Water Abstraction from the River Itchen, Hampshire, United Kingdom



The River Itchen is a classic chalk river arising from the chalk aquifer of the Hampshire Downs in central southern England. It is world famous for its fly fishing for trout and Atlantic salmon and was where the techniques of dry fly fishing were first developed in the early 20th century. The river has been used for centuries as a source of power, to irrigate flood plain water meadows and as a source of drinking water. These various uses have had a range of effects on the river and its associated wetlands but despite these many changes it retains a rich biodiversity. This case considers predicted future impacts of abstraction (extraction) for public water supply. This could be an example of ‘imminent threat’ as defined in the Environmental Liability Directive (Article 2—‘sufficient likelihood that environmental damage will occur in the near future’). The removal of water from the river results in reduced water levels and most importantly, reduced flow velocity. This causes a range of effects on the river including increased temperature, reduced oxygen concentration and increased concentration of plant nutrients, particularly phosphate, and other contaminants. Previous investigations have shown that in naturally dry years water abstraction has the potential to cause damage to the populations of Atlantic salmon and the floating Ranunculus habitat of the river. This case study uses habitat and resource equivalency analyses to estimate the damage and select compensatory remediation. The economic value of Atlantic salmon is also presented.


Habitat equivalency analysis Resource equivalency analysis Value transfer Water abstraction Salmon Floating Ranunculus 


  1. Atkins. (2006). River Itchen SAC review of consents, water resources stage 4 project, site action plan: Appendix B—Development of a stage 4 target flow regime, Unpublished report to the Environment Agency.Google Scholar
  2. Baglinièrea, J.-L., Marchandb, F., & Vauclin, (2005). Inter-annual changes in recruitment of the Atlantic salmon (Salmo salar) population in the River Oir (Lower Normandy, France): Relationships with spawners and in-stream habitat. ICES Journal of Marine Science: Journal du Conseil, 62(4), 695–707.CrossRefGoogle Scholar
  3. Environment Agency. (2004). The State of England’s Chalk Rivers. A report by the UK Biodiversity Action Plan Steering Group for Chalk Rivers, Environment Agency and English Nature.Google Scholar
  4. Environment Agency. (2006). Salmon stock assessment report: Annual assessment of salmon stocks and fisheries in England and Wales, Bristol.Google Scholar
  5. Environment Agency. (2007). Results of electro-fishing surveys, Langford Lakes, 2003–2007, River Wyle, Avon Catchment, Unpublished data provided by the Environment Agency.Google Scholar
  6. Environment Agency and CEFAS. (2006). Annual assessment of salmon stocks and fisheries in England and Wales 2006. Report by Environment Agency, Centre for Environment, Fisheries & Aquaculture Science.Google Scholar
  7. European Commission. (2007). Guidance document on Article 6(4) of the ‘Habitats Directive’ 92/43/EEC, Brussels.Google Scholar
  8. Exley, K. P. (2003). The River Itchen macrophyte community, Unpublished report to the River Itchen Sustainability Study, November.Google Scholar
  9. Exley, K. P. (2004). Macroinvertebrate habitat and community status of the River Itchen, Unpublished report to the River Itchen Sustainability Study.Google Scholar
  10. Exley, K. P. (2006). River Itchen macroinvertebrate community relationship to river flow changes, Unpublished Report, Environment Agency.Google Scholar
  11. Extence, C. A. (1981). The effect of drought on benthic invertebrate communities in a lowland river. Hydrobiol, 83, 217–224.CrossRefGoogle Scholar
  12. Extence, C. A., Balbi, D. M., & Chadd, R. P. (1999). River flow indexing using British benthic macroinvertebrates: A framework for setting hydroecological objectives. Regulated Rivers: Research & Management, 15, 543–574.CrossRefGoogle Scholar
  13. Fewings, G. A. (2004). Estimation of the effect of river discharge management on the passage of Atlantic salmon (Salmo salar L.) through the lower reaches of the River Itchen in Hampshire, Unpublished report to the River Itchen Sustainability Study.Google Scholar
  14. Holmes, N. (2003). Concept designs for River Rehabilitation and enhanced Salmon Migration above Woodmill Pool, Unpublished report to the River Itchen Sustainability Study.Google Scholar
  15. Nijboer, R. C., Verdonschot, P. F. M., & Van Der Werf, D. C. (2005). The use of indicator taxa as representatives of communities in bioassessment. Freshwater Biology, 50, 1427–1440.CrossRefGoogle Scholar
  16. Radford, A. F., Hatcher, A., & Whitmarsh, D. (1991). An economic evaluation of salmon fisheries in Great Britain, a Research Report to the Ministry of Agriculture Fisheries and Food, Research Report 16, Centre for the Economics and Management of Aquatic Resources, University of Portsmouth.Google Scholar
  17. Radford, A. F., Riddington, G., & Tingley, D. (2001). Economic evaluation of inland fisheries: Economic evaluation of fishing rights, R&D Technical Report/Project Record W2-039/TR/1 (Module A), Report to the Environmental Agency for England and Wales, Bristol.Google Scholar
  18. Riley, W. D., Mason, C., Rowlatt, S. M., Maxwell, D., Campbell, S., & Hull, S., (1998). The efficacy of River channel modification in maintaining improvements in salmonid spawning gravels following cleaning: Final report. CEFAS—contract report CO224, 169.Google Scholar
  19. River Itchen Study Steering Group. (2004). River Itchen sustainability study, final technical report, by Halcrow Group Ltd, Wiltshire, England.Google Scholar
  20. Scott, A., & Beaumont, W. R. C. (1993). Improving the survival rates of Atlantic Salmon (Salmo salar L.) embryos in a chalk stream. Institute of Fisheries Management, Annual Study Course: Cardiff.Google Scholar
  21. Solomon, D. J. (2002). Dibden terminal inquiry—Proof of evidence of David Solomon Topic: Fisheries and Fish, 55.Google Scholar
  22. Solomon, D. J. (2004). Development of action profiles for salmon, River Itchen sustainability study technical Ref: E(AP)02, Report to the Environment Agency.Google Scholar

Copyright information

© Springer Science+Business Media B.V. 2018

Authors and Affiliations

  1. 1.Jonathan Cox AssociatesLymingtonUK
  2. 2.eftecLondonUK

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