EU FP7 Mars groundwater modelling and water quality in catchment

1. Modelling Groundwater-Surface water interaction in the Dinkel catchment
Vince Kaandorp, Perry de Louw, Marijn Kuijper, Ellis Penning, Hans Peter Broers, Ype van der Velde

3. Regge and Dinkel (Waterboard Vechtstromen)

4. The Dinkel catchment
9 november 2015
Meandering streams
Riparian zones
In stream dead wood

5. But also…
9 november 2015
Straightening
Eutrophication
Obstacles
Intensive management
Loss of riparian zones

6. The Dinkel Catchment

7. The Dinkel Catchment
Groundwater is an important connection
between the stream and its catchment

8. • Amount and timing of discharge
e.g. baseflow
• Water chemistry
e.g. unpolluted water input
• Water temperature
buffers temperature, e.g. warm input in winter
9 november 2015
Why is groundwater important?

9. The groundwater component: Baseflow index (BFI)
Hydrograph separation method
0.1 very flashy river  0.9 very stable river with a high base flow proportion

10. Base Flow Index
Springendalse Beek BFI 0.8
Voltherbeek BFI 0.4
Elsbeek BFI 0.4
Graphics of year 2006
Dinkelkanaal BFI 0.1

11. What is the contribution of groundwater to lowland streams?
Springs
Drainage
Different groundwater sources…
Flow paths and travel times are important!

12. The groundwater contribution is a mix of
different groundwater components,
which have specific flow paths and travel
times.
Part is shallow, young groundwater.
Another part is deep, old groundwater.
Components vary in water chemistry.
Groundwater components: Flow path & Travel Time
Modified from Van der Grift & Klein, 2001
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13. Calculating groundwater Travel times
9 november 2015
1. Coupled Groundwater-Unsaturated zone model to calculate groundwater fluxes
iMOD + MetaSWAP
iMOD

14. Calculating groundwater Travel times
9 november 2015
1. Coupled Groundwater-Unsaturated zone model to calculate groundwater fluxes
iMOD + MetaSWAP
2. Particle tracking to calculate flow paths and travel times of infiltrating water

15. What is the contribution of groundwater to lowland streams?
Springendalse Beek

16. 9 november 2015
Changing Groundwater contribution with changing discharge
Modified from Van der Grift & Klein, 2001

17. Water Quality and Groundwater contribution age
9 november 2015

18. Conclusions
9 november 2015
Groundwater:
• Specific chemical composition
• Sustains surface water flow
• Buffers temperature
The groundwater system should be included when trying to improve
aquatic ecological conditions in streams
 The groundwater contribution varies throughout
the year
 Impact on water quantity and quality