5. How pressures on water use are predicted to change over time (dynamics)

Current research has expanded our knowledge of how water is currently used and what the resultant pressures are on the water environment. Over time this use will change as technology and the underlying economic structure responds to local, national and international pressures. By forecasting the most likely industrial drivers, tying this in with demographic trends and knowledge from sectoral experts, it is possible to generate a view of the most likely future scenario for (in this case) 2015, based on currently available knowledge. Of course, there is no crystal ball and it is impossible to predict random events; these projections must be seen as indicative. They are ’if nothing alters’ projections but the reality is that nothing stays the same! As a result of this the margins of error must be seen as increasing the further we move from the base year.

This section examines the sources of increasing pressure on water use in the absence of constraints from the implementation of the Water Framework Directive. In reality of course users will be continuing in their efforts to reduce the use of raw materials including water, and pressure will be brought to bear on existing and new water uses. The growth and structural change of the economy to 2015 might suggest the changes illustrated in the table but these are not predictions of what will actually happen. If we were to predict the actual level of water use many sectors would have much lower rates of growth of use, stable levels of use and in some cases declines in water use.

What the table is intended to illustrate is the source of future pressures. It is important to understand not just how water use has occurred in the past or where water use is occurring at the present but where pressures for access to water might occur in the future. Understanding something about the sources of pressure for the future allows thought to be applied to how potential problems might be overcome before they become insurmountable. At the moment there has been no attempt to separate out these effects on a regional basis, or to relate these increases in pressure to specific water bodies. This will be explored in the coming years.

This section is based upon an R&D report on the dynamics of water use which is available on the SEPA website⁵⁹ and therefore, is for Scotland as a whole. This information has been used in conjuction with information from the report on the Economic Importance and Dynamics of Use report prepared for Defra⁶⁰. Where additional information is available for the Solway Tweed river basin district, this has been included.

This section concentrates on significant water users in terms of volume. Table 27 below provides an overview of how water use could change by 2015.

Table 27: Summary of the predicted changes in water use for selected large volume users

Note: This table covers the geographical area of Scotland.
m³/yr = cubic metres per year
* It is the considered opinion of the Economic Advisory Stakeholder Group (EASG) that this figure is overly optimistic.

The most significant user in Scotland in volume terms is the electricity generation sector, which is expected to increase its demand for water by 23% over the 11 year period. (The level of water use by this sector for the Solway Tweed river basin district is uncertain). Hydro power sector experts, however, cast doubt on this assumption and it is worth restating that these figures represent the views of the consultant, based on their knowledge at the time of writing. Despite considerable uncertainty regarding the likely electricity mix in 2015; due in part to the lack of any clear decision as to how to fill the gap created by the decommissioning of the ageing power stations at Cockenzie, Longannet and Chapelcross; table 28 shows the assumed likely mix of generating capacity.

Table 28 Predicted energy mix in Scotland in 2015

The assumptions⁶¹ underlying these projections are examined in the Dynamics of Water Use report

The next most significant user of water is fish farming/aquaculture, which is mostly direct abstraction. This sector is expected to increase its water usage by 12% in the period to 2015. Figure 10 shows the projected growth of gross value added (output) in the sector and the resultant increase in water demand.

Figure 10 Forecast gross value added and water demand for fish farming

However, forecasts undertaken by Experian suggest that GVA for fish farming will decline slightly in Solway Tweed over this period (see Annex 2). If a similar relationship is evident between fish farming output and water use in Solway Tweed, then this would suggest that water demand is not likely to increase in Solway Tweed.

Household demand is also a highly significant use which is expected to increase by 2.4%. The population is forecast to continue its slow decline; however the number of households is set to increase as recent demographic trends predict more single parent families and smaller household sizes. This is true for both Scotland as a whole and the Solway Tweed river basin district. Technological improvements in the efficiency of many white goods, although significant, fail to offset this trend. This increase in water usage is depicted in figure 11 over the page.

Figure 11: Forecast total and average per capita water demand 2001 to 2015

Agriculture is the only large sector that is forecast to decrease its use of water. Demand is expected to fall by 12% over the period as a result of reforms made to agricultural support mechanisms within the Common Agricultural Policy (CAP), associated intervention price adjustments and world price expectations. For the purpose of this analysis, the models used to forecast future agricultural land use (livestock and cropping numbers) were calibrated to reflect the following policy and market scenario⁶²:

• A fully decoupled Single Farm Payment (SFP) system replacing the Arable Area Payment, Suckler Cow Premium, Beef Special Premium, Slaughter Premium and Sheep Annual Premium Schemes;

• A SFP based on historic average claims during a 2000-2002 reference period;

• Intervention price reductions by 2008 for beef, cereals and milk as laid out by the European Commission in CAP reforms texts;

• Average world price forecasts to 2010 provided by OECD⁶³ and FAPRI⁶⁴ for wheat, barley, beef, milk and sheepmeat.

The Experian forecasts for the Solway Tweed river basin district also suggest a decline in agricultural output from Solway Tweed over the period to 2015. This is broadly based, with declines in output from cropping and livestock (see Annex 2 for more information).

The effects of these assumptions can be seen in Table 29 below. Figures are for Scotland as a whole.

Table 29: Basic water demand result for the Agriculture sector

(Note: Pigs and Poultry numbers assumed unchanged)
* m³/yr= cubic metres per year

An in-depth agriculture business as usual study for the Water Framework Directive was undertaken by Cambridge University. The full report can be found at: www.environment-agency.gov.uk/economics. The study provides quantitative percentage changes of key agricultural activities to 2015 at a national level and at a regional level for Government Office Regions in England and for Wales (see Tables 16-18 ibid.). The report used a top down approach, essentially looking at overall changes in England and Wales and adjusting these based on knowledge of the region and expert opinion to reflect regional changes. The Solway Tweed RBD is within the North West and North East Government Office Regions. The key projected trends for major commodities in these areas:

• removal of set-aside brings land into arable production;

• small increase in cereal production (particularly wheat and maize) due to set aside changes;

• continued decline of dairy herd as yields increase;

• decline in beef and sheep herds; and

• a continued decline in horticultural crops (especially potatoes).

Overall a small fall in overall agricultural area is predicted. However, this may hide potentially significant changes in the structure and intensification of the industry and how businesses are managed. This may have impacts on water quality. For instance, more intensive cropping through greater use of fertilisers may impact on diffuse pollution.

Estimates have been produced for various industrial uses (specifically electrical and engineering, fibres and food & drink) but it is necessary to be cautious about the data underlying these estimates and it is not possible to spell out a definitive ranking. An important point with all industrial processes is the distinction in terms of public supply and that from private abstraction. The latter raises questions about the location-specific impacts and failure to meet quality targets if abstraction demand increases. Although water use in agriculture is forecast to decline by an eighth there will be significant spatial differences and water demand may increase in certain parts.

59 http://www.sepa.org.uk/wfd/stake/eas

60 http://www.defra.gov.uk/environment/water/wfd/economics/index.htm

61 These assumptions should in no way be taken to represent SEPA’s desired, or preferred situation.

62 These assumptions should in no way be taken to represent SEPA’s desired, or preferred situation.

63 Organisation for Economic Co-operation and Development

64 Food and Agricultural Policy Research Institute.