Water Exploitation Index WEI+ Current state of play

Transcription

1 Water Exploitation Index WEI+ Current state of play Maggie Kossida ETC/ICM

2 Background Within the CIS period, an updated mandate on WSD was approved, requesting to deliver a set of common water scarcity and drought indicators. One of the proposed indicators has been the Water Exploitation Index (WEI) Currently a Technical Working Group (TWG) is working within the Expert Group on Water Scarcity and Drought (EG WSD) to improve the existing WEI

3 Traditional Water Exploitation Index -WEI Total abstraction per Year/Long term renewable resource Cyprus Belgium Spain Italy Malta Turkey Germany Poland France Portugal Estonia Greece England/Wales Czech Republic Netherlands Lithuania FYR, of Macedonia Bulgaria Hungary Switzerland Austria Denmark Luxembourg Slovenia Romania Finland Ireland Sweden Slovakia Latvia Iceland Norway 0% 10% 20% 30% 40% 50% 60% 70% WEI-Latest Year Water exploitation index = Annual total water abstraction as percentage of available long-term freshwater resources late 1980ies -early1990ies (WEI-90) compared to latest year available ( ) (WEI-Latest Year) WEI-90

4 Water Exploitation Index -WEI+ A revision of the WEIhas been introduced with the purpose of better capturing the balance between natural renewable water resources and abstraction. A relevant fact sheet has been developed. The proposed WEI+ aims mainly at: disaggregating the spatial and temporal scale of implementation redefining the actual potential water to be exploited (i.e. availability), by incorporatingreturnsandenvironmental requirements dealing with methodological issues (formula, thresholds)

5 Spatial scale disaggregation WEI Slovakia at RDB level Data source: WISE-SoE WQ 2006 reported data. Comment: Due to the regional disaggregation, Hron RBD stress conditions are depicted and not leveraged out as when calculated at country level WEI France at RDB level Data source: WISE-SoE WQ reported data. Comment: Due to the regional disaggregation, we can see the water stress variability which is not depicted if WEI is calculated at country level

6 Temporal scale disaggregation Variability of water stress in Kapos - Hungary 350 Renewable Water Availability Total Abstraction LTAA ( ) LTAA ( August) Volume of water (mio m3) WEI+ 18% WEI+ 39% WEI+ 167% WEI+ 41% August August Period Kapos RB, Hungary Neglecting the seasonal variation and running calculations only at annual level can fail to depict important stress conditions thatmay occur over summer

7 Revising the definition of availability - Incorporating Returned Water and Water Requirement (i.e. Environmental Flows) parameters Water Requirements: The level of stress or relevant water scarcity in a catchment changes if we subtract an amount of water that is not actually available for abstraction since it needs to be left in the catchment to maintain its ecological status (in line with WFD) or other legal requirements (e.g. treaties in transboundary rivers) Returned Water refers to the volume of water that is returned and available for re-use in the catchments, which in the case of e.g. cooling water may be a significant volume

8 Revising the definition of availability - Incorporating Returned Water and Water Requirement (i.e. Environmental Flows) parameters WEI Estonia at RDB level Data source: WISE-SoE WQ 2006 reported data. Comment: East Estonia is using a lot of water for energy coolingpurposes, and since this is not accounted for in WEI as a return, it looks as extremely water stressed

9 WEI+ and the need for improved data/statistics Disaggregated the right spatial and temporal scale are essential River Basin District (WFD RBD), Subunit, NUTS, River Basin: all are reasonable scales Further breakdown of the WEI+ per source (surface water, groundwater) is beneficial in order to evaluate the degree of exploitation of each of these sources, but data are still weak in this extend Accuracy of the reported data (it essential that the reported data are strictly aligned to the definitions when we use them for the production of indicators, or else we communicate wrong messages!) Thank you!