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Why is there a difficult absence of water demand forecasting in the UK?

Image credit: Ralf Roletschek, permission from - Marcela auf Commons.
From August 2015 to January 2016, I was lucky enough to enjoy an ESRC-funded placement at the Environment Agency. Located within the Water Resources Team, my time here was spent writing a number of independent reports on the behalf of the agency. This blog is a short personal reflection of one of these reports, which you can find here. All views within this work are my own and do not represent any views, plans or policies of the Environment Agency.

In a world away from Melanie Phillips and David Bellamy, it is widely accepted that the twinned-spectres of climate change and population growth will likely affect levels of water availability in England and Wales, whilst also exposing the geographic imbalance of water supply-demand dynamics within the country. The Environment Agency has utilised a number of socioeconomic scenarios to predict total demand to change at some point between 15% decrease (if the nation undergoes a transition towards sustainability) to a 35% increase (in a scenario of continued and uncontrolled demand for the resource).

It is within this context that the need to understand future patterns of water demand has become essential for the future resilience of the nation’s water. The Labour government’s Future Water strategy (signed-off by Hilary Benn) 2008 set a national target of reducing household water consumption by 13%. This plan was further incentivised by Ofwat’s scheme to reward companies that reduce annual household demand by one litre of water per property, per day in the period 2010/11-2014/15.

What does our future household water use look like? Whilst per capita consumption will decrease, the number of people using the water grid will increase: resulting in a growth of overall demand. 22 predictions related to public water supply projected a median change of +0.89%. However there are additional complexities: as certain uses of water will decrease, others will increase; as appliances become more water efficient, they will be more likely to be used; and as one business closes, another may join the grid. It is this complexity that creates a great deal of uncertainty in gauging the future water demand of the sector.
Image credit: Nicole-Koehler
But, there exists a problem. Whilst the legally-mandated water management plans of the public water suppliers provide us with a wealth of forecasts of the future water usage within our homes, there exists a lack of available information on the current use of water within many other sectors and how such usage may shift and transform in the years between today and 2050.

This report lays out an extensive review of available literature on the current and future demand of a number of sectors within the UK. It found nine studies of the agricultural sector – with a median projection of 101% increase in water usage. Three studies of the energy sector projected a median decrease of 2% on a 2015 baseline. But, it also found some gaps that restrict our understandings of future water demand.

Want to find out how much water is used in the construction sector? Tough, no chance. The mining and quarrying sector – ready your Freedom of Information request. Want to calculate the future water footprints of our food and drink – prepare to meet that brick wall. If such information is available, it is not in the public domain. Without having a publicly-available baseline, how can we even dream of predicting what our future demand may be?
Crop irrigation.  Image credit: Rennett Stowe.
Water is not just turning on the shower in the morning or boiling the kettle at the commercial break. It is present in our food, our energy and our infrastructure. As a result, it is of the utmost importance that we look to gauge the water use of sectors. Yet, in this regard, we are blind. Although there do exist academic studies and research into the future water demand of the agricultural and energy sectors, this has proved limited and relatively inconclusive, due to the nature of the studies. Furthermore, there is an absence of any such work conducted across the manufacturing and industrial sectors (with the exception of the food and drink industry). This limitation of information makes providing a confident summary of what the water demands of many of these sectors will look like in 2050 highly difficult.

Yes, the key areas of missing research identified in this document do not necessarily equal a lack of information within these sectors – just that such information is either not publicly available or is very difficult to find. It would be unwise to believe that the sectors in question have no understanding of what the future may hold, regarding their water demand. But, in a world of the interdependencies of the food, energy and manufacturing sectors with water usage – it is important for research to know how this nation’s water is used, where it is used and how this demand can be met and/or decreased in an increasingly uncertain future. The food and drink sector is heavily linked to the agricultural sector; the power industry is linked to decisions made within the extractive industries (such as those surrounding fracking); and all are linked to mains water supply and direct abstraction.

These interdependencies and lack of information provide future water demand with even greater uncertainty. Whilst carbon emissions are monitored and water quality is policed, there continues to be a lack of transparency of how certain sectors are using this nation’s water. If this continues in a world that will increasingly be formed of policy and environmental trade-offs, there is a realistic danger that any potential water crisis may be much worse than we expect. 
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This blog is written by Cabot Institute member Ed Atkins, a PhD student at the University of Bristol who studies water scarcity and environmental conflict.

Ed Atkins
Read part two of this blog series Is benchmarking the best route to water efficiency in the UK’s irrigated agriculture?


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