“The argument against river transfers is that it involves a major interference with the existing ecology of these rivers, introducing water which is chemically different, almost certainly at a different temperature and potentially carrying foreign river life as well as material in suspension.”
Professor J. Uff Q.C.1
On 26 April 1996 Yorkshire Water Services (YWS), in response to the water shortage in Yorkshire, announced its decision to develop a £50 million water transfer scheme from the River Tees to the River Ouse2.
Inter-river transfers are used to redistribute water from areas of surplus supply to those where there is a shortage of water. Globally, there is growing interest in using this approach to meet water demands.3 However, such projects may cause serious environmental and social impacts.
These impacts will vary depending on whether transfers are used as a continuous supply of extra water or intermittently.4 Continuous use may cause long term changes in average hydrological conditions. For example, the Orange/Fish inter- basin transfer in South Africa transformed the great Fish River from a series of unconnected pools to a permanently flowing river. 5 Intermittent transfers, in contrast, will cause sudden disturbances whose impacts will vary depending on frequency and duration of transfer.
Yorkshire Water's scheme threatens to:
YWS proposed two options for water transfer:
Option A Direct transmission through a raw water pipeline from the River Tees to Moor Monkton on the Ouse.
Option B River transfer from the River Tees to the Ouse using a short length of pipeline to transfer water from the River Tees to, either the River Swale (Option B1) or to the River Wiske (Option B2) and then to the Ouse.
With initial plans to extract 200 tcmdi of water, they hope to develop the capability to transfer 300 tcmd in the future.6 Put in context, this is roughly equivalent to a daily supply of 2- 3000 road tankers of the type YWS used to transport water during the 1995 drought.ii
As water is removed from the Tees it will be replaced by headwater reservoirs and possibly by transfers from Kielder Water on the River Tyne. The transferred water to supply Yorkshire may therefore originate in the Tyne. The scheme is intended to be operational whenever there is insufficient water available from Yorkshire Water's existing sources.
The purpose of this paper is to outline the potential ecological impacts of the water transfer scheme. Section 1 provides a review of the ecological impacts of inter-basin transfers. A brief history of the Kielder Water scheme is given in section 2 while the main body of the briefing examines the scoping study of the Tees transfer scheme, carried out for Yorkshire Water Services (section 3). Opposition to the scheme is discussed in section 4 and recommendations provided in section 5.
While little is known about the specific ecological impacts of inter-river transfer, four particular impact areas can be recognised. 7
One of the main objections to transfers is the possibility for transmission of non-native species and disease into the receiving river. This risk arises because water from biogeographically distinct areas is mixed, water which will vary in quality and support different flora and fauna. Non- native species may quickly spread through a river system and gradually replace related native species. Transfer of insects, plant seed, fish species, pheromones, fish diseases and parasites is possible.
Screens can be used to reduce transfer of animals but doubt exists as to their effectiveness. Gibbins8 reports large numbers of animals being transported through the Tyne-Tees pipeline and screens will not prevent the transfer of microorganisms.
In any water transfer there will be impacts on the hydrology of both donor and receiving rivers and donor reservoirs. Changes in flow regimes cause shifts in species diversity, population density and life cycle patterns in insects and fish.9 Boon (1993)10 suggests that the feeding nets of filter feeding insects may be destroyed in rapidly flowing rivers. Unable to catch food they are displaced by predatory insects which are more able to withstand unstable, high flows. High current speeds also wash fish eggs and newly hatched fish fry downstream.
Changes in volume and rate of river flow will affect sediment transport in rivers and channel morphology. Increased flows encourage bank and bed erosion and alteration to habitat.
Sediments from eroded river beds and banks are deposited downstream as flow rate drops. Gravel banks that are habitats for insects or spawning areas for fish may be covered with these deposits and lost as feeding and breeding grounds. Other habitats may be permanently or temporarily lost as a result of increased water levels or landtake. Vegetation that is more frequently submerged as a result of higher water levels may no longer be available to other species as food or habitat.
Transfer of water between rivers can result in:
For example, fish may be affected if colder water is transferred to a river from a reservoir or by pipeline. Both spawning activity and growth rates may be suppressed. A study of the impacts of reservoir water released into the Dee estuary, Wales, showed that temperature differences could be related to changes in distribution of fish species.11 Roach, which had been the dominant species, were replaced by dace. These temperature effects can persist for tens of kilometres. In the Dee estuary the effects of reservoir water, released at a different temperature to river water, was observed to affect fish distribution at a distance of 50km.12 Temperature changes also affect flow characteristics of rivers13 and this too will alter habitats.
