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asis of the spatially dense geophysical mapping andhydrological modelling. After negotiation with AarhusCounty, Aarhus Municipality has accepted the importanceof active protection of the groundwater resources as abasis for ensuring a future drinking-water supply of goodquality. All new urban development around the city ofAarhus must take groundwater interests into consideration,and urban development will not usually be permittedin areas where natural protection of the groundwater ispoor. Moreover, plans to develop 1,000 ha of land designatedfor urban development have been abandoned in2001 as a result of the new information. In 1997, AarhusCounty Council decided that no new areas could bedesignated for urban development before spatially densehydrogeological mapping of the areas in question hadbeen carried out. It is estimated that the groundwater isprotected by clay layers in 50% of Denmark.The Water Framework Directiveand the European CommunityEuropean Community waters are under increasing pressurefrom the continuous growth in demand for sufficientquantities of good-quality water for all purposes (Thomsen1993; European Environment Agency 1995, 1999,2000, 2001). An EU directive establishing a frameworkfor Community activity in the field of water policy wasthus enacted in 2000 (EU 2000). The main aspects of thisinnovative approach to protection of the aquatic environmentare outlined in the Appendix.With respect to groundwater, the Directive specificallyrequires Member States to implement the measures necessaryto prevent, limit and remediate contamination of allbodies of groundwater in order to reduce the level ofpurification required to ensure the drinking-water supply,among other means through the establishment of “safeguardzones” for those bodies of groundwater. The goodexperience with the new geophysical methods shows thatit is possible to carry out the task without imposing majoradditional costs on consumers.ConclusionIt is expected that the site-specific groundwater protectionzones currently being established to ensure the futurewater supply in Denmark will substantially influence futureurban development and land use. It is thus importantthat the protection zones are based on spatially densehydrogeological mapping encompassing geophysical andgeochemical data. The geophysical mapping will beperformed using PACES and PATEM (now SKYTEM)combined with Ellog auger drilling studies. The sitespecificprotection maps designating the protection zonesand associated regulation of land use will be used toprevent groundwater contamination from urban developmentand agricultural activities, and for planning remediationof contaminated sites. Mapping and establishmentHydrogeology Journal (2004) 12:550–562of the groundwater protection zones will take place over a10-year period at a total cost of around e 120 million.During the 10-year period, consumers will pay the CountyCouncils a e 0.02 surcharge per m 3 of water consumed,i.e. less than e 4 per family per year. This ongoingDanish initiative to draw up spatially dense hydrogeologicalmaps of the 37% of Denmark designated as particularlyvaluable water-abstraction areas will have to beadjusted to the new EU Water Framework Directive, asthe latter encompasses all water bodies.Acknowledgements We would like to thank Aarhus CountyCouncil for encouragement throughout the project, Ejgil Pedersenand Lars Schrøder of Public Utilities of Aarhus for financial supportand trust, and David Barry for substantial support duringpreparation of the manuscript.AppendixChronology of Dense Hydrogeological Mappingin Denmark561– December 1998: the Danish Parliament decided thatthe County Councils should be responsible for detailedmapping of the water resources within a combined areaequivalent to 37% of Denmark.– August 1999: the County Councils established a technicaladvisory group responsible for coordinating thegroundwater protection scheme. Three subgroups wereestablished to solve practical problems within geophysicalmapping, hydrological modelling and geochemistryrespectively. The County Councils signed afive-year contract with the Department of Geophysics,University of Aarhus, called HydroGeophysics Group,to enhance geophysical data acquisition and interpretationthrough workshops and the development of improvedquality assurance procedures for measurementof geophysical data, data processing, modelling andanalysis software. See the website http://www.hgg.au.dk– March 2000: the County Councils signed a contractwith the Geological Survey of Denmark and Greenlandfor constructing and managing the national geophysicaldatabase. The mapping data can be transferred toand from the database via Internet. Together with thesoftware company NetNord, Aarhus County Council,the University of Aarhus, the Geological Survey ofDenmark and Greenland and the Spatial PlanningDepartment developed the geophysical database systemknown as GERDA. See the website http://gerda.geus.dk– May 2000: the County Councils signed a contract withthe Geological Survey of Denmark and Greenland toprovide instruction in the use of hydrological modelling.See the website http://vandmodel.dk/– June 2000: the Minister for the Environment issued astatutory order stipulating how the County Councilsare to implement the groundwater protection scheme(Danish EPA 2000a).DOI 10.1007/s10040-004-0345-1
