Garcia de Jalon, SilvestreGonzalez del Tanago, Marta G.Alonso, CarlosGarcia de Jalon, Diego2017-05-152017-05-152017-04-24García de Jalón, S., González del Tánago, M., Alonso, C. et al. The environmental costs of water flow regulation: an innovative approach based on the ‘Polluter Pays’ principle. Water Resources Management, Vol.31. Issue 9, July 2017, pp. 2809-28220920-4741http://dx.doi.org/10.1007/s11269-017-1663-0http://dspace.lib.cranfield.ac.uk/handle/1826/11890The EU Water Framework Directive (WFD) explicitly requires the full cost recovery of water services, including the environmental costs incurred from the damage that water uses inflict on the environment. Although flow regulation by river damming is one of the most prominent human impact on fresh water ecosystems its environmental costs are not properly included in water pricing. This paper presents a novel approach to assessing the environmental costs of flow regulation based on the polluter-pays principle. The methodology includes three steps: (i) assessing the admissible range of regulated flow variability, derived from the natural flow regime variability, (ii) estimating the daily environmental impact of regulated flows according to deviations from the admissible range of flow variability, and (iii) calculating the environmental costs of flow regulation. The procedure is applied to four river case studies in Spain, UK and Norway. The advantages over other water cost valuation methods are discussed. The methodology enlarges the current recognition of environmental costs of water use and represents a practical management tool within the WFD context, encouraging transparency and stakeholder communication.enAttribution 4.0 International (CC BY 4.0) You are free to: Share — copy and redistribute the material in any medium or format, Adapt — remix, transform, and build upon the material for any purpose, even commercially. The licensor cannot revoke these freedoms as long as you follow the license terms. Under the following terms: Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use. Information: No additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.Environmental costsFlow regulationEnvironmental impactValuationWaterArticle