The YWS scoping report noted that the phosphate, nitrite and chloride levels in the Tees are up to nine times greater than the Swale. Such elevated nutrient levels could stimulate algal overgrowth on the river surface. When the algae die and decompose oxygen is used up from the water. This process known as eutrophication can result in losses of insect and fish populations.14 Deoxygenation of reservoir releases15 and transfer water held in pipes also occurs. Additionally, soluble metals may precipitate on mixing with more alkaline waters.
Broader environmental impacts include the effects on views and areas of scenic importance of the construction of pumping stations and access roads. Additionally, there will be disturbances associated with pipeline construction and new pump stations will contribute to noise impacts.
Kielder water, Britain's biggest artificial water store, lies in Northumberland, within 5 km of the Scottish border. Completed in 1982, it transfers water form the River Tyne catchment southwards to the rivers Wear and Tees.16 Kielder was built in response to pressure from industries in the northeast, such as British Steel and ICI, who predicted big increases in water demand.17 But as heavy industry declined so too did the demand for water, winning Kielder the reputation of being Europe's biggest boating lake. Only twice in its history has Kielder been used to transfer water to the Tees, first in 1983 and then 1989.
This is not the first time that a giant water transfer scheme from Kielder has been proposed. In 1991 there were plans to use the reservoir to supply the Chapelcross nuclear site near Lockerbie in Scotland, operated by British Nuclear Fuels (BNFL).18 These plans never went ahead as they were considered commercially non-viable..19
In the UK Environmental Statements (ESs) are required for certain projects which may have a significant impact on the environment.20 Statutory requirements to prepare ESs were introduced in the UK in mid-1988 with the implementation of the 1985 EC Directive on environmental assessment of major projects (85/337/EEC). However, pipeline or inter- catchment transfers are not currently included in the categories for which an Environmental Assessment (EA) is mandatory. Nevertheless, the Environment Agency has made it clear that a full EA for the Tees Transfer proposal will be expected 21
In anticipation of the full assessment, Yorkshire Water Services commissioned a scoping study of the likely environmental impacts. This was published in June 1996. The report, carried out by consultants Mott MacDonalds, noted that there could be effects on hydrology, water quality, fisheries, ecology, landuse and landscape, archaeological and cultural heritage, noise, air quality and traffic. Specific impacts on the rivers involved are outlined below.
However, even before the scoping study was published the decision had been taken to build a 13km pipeline from the Tees to the Wiske because of concerns about continuing water shortage in Yorkshire.22 Tees water will travel down the Wiske to the Swale and on to the Ure, then Ouse. From here it will be pumped to a treatment works near York. Construction of the pipeline did not require an environmental assessment but in order to use it YWS will have to get a Drought Order from the Secretary of State for the Environment. The inquiry into Yorkshire Water held early in 1996, and headed by Professor John Uff, advised that the Tees-Wiske link should not be seen as a “permanent solution”.
Reservoirs and rivers that will be affected by the transfer scheme include the Kielder and Cow Green reservoirs and
the Tyne, Tees, Swale, Wiske, Ure and Ouse rivers.
The scoping study predicted little impact on either Kielder or Cow Green reservoirs beyond a lowering of water level, particularly in summer. Such a fall may bring about a reduction in water quality, impact the visual amenity of the sites and disrupt recreational use.
The scoping study reported the presence of a protected invertebrate species in the area.iv Otters are also found throughout the catchment and along the stretch that will be influenced by abstraction to the Tees.
Here, the key impact of increased releases from Kielder will be the production of higher summer flows. Additionally, colder waters released from the reservoir into the upper reaches of the Tyne may affect fish populations, notably dace. This would be a particular problem if the scheme is operated between March and May. Coarse fish in the Tyne are at the limit of their natural range and so are sensitive to temperature changes. 23 Consequently, a reduction in the water temperature will affect fish spawning success and growth rates.
The Tyne is also an important salmon and sea trout fishery. High current speeds resulting from increased flows may cause redistribution of salmon. Furthermore, fish may be drawn into the intake at Riding Mill during pumping operations and killed.
Described as a fine quality river habitat, the Tees flows through upper Teesdale National Nature Reserve and the Shipley and Great Wood SSSI. Several scarce species of caddisflies, mayflies and stoneflies have been recorded in its upper reaches. Other regionally and locally scarce insects have been recorded.
The scoping report noted that there is not suitable data for assessing actual and potential impacts of transferring water from the Tyne catchment to the Tees catchment. Clearly, water transfer will lead to higher flows than at present, possible changes in the level of the water table, and changes in water quality. The transfer of soft acidic upland water from the Tyne to the harder neutral or slightly alkaline Tees may affect river species. For example, the native white- clawed crayfish Austropotamobius pallipes, prefers hard, alkaline water24. This species, which provides food for fish and otters, is protected under the Wildlife and Countryside Act 1981.
