1. Funen County HarmoniRib Workshop, Sept 21, 2006 Bruxelles Accounting for uncertainty in water management: why and how do we Dirk-I. Müller-Wohlfeil Funen County - Denmark Groundwater department

2. Funen County HarmoniRib Workshop, Sept 21, 2006 Bruxelles Outline  Why are tools for uncertainty assessment crucial for water manager’s daily work and in what respect?  How are they applied up to now?  Needs for the improvement of current procedures  Focus on output to specify input

3. Funen County HarmoniRib Workshop, Sept 21, 2006 Bruxelles Mapping and modelling in groundwater / water resources management in Denmark  Since 1998: Mapping of groundwater vulnerability leading to local action planning for protection of water resources (like WFD)  Geological mapping groundwater modelling  Politicians and legislation require reliable and crisp administrative units despite fuzziness and uncertainty in data and tools Uncertainty assessment is included in modelling

4. Funen County HarmoniRib Workshop, Sept 21, 2006 Bruxelles Applied uncertainty assessments Effects of parameter uncertainty on particle tracking to delineate groundwater protection areas in space and time Autocal / Ucode / pest  Parameter sensitivity  Optimisation  Uncertainty Problems still to be agreed upon and clarified: What time distances should be applied ? How can particle tracking used to identify most CONTRIBUTING areas?

5. Funen County HarmoniRib Workshop, Sept 21, 2006 Bruxelles Improvement of current procedures  No quality assurance with respect to “representative data”  No quality assurance with respect to “representative data”  No standardised guidelines for uncertainty assessment among the regional authorities HarmoniRib  Procedures need to be applied in an ”iterative way”  Account for various other uncertainties incl. climate change

6. Funen County HarmoniRib Workshop, Sept 21, 2006 Bruxelles Uncertainty: Water resource modelling focus on output to define input Data Geophysics Geology Soils Weather Water management Conceptual geological models Derivation simulation model Calibration 9 layer model (regional requirements) 11-layer model (local requirements) almost same modelfit Need to reconsider and extend calibration targets Sensitivity of the methods with respect to model input Need to improve gathering and modelling of input data