562– August 2000: the Danish EPA published guidelinesfor the detailed mapping work and establishment ofgroundwater protection zones (Danish EPA 2000b).– 2001: the County Councils established action plansincluding a timetable for implementing the measuresnecessary to protect the groundwater.– 2000–2010: detailed mapping and groundwater protectionplans to be developed for 37% of Denmark.– 2000–2015: EU Water Framework Directive to beimplemented.– 2001: the County Councils signed a five-year contractwith the Department of Geology, University of Aarhus,to ensure development of new methods, amongother things for the identification of Quaternary meltwatersediments.The EU Water Framework DirectiveIn summary, the new Directive– protects all waters—rivers, lakes, coastal waters andgroundwaters,– sets ambitious objectives to ensure that all waters meet“good status” by 2015,– sets up a system of management within river basins,– ensures reduction and control of pollution from allsources such as agriculture, industry, urban areas, etc.,– ensures active participation of all stakeholders, includinglocal communities, in water management activities,and– requires water-pricing policies and ensures that thepolluter pays.ReferencesAarhus County (2001) Tunø status report 1989–1999. EnvironmentalDivision, Aarhus County http://www.nm.aaa.dk/publikat/pdf/Tuno_eng.pdfChristensen NB, Sørensen KI (1998) Surface and borehole electricand electromagnetic methods for hydrogeophysical investigations.Eur J Environ Eng Geophys 3(1):75–90Danish EPA (1999) Consolidated Act No. 130 of 26 February 1999on Water Supply etc. as amended by section 10 of Act No. 355of 2 June 1999 and Act No. 374 of 2 June 1999. http://www.mst.dk/homepageDanish EPA (2000a) Statutory Order No. 494 of 28 May 2000 ongroundwater protection plans (in Danish). Danish EPADanish EPA (2000b) Zonation. Detailed mapping of zones forprotecting the groundwater resources (in Danish). Danish EPAGuideline no 3DVGW (1995) Guidelines for drinking water protection. Part 1.Groundwater protection zones. Technical Standard W 101 (inEnglish). German Technical and Scientific Association for Gasand Water, BonnEU (2000) Directive 2000/60/EC of the European Parliament andof the Council of 23 October 2000 establishing a framework forCommunity action in the field of water policy. Official JournalEuropean Communities L 327, 22.12.2000 http://europa.eu.int/European Environment Agency (1995) Europe’s environment.The Dobris Assessment. European Environment Agency http://www.eea.eu.intEuropean Environment Agency (1999) Sustainable water use inEurope. Part 1. Sectoral use of water. European EnvironmentAgency Environmental Issue Rep no 1European Environment Agency (2000) Sustainable water use inEurope. Part 2. Demand management. European EnvironmentAgency Environmental Issue Rep no 19European Environment Agency (2001) Sustainable water use inEurope. Part 3. Extreme hydrological events: floods anddroughts. European Environment Agency Environmental IssueRep no 21Sørensen KI (1996) Pulled array continuous electrical profiling.First Break 14(3):85–90Sørensen KI, Auken E (2003) New developments in high resolutionairborne TEM instrumentation. In: Proc ASEG 16th GeophysicalConf Exhibition, February 2003, Adelaide, Australia.ASEG, Everton Park, QueenslandSørensen KI, Larsen F (1999) Ellog auger drilling: three-in-onemethod for hydrogeological data collection. GroundwaterMonitoring Remediation Fall 1999:97–101Sørensen KI, Auken E, Thomsen P (2000) TDEM in groundwatermapping—a continuous approach. In: Proc Symp Applicationof Geophysics to Engineering and Environmental Problems,Arlington, VA. Environmental and Engineering GeophysicalSociety, Wheat Ridge, CO, pp 485–492Thomsen R (1993) Future droughts, water shortages in parts ofWestern Europe. EOS Trans Am Geophys Union 74(14):161,164–65Thomsen R (1997) Water administration and planning by theCounty Councils, water supply. Danish Water Supply Association,Water Supply Denmark 65(6):296–300Thomsen R (2003) Use of protection zones and land management,restore contaminated groundwater in Denmark. EOS Trans AmGeophys Union 84(7):63. Animated version http://www.aaa.dk/nm/undersoeg/tunoe_flash_eng.htmlVrba J, Zaporozec A (1994) Guidebook on mapping groundwatervulnerability. Int Contrib Hydrogeol 16Hydrogeology Journal (2004) 12:550–562DOI 10.1007/s10040-004-0345-1
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