There are likely to be effect on fisheries, insects, birds and plants. Of particular concern is the potential for introduction of fish disease. Of two trout farms on the River Tyne, one is known to harbour bacterial kidney disease (BKD). In contrast, both trout farms on the Tees are apparently clear of disease. Additionally, the secondary bacterial infection Aeromonas sobria has been identified in salmon from the Tyne estuary but not in Tees salmon.
Temperature changes in the Tees, caused by the addition of pipeline water, may affect fish spawning success or growth rates. If the transfer were to operate from December to January such changes could affect the spawning activity and hatching of salmon and trout. Greater summer flows may cause a redistribution of salmon and there may be fish kills at intake points.
Introduction of polluted water from the Tyne could cause fish mortalities in the Tees and loss of insects and plants resulting in a potential loss of bird feeding areas.
Transfers could introduce new plant species and insects to the Tees from the Tyne. In particular, the American signal crayfish Pacifastacus leniusculus, a non-native species, could be introduced. This is a vigorous, invasive species that out -competes the native white-clawed crayfish. It also carries a fungal plague Aphanomyces astaci which is spread by millions of spores and is fatal to native crayfish. The ecological implications of crayfish plague are considered so serious that under the Wildlife and Countryside Act 1981 it was made illegal to introduce signal crayfish to the wild .
Rapid changes in water depth and velocity may adversely affect insects and species that breed on vegetation. Nesting sites of birds that breed on shingle spits, common sandpiper and little ringed plover for example, could be washed out.
Channel works or the construction of new facilities on the River Tees could lead to loss of agricultural land and disruption of agricultural activity.
The upper reaches of the Swale flow through a succession of sites of local Nature Conservation Interest and non-statutory sites of nature conservation interest. Further down stream Brompton-on-Swale Lake SSSI, noted for its wildfowl, receives groundwater from the river. Changes in river quality may therefore affect the lake. The Swale, like the Tees, supports scarce insects including a nationally rare water beetle, several regionally scarce insects and twenty three species of local importance. Otters are present, though in small numbers.
On the Swale increased water levels in the river could raise the level of the watertable and increase the risk of flooding to agricultural land, properties and industries. Summer flows may actually be doubled when the transfer scheme is operating. Increased water levels and flow rates may result in drowning out of gravel spits and some riffles. These are important habitats for fish, insects and birds. Nest sites of common sand pipers and little ringed plover may be washed out.
The Swale may experience slight softening of overall water quality which could affect those species that prefer hard water (base-rich) conditions. Water confined in the Tees- Swale pipeline when it is not operating may be subject to more temperature variation than in the Tyne-Tees tunnel. A short-term influx of water of different temperature could affect insects and fish spawning successes and fry growth.
As in the Tees there is a risk of introduction of non-native crayfish and crayfish plague. Additionally there is the potential for invasion of giant hogweed.
Introduction of polluted water from the pipeline could cause loss of fish, insects and plants and potential loss of bird feeding sites. As transfer times are only a few hours, a pollution incident at night might not be detected in the Tees before it has reached the Swale. Water left standing in pipelines may become deoxygenated causing fish and invertebrate mortalities. Additionally, pipelines may need to be dosed with chlorine to clear colonies of Zebra mussel Dreissena polymorpha which can block pipes. Toxic by- products at the pipe outfall may kill pollution sensitive species, such as locally important mayflies and stoneflies.
Channel works or increased erosion of river cliffs resulting from faster flows, could affect the Swale's breeding kingfisher and sandmartin populations.
Intensive farming, drainage and river management has produced an impoverished habitat. Nevertheless there are records of two nationally notable, two regionally scarce and ten local invertebrate species. Those species that prefer slow flowing rivers may be lost.
River transfer to the Wiske would force 1000% more water through its narrow channel in summer. At this time of year an addition of 2.32 m3/s to the Wiske would cause its depth to increase by about half a metre. As the water table rises, land drains may lose their effectiveness. This will bring increased risk of flooding of properties and land, disruption of agricultural activity and represent a potential hazard to river users and grazing cattle. Homes in the village of Danby on the Wiske, located in the flood plain, may be at risk from flooding. The frequency of flooding may increase in those areas where it already occurs, for example, Yafforth, South Otterington and Kirby Wiske.
