Groundwater Compliance and Trends: Guidance Document on Threshold Values and Status Assessment

1. WGC-2Status Compliance and Trends guidance document Johannes Grath Rob Ward Berlin – 3 May 2007 European Commission - DG Environment Unit D.2: Water and Marine

2. Working Group C (2007-2009)Activity WGC-2 (Status compliance & trends) • Objectives • Activity 2 aims to develop a guidance documenton a common methodology to establish groundwater threshold values and on status compliance & trend assessmentalong the provisions set by the new Groundwater Directive. The activity will cover: • Adoption of a common methodology for the establishment of groundwater threshold values based on the outcome of the methodology developed by the BRIDGE project, and exchanges of experiences among the Member States in support of the new Groundwater Directive. • Development of the "status compliance & trends" guidance document, concerning both quantitative and chemical status issues. • With respect to trend assessment, the document will be largely based on the technical report developed in 2002, and will provide recommendations to Member States on how to undertake and interpret trend studies (including considerations on lag time of groundwater systems and how to integrate this in trend assessment);

3. Working Group C (2007-2009)Activity WGC-2 (Status compliance & trends) Currently drafting of 3 parts • Chemical status assessment – version 1.0(draft text) • Trend assessment – version 0.1(list of content) • Quantitative status assessment – version 0.2(basic elements) Discussion of drafts in DG meeting 2 May 2007

4. Chemical Status assessment

5. Working Group C (2007-2009)Activity WGC-2 (Status compliance & trends) Chemical Status assessment • Legal background and requirements • General principles • Guidance for testing • Test if there is an exceedances at a monitoring point • If yes, following further tests: • Significant env. risk or significant impairment of human uses • Saline or other intrusion • Significant diminution of quality of aquatic ecosystem • Significant diminution of quality of terrestrial ecosystem • Drinking Water Protected Areas (DWPA) test • Annex: Data aggregation methods

6. Chemical Status assessment Tests in case of exceedance of GW-QS or TV

7. Working Group C (2007-2009)Activity WGC-2 (Status compliance & trends) Elements of compliance testing • Need for data aggregation • Extent of exceedance • Confidence in the assessment • Location of exceedance Flow charts for each test Methods for • Data aggregation, • Assessment of extent of exceedance • Compliance in the assessment

8. Quantitative Status assessment

9. Quantitative Status assessment 1. Legal background Definition of good quantitative status • WFD Annex V2.1.2 • Good status requires GWB to meet a series of conditions • Good status of GWB relies on protection (objectives) of other parts of water environment Procedure • Unlike chemical status no formal procedure • GWDD does not cover Quantitative Status

10. Quantitative Status assessment 4. Classification • Viable classification system needs to address individual elements of good status • Status comprises two parts: • overall measure of water balance • supplementary detailed aims • Framework of four tests proposed • Water balance test • Surface water test • GWDTE test • Saline intrusion test

11. Trend assessment

12. Working Group C (2007-2009)Activity WGC-2 (Status compliance & trends) Trend assessment • largely based on the technical report developed in 2002 (WG 2.8), • Further MS experience will also be considered • will provide recommendations to Member States on how to undertake and interpret trend studies (including considerations on lag time of groundwater systems and how to integrate this in trend assessment);

13. Finally ...

14. Working Group C (2007-2009)Activity WGC-2 (Status compliance & trends) Finally 1 guidance& close integration Common methodology for threshold value derivation Groundwater Protected Areas guidance DWPA WG 2.8 Groundwater Statistics Direct and indirect inputs guidance

15. Groundwater Quantitative Status Groundwater Chemical Status G G TEST 1: Saline or other intrusions P P G G P P TEST 2: Surface Water TEST 3: Groundwater Dependent Terrestrial Ecosystems G G P P TEST 4: Drinking Water Protected Areas G P G TEST 5: General Quality Assessment P G TEST 6: Water Balance P GOOD POOR GOOD POOR The results of each test are combined for overall classification of POOR or GOOD STATUS for both quantity and chemical. The worst result is reported for the groundwater body. Overall status assessment

16. Working Group C (2007-2009)Activity WGC-2 (Status compliance & trends) Report from Drafting Group meeting • Integration of the relationship in GWD between chemical status assessment, prevent and limit (Art. 6) and the respective guidance document, required measures at individual sites in case of exceedance according to Art. 4.5 … • Basis for assessment: Arithmetic mean value at each monitoring point. Further elaboration about period and calculation of the mean at site level. • Strengthen importance of IMPRESS information and conceptual model (e.g. land use, vulnerability, risk assessment, …) for assessment procedure • Extent of exceedance: Percentage values demonstrated via test cases • Saline intrusion • Differentiate between vertical and horizontal intrusion / • Regional problem and point problem • Application of threshold values for performing the different tests • Consideration MS trend assessment experience

17. Working Group C (2007-2009)Activity WGC-2 (Status compliance & trends) Tentative timetable • 23 May Distribution of revised draft to WGC-2main emphasis on chemical status assessment • 3 weeks time for comments • Parallel further elaboration of quantity and trends – distribution before Lisbon • 21 September 2007 – Lisbon: WG C plenary meeting linked to IAH groundwater conference