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An economic analysis of water use in the Scotland river basin district |
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2.3 Economic sectors and their water use This section provides an overview of the ways in which different sectors currently make use of water in Scotland. In addition to this overview, some water users have provided their own sectoral analysis, each of which have been reproduced (unedited) in the appendices to this document and are also available through the SEPA website12. To date analysis has been received from the following groups:
The availability of a separate sector report is indicated by an asterisk in the following sections.
There is a significant agricultural sector in Scotland, employing 28,645 full-time, 35,709 part-time and nearly 4,000 casual and seasonal workers. Agriculture and forestry account for almost 1.50% of gross value added to the Scottish economy. Water is essential to the agricultural sector for irrigation, drinking water for livestock and cleaning. Most agricultural water needs are met by precipitation, however, where irrigation is necessary, the benefits are substantial. Water also carries excess chemicals away from the land and transports them to other water bodies. Agriculture and forestry is responsible for under two-thirds of all diffuse pollution pressures.
Scotland’s coastal waters, lochs and rivers are used for a large amount of commercial fish and shellfish farming which depend on unpolluted water. In 2002, almost 150,000 tonnes of salmon and some 3,200 tonnes of shellfish were farmed in Scotland. Many fish farms are part of large corporations, however, most shellfish producers are small enterprises employing approximately 350 people collectively, in rural areas.
Mining and quarrying accounts for 1.1% of employment and 2.13% of the gross value added to the Scottish economy, with the majority of this value attributable to the mining of energy producing materials. The nature of coal exploitation has changed significantly in recent years and deep mined coal is no longer produced in Scotland. Open cast coal mining* is, however, a significant contributor to the Scottish economy, producing over 7 million tons of coal per annum. Water use in the mining sector consists of diverting groundwater and drainage with subsequent consented discharges from settlement tanks.
In addition to the minerals produced, Scotland acts as a focus for the production of oil and gas. None of the oil and gas fields are within three nautical miles of the shore and are therefore not included in the production statistics above or the scope of this assessment. However, the production of oil and gas is significant for the Scottish economy, and there are oil terminals at Flotta, Nigg, Sullom Voe, Grangemouth, Dalmeny and Cruden Bay, and a gas terminal at St. Fergus.
Overall, this sector contributes 2.56% to the Scottish economy (using gross value added), although within this figure, the most significant contribution is made by the manufacture of chemicals (1.66% of gross value added).
There is a significant amount of mining for oil and gas off the North Sea coast. The refining takes place at two locations in Scotland: oil refining at Grangemouth and specialist lubricant and bitumen refining at Dundee. These account for only 0.21% of the gross value added to the Scottish economy. Oil refining and fuel processing use some mains supplied water (estimated at 1,350 m3/day for large users13, which is likely to cover all use in such a concentrated sector) and also abstracted fresh water; estimated at 15,000 m3/day14.
Food processing in Scotland is a diverse industry, although the main economic contribution from the sector is in meat and fish production. There is a notable lack of information on the nature, distribution and characteristics of the sector, and this gap is something that will be addressed in the future. The volume of water abstracted by organisations in the food processing sector was estimated as part of the study of abstraction in Scotland15. This study estimated the total mean use of water as 8,000 m3 for fish processing, 49,000m3 for vegetable processing, 63,000 m3 for meat processing and 117,000 m3 for dairy processing. Of these, direct abstraction was most common for vegetable processors, with a mean of 45,000 m3, with limited abstraction in the other sectors.
Scotland is noted for its production of Scotch whisky*, and the sector is important both economically and culturally. There are just over one hundred distilleries in Scotland, spread in particular across the Highlands, and concentrated along the River Spey. Around 41,000 jobs depend on the production of whisky, with just over 9,500 employed in production itself and a further 20,000 jobs in businesses supplying goods and services. Whisky production also supports Scottish agriculture, and uses approximately 390,000 tonnes of barley and 486,000 tonnes of other cereals each year. The sector also generates over £800 million of income (principally in wages and salaries). Two types of whisky are produced: malt whisky and grain whisky. Malt whisky is made from malted barley, water and yeast and is sold in small quantities as single malts but most production goes to be blended, where it is mixed with grain whisky. Grain whisky is made on a larger scale and uses a different process using wheat or maize with smaller quantities of malted barley. The precise volume of water used in whisky production is difficult to calculate and different sources provide differing numbers. Details of this discussion are available in the Scotland and Northern Ireland Forum For Environmental Research (SNIFFER) Economics of Water Use report16. Best estimates show that malt distillers abstract 76.49 million m3 each year. The technical definition of water use for the whisky sector would include all water diverted for the purpose, however the sector’s own definition would be merely the water abstracted from that diversion. As the pure alcohol produced by the distillery is diluted with water to produce the final product, account must be taken of this water use as well. The SNIFFER report referred to earlier has the details of how this was estimated; however, based on an estimated 856 million litres of whisky sold in 2002, the direct water component equated to 513,000 m3.
