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The water footprint of selected UK produced and consumed products - WU0120

Description
The overall aim of this project is to produce water footprints for a range of UK and imported commodities and products. This work will contribute to Defra’s Food Chain Programme objective to reduce the global impact of UK food consumption and production. The recent WWF report (UK Water Footprint) reported that large quantities of water are required to grow and process the food that is produced and consumed in the UK. Water footprints (virtual or embedded water) are useful indicators and this project will calculate them for selected products and assess their impact on UK and overseas water resources.

This project has two discrete, but linked, areas of investigation: (1) To determine the water footprint of UK produced agricultural commodities and relate the water used in production to current water resources; and (2) to determine the water footprint of selected food products which can be produced domestically or imported.

A water footprint is a measure of the virtual (or embedded) water required to produce a product. The concept was introduced by Allan (1998) and has been developed by Hoekstra, Chapagain and others since. Virtual water refers to the amount of water required to produce a product, from start to finish. Virtual water is a mainly neglected and hidden resource and is commonly considered in two categories: blue and green. Blue water is the water contained in rivers and lakes and is the water processed by the water companies to supply public and commercial demand; this water is used in the food processing industry. Green water is the water supplied through rainfall and contained in soils; the majority of agricultural production is based on this water.

The concept of footprinting has been used successfully to describe the impact of production (and consumption); it is most commonly applied to carbon (as in PAS2050 ) but can equally be applied to water. Agricultural production uses large amounts of water; for example, Chapagain & Hoekstra (2004) calculated that, in the Netherlands, it requires 619,000 litres of water to produce a tonne of wheat and 11,681,000 litres to produce a tonne of beef. A recent WWF report suggests that imported food and fibre account for 62% of the UK`s total water consumption.

Food processing, whether it simply washing prior to sale (carrots) or more complicated preparation (preparing a pizza with multi toppings) uses large quantities of water. This is normally blue water, which once used, is sometimes be referred to as grey water; this water (raw or cleaned) is normally discharged to surface waters. However, grey water can also be described as the calculated volume of water required to assimilate emissions (pollution) to the freshwater ecosystem from the production process.

A recent WRAP study revealed that households in the UK discard 5.4 million tonnes of food every year, accounting for around a third of all of the food we buy. This waste food contains large amounts of water, used in production and processing, which is subsequently wasted.

The use of water always has an environmental impact. In water rich countries, like the UK, this is generally hidden, however, in water poor countries, water use can have severe impacts, for example, Morocco, where water demand for horticultural irrigation has lowered the water table to the detriment of future supplies.

This project will prepare water footprints for selected UK produced and imported products and relate those water footprints to available water resources. The project will assess how increasing UK production would impact on domestic and overseas water resources. The work will be split into the following objectives:

1. Assess current water footprinting methodology and determine the best method to use in the study
2. Review recent water footprinting studies and determine the UK and imported products to be assessed in the study
3. Collect data and prepare water footprints for selected commodities and products
4. Explore the relationship between the production of UK commodities and domestic water resources
5. Determine the environmental and social impact of domestic and imported products
6. Assess the potential consequences of climate change on the UK’s water footprint
7. Report on, and discuss, the results and make recommendations for future work
Objective
7. (b) Objectives


The water footprint of selected UK produced and consumed products

The overall aim of this project is to produce, and review the impact of, water footprints for a range of UK and imported food products. This work will contribute to Defra’s Food Chain Programme objective to reduce the global impact of UK food consumption and production. The recent WWF report (UK Water Footprint) reported that large quantities of water are required to grow and process the food that is produced and consumed in the UK. Water footprints (virtual or embedded water) are useful indicators and this project will calculate them for selected products and assess their impact on UK and overseas water resources. The work will be split into the following objectives:

1. Assess current water footprinting methodology and determine the best method to use in the study
2. Review recent water footprinting studies and determine the UK and imported products to be assessed in the study
3. Collect data and prepare water footprints for selected commodities and products
4. Explore the relationship between the production of UK commodities and domestic water resources
5. Determine the environmental and social impact of domestic and imported products
6. Assess the potential consequences of climate change on the UK’s water footprint
7. Report on, and discuss, the results and make recommendations for future work

Time-Scale and Cost
From: 2009

To: 2011

Cost: £161,056
Contractor / Funded Organisations
Warwick - HRI
Keywords
Allocated - WHRI              
Food Security              
Sustainable Farming and Food Science              
Water Quality and Use              
Water Use              
Fields of Study
Water Quality