11.1.1 Water use

Water use by organisations is a huge subject area, but the focus here is just as an input into organisations.

The total volume of water on Earth is estimated to be about 1.4 billion km³, of which about 2.5% is freshwater (35 million km³). Nearly all of this freshwater is in the form of ice/snow or ground water, leaving very little (less than 1%) readily available to ecosystems in lakes, rivers and other surface water bodies (UNEP, 2012a).

Human freshwater use has been growing significantly, increasing at twice the rate of population increase in the twentieth century. For example, in 60% of European cities with more than 100 000 people, groundwater is being used at a faster rate than it can be replenished (UNEP, 2012b).

Of the freshwater used by humans, about 70% is used for irrigation, about 22% for industry and about 8% for domestic use. Working on the basis that irrigation is often done by small family-type organisations, we can estimate that anything between 50 and 90% of freshwater used is used by organisations of some sort (UNEP, 2012b).

You can see some of this information more easily in Figure 13.

adapted from UNEP, 2012a and 2012b

Figure 13 Global water resources and use

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This figure consists of four images. The first is pie chart showing total world water, of which 97.5% is saltwater, the remainder freshwater. A second pie chart shows the proportions of freshwater in different states: 70% is ice and snow cover in mountainous regions, 30% is groundwater and 0.3% is freshwater in lakes and rivers. The third image is divided in half, the left part showing one person with five bottles of water below as a scale of water use, and the right part showing two people with 13 bottles of water. This image shows that the rate of water use is growing faster than the rate of population increase. The fourth image is a pie chart showing the breakdown of freshwater use: 70% for irrigation, 22% for industry and 8% for domestic use.

Global water resources and use

Collectively, UK water companies supply 17 billion litres per day of drinking water and handle 16 billion litres of wastewater per day (WaterUK, 2012). This is equivalent to approximately 8500 Olympic-sized swimming pools (where 1 billion litres = 500 Olympic swimming pools).

Figure 14 The swimming pool contains 1/8500^th of the daily water supply in the UK

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This is a photograph of an Olympic pool as an aid to understanding the volume of water supplied daily in the UK.

The swimming pool contains 1/8500^th of the daily water supply in the UK

Drawing resources from the environment on this scale can have impacts on river systems, groundwater and species, depending on where and the type of habitats the water comes from. In recent decades, many habitats and species in the south east of England in particular have come under pressure in terms of surface and groundwater availability, as shown in Figure 15.

EA, 2010, p. 14

Figure 15 Water resource availability in England and Wales, 2010

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This figure shows a map of England and Wales, which is colour coded according to the availability of water resources over time. Five shades of blue are used to represent availability – lightest being less available and darkest almost always available. The five categories are less than 30% of the time, at least 30%, at least 50%, at least 70% and over 95%. Although there is a complex overlay of colours, in essence, the south east area of England and parts of East Anglia are light blue, mid-Wales, Midlands and Northern England medium blue, and westerly coastal regions predominantly darker blues.

Water resource availability in England and Wales, 2010

A similar picture is emerging elsewhere in Europe and globally. Figure 16 shows water stress in Europe in 2005 and projected forward to 2050 under an ‘economy first’ scenario. The stresses equate to centres of population shown in the map on the right.

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EEA, 2012

Figure 16 Water stress indicator for annual average on river basin level for the 2005 baseline (left), for 2050 under ‘economy comes first’ scenario (middle) and compared with urban population numbers (right)

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This figure shows water stress in the European area. It is subdivided into three parts – each showing a map of river basins in Europe. The detail is less important than the overall picture and so the following description equates the river basins to countries.

The first map is a baseline in 2005 showing current water stress. Low water stress is indicated for central France, northern Spain, Scandinavia, parts of Ukraine, Poland and a swathe of Balkan states. Medium water stress is indicated for southern Spain, northern European countries in an arc from France/Belgium down to the Black Sea; and much of Italy. High water stress is shown for north-east and eastern Spain, south east England, Belgium/Netherlands, parts of Central Italy and parts of Greece.

The second map is a predicted scenario for water stress in 2050 where economic prosperity is prioritised. This map shows considerable increase in water stress from the first map. Few areas, except Scandinavia are now indicated for low water stress. High water stress areas have increased in number, including large swathes of England; all of the northern Europe industrialised countries, Switzerland, much of Italy and the western seaboard countries of the Black Sea.

The third map shows current population of different cities in Europe using proportional circles. The main point to be understood here is that much of the current and future water stress levels shown in the previous maps correspond to high levels of urban population, particularly cities in excess of a million inhabitants.

Water stress indicator for annual average on river basin level for the 2005 baseline (left), for 2050 under ‘economy comes first’ ...

These water stress maps reveal the pressures on resources, but do not show the additional impacts arising from the energy and resources used to abstract, store, purify and supply the potable water, and then deal with the resulting waste water.

These figures and maps are high level. But the dependency of organisations and business on sustainable environmental inputs are receiving increased scrutiny, with at least one recent survey suggesting that water security (e.g. drought and flooding) was a major concern, impacting on business operations for an increasing number of the largest 500 global companies (Brown, 2012). At the level of an individual organisation this can be significant. A car manufacturer, for example, uses a significant volume of water, with estimates of 50 to 80 m³ (50 000 to 80 000 litres) of water required per car in manufacturing (Berger et al., 2012), although this estimate could easily be doubled or trebled depending on manufacturing processes and efficiencies.