cliwat newsletter april 2010 · the anticipated sea level rise and changes in recharge and...

NEWSLETTERISSUE 03 . . . . . . APRIL 2010

Salt water intrusion in coastal aquifers by Luc Lebbe and Gualbert Oude Essink

I n the CLIWAT project, we determine the physical im-pacts of climate change on groundwater and surfacewater systems in a part of the North Sea region. In

this newsletter, we focus on the topic of salt water intru-sion. Tools and methods are presented that are used inthe research to increase our knowledge of the presentphysical system in the coastal water system (via moni-toring) and to assess the future changes (via modelling).

The Phenomenon of Salt Water IntrusionFresh groundwater resources in many coastal regions in theworld, especially low-lying deltaic areas, are used intensivelyfor domestic, agricultural and industrial purposes. The avail-ability of huge quantities and the high quality of this freshgroundwater relative to the surface water makes it a popular

resource. In the future, the exploitation of fresh groundwa-ter resources will increase due to population and economicgrowth, intensified agricultural development, and the loss ofsurface water resources due to contamination. In addition,the anticipated sea level rise and changes in recharge andevapotranspiration patterns will exacerbate the pressures onthe coastal groundwater system. Many aquifers in low-lyingdeltaic areas already experience an intensive salt water in-trusion as well as the upconing of saline groundwater fromold marine deposits due to natural and anthropogenic causes(Figure 1 and 2, p.2). Salinisation of the aquifers can lead to asevere deterioration of the quality of existing fresh groundwa-ter resources. In addition, human interferences, such as min-ing of natural resources (water, sand, oil and gas) and landreclamation (causing subsidence) threaten coastal lowlandseven more. (cont’d./. . . p.2)

Editorial

Since the October 2009 newsletter, theCLIWAT group has been working hard inthe seven pilot areas, collecting data forthe groundwater models. The extensivefield work was carried out with a wide arrayof equipment, and included many ground-based and airborne surveys. In addition toobtaining significant and informative datasets the field work increasingly receivesmedia coverage. Especially the airbornesurveys have attracted a lot of attention.This has resulted in more than 50 news-paper articles, radio spots and TV cov-erage for the CLIWAT project during thelast year. The UN Climate Change Con-ference in December 2009 did not resultin binding CO2 emission targets. Nev-ertheless, a process towards binding tar-gets was started, but the rates of reduc-tion are lower than those already recom-mended by the Intergovernmental Panelon Climate Change (IPCC). This meansthat communities in the North Sea regionare facing higher temperatures, a greaterrise in sea level and more pronouncedchanges in precipitation patterns than wasfirst estimated. These climatic changes willundoubtedly affect groundwater systems.In order to prepare for these inevitablechanges, and to determine useful and nec-essary protection measures, it is essen-tial that the adaptation process is basedon sound knowledge derived from verifi-

able scientific research. In general, mostcountries have an idea of what to expectwhen dealing with temperature increases,changing precipitation and sea level rises.But when it comes to changes in ground-water dynamics and how to deal with therelated changes, there is far greater igno-rance. CLIWAT will employ groundwatermodels, and present strategies to deal withthe consequences of changes in ground-water systems. Communities need to knowwhich climate scenarios are most proba-ble, so that they can plan for their envi-ronmental systems including groundwater.While southern parts of Europe are facinga lack of groundwater in the future, the ma-jor problem for the North Sea region willbe how to deal with increasing groundwa-ter levels, and how to protect groundwater.In this third newsletter, the hot topic is saltwater intrusion. Especially on the coastalislands of the North Sea this is increasinglybecoming an important issue. Further-more, interesting articles about field workand water supply are presented. Last butnot least, upcoming relevant events are in-dicated in the calendar. We hope you willfind the newsletter worth reading. Feel freeto comment and post questions on our website, www.cliwat.org. This is also the placewhere you can subscribe to the newsletter,view our new GIS solutions and see resultsfrom the pilot studies.