Higher and more rapid flows could lead to loss of the Nationally notable alder fly Sialis nigripes. Plants like water forget-me-not will be drowned out if the channel fills to bank level. To cope with the increased flows the channel would need widening and dredging. Weed clearance would also be necessary and this could affect fish and birds.
Again there is a risk of introduction of fish disease. While discharge of cleaner Tees water could improve water quality in the River Wiske, English Nature have warned against using the transfer as a method for improving water quality. This could be achieved by upgrading the sewage treatment works.
The introduction of the softer Tees water will change the mineral composition of flows in the Wiske. In conditions of low flow there may be changes in water quality from hard to moderately soft or slightly hard.
At high flows water levels and velocities will rise and there may be changes in water quality, all of which may affect insects, fish species, plants and nesting birds. The Ouse is used as a coarse fishery and there are particular concerns that fish could be drawn into the intake at Moor Monkton. Additionally, some engineering work would be required here to cope with increased flows.
Records exist for two nationally notable, six regionally scarce and twenty three local species. Most of the scarce species prefer slow flowing river conditions.
As noted in the Introduction there are two options under discussion. The potential impacts of direct river transfer have been discussed above. Transfer by pipeline from the Tees to the Ouse will also have environmental impacts. Both options will require additional works.
Construction of pipelines will involve land take and production of
spoil which has to be disposed of. Construction activities could cause
short-term disruption to farming activities with potential for damage
to drainage systems and fences. During construction of pipelines and
pumping stations vehicles used create pollution, noise and disruption
to other road users. Longer term impacts include soil compaction, topsoil
loss and localised noise from the operation of new pumping stations.
A number of SSSIs, Sites of Local Nature Conservation Interest and non-statutory sites of nature conservation lie near the pipeline corridor. Upper Dunsworth Carr SSSI is closest to the pipeline corridor but the pipe can be kept 1km away from this. Additionally, the pipe could be aligned to avoid all non-statutory sites. While it is possible to lay the pipeline away from woods, ponds and other sensitive habitats it is not possible to avoid hedges. Consequently there could be impacts on hedgerow birds, for example, yellow hammer. Moreover, there would be loss of other non- designated habitats such as grassland, wetland and woodland.
“There are major environmental and ecological concerns about the rivers of Yorkshire and it would be a tragedy if a reliable public water system were to be achieved only at their expense”
Professor J. Uff Q.C.25
While environmental assessments may be carried out for inter-basin transfers there is concern that ecological consequences are not adequately assessed.26 Moreover there is insufficient understanding of the ecological interactions of river systems to make a realistic assessment. Surveys tend not to be carried out to species level yet this is considered critical information for impact studies.27
There are a number of references in the scoping report to a lack of data to enable environmental assessment. For example, while mass balance calculations do not indicate significant changes in water quality it is recognised that data is not available for conditions under which transfer would take place.
There is little doubt that the Tees transfer scheme is being pushed through too quickly before the environmental impacts have been assessed. Meador28 proposed that before a transfer scheme is developed there should be a minimum of three year pre-operational baseline studies, followed by a one year period to evaluate the transfer, making a total of four year's assessment before operations begin. Three years post-operation studies should then follow.
Compare this then to Yorkshire Water's plans, hastily developed in response to the 1995 drought, and already being pushed through by on-going construction of the pipeline from the Tees to the Wiske. The company plans to have the project complete by the autumn to provide emergency back-up if insufficient rain falls this summer. 29 Currently YWS claim that use of the pipeline is a remote possibility but do intend to apply for a Drought Order if necessary.30
The Environment Agency has too few powers to prevent the scheme but it does carry influence with Yorkshire Water and the Secretary of State, who will make the final decision on whether the pipeline will be used. As protectors of the environment, it is the Agency's duty to make it clear that the scheme threatens too much damage and should not be used.
There seems to be little support for the river transfer scheme outside of YWS. Professor Uff stated that “it would not be possible to reduce the risk of serious environmental damage to these rivers to an acceptable level”. Local authorities in Yorkshire, such as Sheffield and York City Councils, have voiced their concern. English Nature have identified potential impacts to the Environment Agency and the consultants, Mott Macdonald. Of the two options they will recommend transfer by pipeline (Option A) not by river.31
The Environment Agency requires a full environmental assessment to be carried out over two years and their preferred option is also likely to be transfer by pipeline.32 It remains to be seen whether they will oppose use of the Tees- Wiske pipeline this summer.
Friends of the Earth believes the transfer scheme is unnecessary and has investigated alternatives to meeting people's water needs.33
1. Uff, J. (1996). Water Supply in Yorkshire. Report of the Independent
Commission of Inquiry. London p113.
