artificial recharge of fresh water in the belgian coastal dunes
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Artificial Recharge of Fresh Water in the Belgian Coastal Dunes. Alexander Vandenbohede , Luc Lebbe and Emmanuel Van Houtte. Research Unit Groundwater M odelling Ghent University, Belgium. Intermunicipal Water Company of the Veurne region (IWVA). - PowerPoint PPT PresentationTRANSCRIPT
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Artificial Recharge of Fresh Water in the Belgian Coastal DunesAlexander Vandenbohede, Luc Lebbe and Emmanuel Van HoutteResearch Unit Groundwater ModellingGhent University, BelgiumIntermunicipal Water Company of the Veurne region (IWVA)
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Very low mineralisation of source water for recharge: 50 mg/l
Extraction wells surrounding pondsInfiltration of 2.5 million m/yearExtraction of 3.5 million m/year
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Borehole measurements
Sedimentological data
Head observations
Chemical data
Tracer test3D density dependent flow transport modelling
MOCDENS3D Visual MOCDENS3D
Hydrochemistry
Hydrosomes (water bodies) Important processes
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Fresh water heads
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Fresh water heads
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Fresh water heads
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Replacement of dune water withrecharged water
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Residence times of recharged water
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Residence times of recharged water
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Hydrochemistry
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Hydrochemistry
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Hydrochemistry
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Conclusions More water is extracted less water dune water is extracted
Positive effects on drawdowns Natural groundwater flow is partially restored Ecological implications
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Conclusions Extracted water is mix of artificial recharged water and dune water
Extracted water is mix of water with a large spectrum of residence times (30 days to 5 years)
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Conclusions Source water for artificial recharge is of very low mineralisation 50 mg/l vs 500 mg/l for dune water
Distinct water types: dune water, extracted water, recharge water, recharged water in aquifer
Most important reactions: carbonate dissolution consumption of oxygen/nitrate oxidation of sulphide minerals