Mineral water The Scottish mineral water companies supply approximately 35% of the UK consumption of bottled water, which was 1.8 billion litres in 2002. The production of mineral water in Scotland, as elsewhere, requires brands to be linked to specific springs. However, in some places more than one brand is linked to a single spring, most notably at Lennoxtown (Burnbrae Spring, Caledonian Spring, Campsie Spring, Glenburn Spring, Glencairn, Heather Spring, Lowland Glen, Scottish Mineral Water and Strathglen Spring). In such cases, the total abstraction would include water that is diverted and is more significant than indicated by the economic importance of individual producers. Based on satisfying 35% of UK consumption, Scottish companies produced approximately 630 million litres (630 million m3) in 2002. More than half of this comes from the main producer of bottled water (Highland Spring) who bottled approximately 320 million m3 17. This would be consistent with the estimated sector abstraction of 687 million m3, since this larger figure would include process water and excess water discharged immediately.
Textiles and leather is a relatively small economic sector in Scotland, accounting for only 0.87% of gross value added. However, they are significant in terms of their historic contribution to Scotland and also in terms of water use. The tannery sector is an intensive water user; with approximately 20 m3 of water required to process 1 tonne of raw hide into 300 kg of saleable leather. Both private and public water supplies are used. Due to the organic content of the tannery effluent (which requires treatment before discharge) and the urban location of the tanneries, primary effluent treatment is typically provided before discharge to mains sewers.
Wood, paper and pulp employs 3,380 people to produce approximately 1.25 million tones of paper per year (Confederation of Paper Industries 2004), accounting for 2.31% of gross value added in Scotland (National Statistics, 2003). Although the manufacture of paper is part of a chain from forestry through to manufacture, the industry in Scotland is focused around the manufacture of paper, and most mills import treated woodpulp for raw material (only one, Caledonian Paper, produces its own pulp). There are twelve paper mills in Scotland, concentrated in the Forth/Clyde valley and around Aberdeen where they were historically situated in proximity to suppliers and markets in towns as well as close to water sources for production processes. The industry, which specialises in high quality graphics paper, is very competitive. Five mills have closed since 2000 in response to changes in international economic conditions, domestic prices and regulation.
The chemicals sector is a significant water user in Scotland, both in terms of volume used and the resultant discharge. The largest company in the sector is operated by BP Chemicals at Grangemouth, although there are also a large number of small chemical companies. It is an extremely varied sector producing a wide range of different organic and inorganic chemical products. Processors may use large volumes of water for processing, generating steam for heating, cooling, and cleaning equipment and chemicals. Although there is reliance on mains water, sea water is often used for cooling and there is some abstraction in the sector in Scotland with grey water also used for cooling at some facilities. Water treatment may be necessary as a result of many of the processes involved in the manufacture of chemicals, from overflows of the storage tanks used for supplying the raw materials, through synthesis and product separation, to leakage from pipes during product storage. The types of pollutants from chemical production that may affect water bodies vary according to the type of chemical produced and are discussed in the background research18.
There are a number of other manufacturing sectors in operation in Scotland, contributing 9.78% of the gross value added to the Scottish economy. Within this, the contribution of the manufacture of electrical and optical equipment is by far the most significant, accounting for almost half of the total contribution.
These facilities are all located on the coast and are dependent on marine water to use in through flow systems for cooling. Although net abstraction is insignificant, the significant change to the water is through the increased temperature of discharge. Longannet and Cockenzie report an estimated use of river water of 1,587 million m3 and 643.4 million m3 respectively in 2002/3. British Energy and BNFL report any changes in radioactive content of the water close to nuclear facilities. The two major nuclear facilities are estimated to use approximately half a million m3 of water for cooling each year. In addition to water for cooling, fresh water supplied by Scottish Water is used to create steam to drive the turbines and for site use. Longannet and Cockenzie were supplied with 2.86 million m3 and 1.51 million m3 respectively in 2002/3. This is equivalent to 7,836 m3 and 4,154 m3 per day. Mains water use at the two nuclear facilities was 840,000 m3 at Hunterston B and 341,000 m3 at Torness for 2002/3, equivalent to 2,301 m3/day and 934 m3/day respectively. Future water uses in this sector may include wave and tidal power installations.
Hydropower schemes can be constructed on-line or off-line, depending on whether water is to be diverted from its original course. On-line schemes were popular some decades ago, but are no longer favoured, due to the impacts on migratory fish and other species and problems of siltation and larger substrate accumulation behind the structure. Off-line schemes divert the water and then return it back to the watercourse and this may have different problems, particularly due to the distance between abstraction and discharge. This may lead to low flows in a portion of the river, particularly during periods of when the river is naturally in low flow. Hydropower schemes can also use dams to create a high reservoir and increase the distance over which the water falls. The reservoir also stores water so that the flow can be regulated over periods of different rainfall and different electricity demand. Some schemes also use pumps from a low reservoir to return the water to the high reservoir, from where it can be reused during periods of high demand e.g at Cruachan. The power generated from hydroelectric schemes depends on the flow of water and the height over which the water is pressurised. Currently an estimated 3.355 billion m3 of water are stored in reservoirs serving Hydro schemes. Consultants estimate that around 10% of electricity generated in Scotland comes from hydropower. |
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