2. Uff, J. (1996). op cit.
3. Davies B.R. Thoms M. and Meador M. (1992). An assessment of the
ecological impacts of inter-basin transfers, and their threats to river
basin integrity and conservation. Aquatic conservation - marine
and freshwater ecosystems 2 (4) pp 325-349.
4. Gibbins C.N. (1996). The impact of water transfers on the macroinvertebrate
fauna of the River Wear. Unpublished PhD thesis, University of Northumbria,
Newcastle upon Tyne, UK.
5. O' Keefe J.H. and de Moor F.C. (1988). Changes in the physico-chemistry
and benthic invertebrates of the Great Fish river, South Africa, following
an interbasin transfer of water. Regulated Rivers: Research and
Management 2 (39-55).
6. Yorkshire Water Services (1996). Tees Transfer Environmental
Scoping Study. Main Report. Yorkshire Water Services.
7. Meador M.R. (1992). Inter-basin water transfer: ecological concerns.
Fisheries 17 (2), pp17-22.
8. Gibbins C.N. (1996).
9. O' Keefe J.H. and de Moor F.C. (1988). op cit.
10. Boon P.J. (1993). Distribution, abundance and development of
trichoptera larvae in the River North Tyne following the commencement
of hydroelectric power generation. Regulated Rivers: Research &
Management 8, 211-224.
11. Hodgson, B. (1996). Pers. comm. Environment Agency.
12. O'Hara, K. (1996). Pers. comm.
13. Krasovskaia I. (1996). Sensitivity of the stability of river
flow regimes to small fluctuations in temperature. Journal des Sciences
Hydrologiques 41 (2), pp251-264.
14. Odum E.P. (1975). Ecology: The Link between the Natural and
the Social Sciences. Holt, Rinehart and Winston, 1975.
15. Barillier A. Garnier J. and Coste M (1993). Experimental reservoir
water release: impact on the water quality on a river 60km downstream
(Upper Seine River), France. Water Resources 27 (4), pp635-643.
16. Gibbins C.N. Soulsby C. and Merrix R.F. (1994). The impact of
inter-basin transfers on invertebrate communites of the River Wear.
In: Kirkby C. and White W.R. (Eds.) Integrated River Basin Development.
Wiley and Sons, Chichester, pp165-177.
17. Pearce F. (1991). Pipe dreams to quench Britain's thirst:
thousands of hectares of fields, meadows and marsh are threatened by
plans for new reservoirs in southern England. Environmentalists say
the plans are full of holes. New Scientist 132 (1795), p17.
18. New Scientist (1991). Will English water quench Scottish reactors'
thirst? New Scientist 131 (1787) p16.
19. Hall D. (1996). Pers. comm. Tyne Anglers Association.
20. Environment Agency (1996). Environment Assessment: Scoping Handbook
for Projects. Report of the Environment Agency. HMSO, London.
21. Chalk E. (1996). Pers. comm. Environment Agency.
22. Walden S. (1996). Pers. comm. Yorkshire Water.
23. Hall D. (1996). Pers. comm. Tyne Anglers Association.
24. Marren P. (1986). The lethal harvest of crayfish plague.
New Scientist 30 January.
25. Uff, J. (1996). op cit.p110.
26. Davies B.R. Thoms, M. and Meador M. (1992). op cit.
27. Gibbins C.N. (1996). op cit.
28. Meador (1992). op cit.
29. The Guardian (1996). Water scheme 'cheap option', June 1st.
30. Walden S. (1996). Pers. comm. Yorkshire Water.
31. Barratt J. (1996). Pers. comm. English Nature.
32. Chalk E. (1996). Pers. comm. Environment Agency.
33. FOE (1996). Alternatives to the Kielder Transfer Scheme.
Frances MacGuire
July 1996
Published by Friends of the Earth Ltd
© Friends of the Earth Ltd
Friends of the Earth England, Wales and Northern Ireland
26-28 Underwood Street
London N1 7JQ
Telephone (0171) 490 1555,
Email: info@foe.co.uk
Printed on 100% recycled paper
return to text
i tcmd = thousand cubic metres
per day
return to text
ii 9-10 tankers needed to transport
1 tcmd (Uff,
1996).
return to text
iii BOD - biological oxygen
demand, COD -
chemical oxygen demand, DO - dissolved oxygen
return to text
ivNo identification was given
for this species in the scoping report.
Contact details:
Friends of the Earth
26-28 Underwood St.
LONDON
N1 7JQ
Tel: 020 7490 1555
Fax: 020 7490 0881
Email: info@foe.co.uk
Website: www.foe.co.uk
July 1996
Frances MacGuire
Last modified: December 2001
