of time. A water footprint can be split into three elements:

Blue Water Footprint: refers to the volume of surface water and ground water consumed (i.e. evaporated or incorporated into the product) during production processes;

Green Water Footprint: refers to the volume of rainwater consumed (i.e. evaporated or incorporated into the product) by the product; and

Grey Water Footprint: refers to the amount of freshwater required to mix pollutants and maintain water quality according to agreed water quality standards.

Water and energy are closely interlinked and interdependent. Energy generation and transmission requires utilisation of water resources, particularly for hydroelectric, nuclear, and thermal energy sources. Conversely, about 8% of the global energy generation is used for pumping, treating and transporting water to various consumers.

In 2014, the UN System – working closely with its Member States and other relevant stakeholders – is collectively bringing its attention to the water-energy nexus, particularly addressing inequities, especially for the ‘bottom billion’ who live in slums and impoverished rural areas and survive without access to safe drinking water, adequate sanitation, sufficient food and energy services. It also aims to facilitate the development of policies and crosscutting frameworks that bridge ministries and sectors, leading the way to energy security and sustainable water use in a green economy. Particular attention will be paid to identifying best practices that can make a water- and energy-efficient ‘Green Industry’ a reality. Objectives of World Water Day in 2014 Raise awareness of the inter-linkages between water and energy

Contribute to a policy dialogue that focuses on the broad range of issues related to the nexus of water and energy Demonstrate, through case studies, to decision makers in the energy sector and the water domain that integrated approaches and solutions to water-energy issues can achieve greater economic and social impacts

Identify policy formulation and capacity development issues in which the UN system, in particular UN-Water and UN-Energy, can offer significant contributions

Identify key stakeholders in the water-energy nexus and actively engaging them in further developing the water-energy linkages Contribute as relevant to the post-2015 discussions in relation to the water-energy nexus.