Kind regards

Jes PedersenRegion [email protected]

Rolf JohnsenRegion [email protected]

Table of Contents

ArticlesSalt water intrusion in coastalaquifers

p. 1

Modelling climate change in theEgebjerg area

p. 5

CLIWAT press coverage p. 6The pilot survey on Terschelling p. 9Evaluation of landfill disposalboundaries

p. 10

MeetingsClimate In Practice p. 9Transnational board meeting p. 11

SALT WATER INTRUSION

About CLIWAT: Adaptive and sustainable water management and protection of society and nature in an extreme climate

The project will focus on the effects of climate change on ground-water systems. CLIWAT aims to identify the challenges caused bythe higher water levels, and to develop climate scenarios focusingon surface water and water supply as well as the impacts on build-ings. The quality changes of the groundwater resource caused bysalinisation, outwash from point sources and new demands for ir-rigation are some of the issues which will be investigated. This

will enable the North Sea Region to react more efficiently to theconsequences of climate change. The project will build on and im-prove existing geophysical and geochemical methods; these will betested in the partner regions in order to be able to develop groundwater models and furthermore recommendations for the North SeaRegion on how to deal with the consequences of increased ground-water levels.

(Continued from p.1)

Figure 1: Salt water intrusion and upconing of saline groundwaterin the coastal zone

Consequently, salinities of surface water systems increaseand land degradation due to salt damage may occur as soilsbecome more saline.

Figure 2: Conceptualisation of the (a) present and (b) future groundwater system in a low-lyingdeltaic area

Tools and methods: monitoring and modellingWe strongly believe that by combining various kinds oftools and methods, the relevant subsurface processes in the

coastal zone can be better understood. In addition, sophis-ticated numerical modelling tools make the prediction of thefuture state of water system more reliable. In CLIWAT, weare able to merge common existing techniques with newinnovative methods such as SkyTEM/HEM data (in a laternewsletter). Especially in the determination of the fresh-brackish saline distributions in the groundwater system, var-ious techniques are combined, such as groundwater sam-ples, geo-electrical borehole logs, electrical CPT, VES, EM31,EM34,groundwater extractions, CVES and TEC probe data.In this newsletter we discuss two techniques: 1) geophysicalborehole measurements, and 2) numerical modelling of vari-able density groundwater flow and coupled salt transport (weuse the code MOCDENS3D, which is similar to SEAWAT).

Geophysical borehole measurementsAs basic data for the modelling of salt water intrusion

two kinds of geophysical borehole measurements are veryimportant: 1) the electrical conductivity of the sedimentsand, 2) natural gamma radiation of the sediments. Oneof the most interesting methods to measure the electri-cal conductivity is the focused electromagnetic induction log

in an observation well with a shortscreen at maximum survey depth Thisallows the measurement of electricalconductivity of the sediments versusdepth and the collection of pore wa-ter of the sediments at the depth ofthe well screen of which electric con-ductivity can be measured. First of allthe electrical conductivity of the sedi-ments contains information about theelectrical conductivity of the pore wa-ter and in a lesser extend informationabout the porosity and the electricalconductivity of the matrix. The naturalgamma radiation contains primarily in-formation about the clay content andto a lesser extent information aboutthe porosity. The porosity and/or theformation factor are also a function ofthe pore water conductivity. By a joint

interpretation of the induction log, the natural gamma log andthe observed pore water conductivities one can be deducedthe variation of the pore water electrical conductivity versusdepth and made an estimation of the variation of the porosityand of the hydraulic conductivity versus the depth.

© CLIWATInterRegNewsletter Seecon Issue 03 2


Figure 3: Simulated evolution of the fresh-salt water distribution in north-south cross-section near the village of De Haan. Colours represents the salt water percentage (0% isfresh water (blue colour) with TDS = 500 mg/l, 100% is salt water (red colour) with TDS =28 g/l). White contour lines are fresh water heads in mTAW (Belgium national referencelevel). On vertical axis level in mTAW and horizontal axis is distance in m.

Case in Middenkust, BelgiumTo simulate the impact of sea level rise on the withdrawalof fresh groundwater in the Belgian coastal plane a specialapproach was chosen. The model program interface (SWI-FLEC3D) was developed which allows the generation of theinput files for the MOCDENS3D code with a minimum num-ber of input data. These data are generated using the hydro-geological data base of the Belgian coastal plain. This ap-proach allows to simulate the fresh-salt water flow in detail ina selected area. This selected area can even be a cross sec-tion as will be demonstrated here. This cross section is per-pendicular to the Belgian coastline, and is located near the vil-lage of De Haan and runs approximately in the N-S direction.The northern boundary is situated under the sea bed/levelabout 100 m north of the low-low water line (Figure 3).

Southbound the cross section traverses con-secutively the shore, the recent dunes, theold dunes and the polder area. The three-dimensional finite difference grid consists of114 rows, 3 columns and 34 layers. Allmodel cells of the finite difference grid havethe same squared surface with a side of 25m. All layers have the same thickness of 1m. In the middle of the modelled dune areaground water (51% of the recharge on theyoung and old dunes) is withdrawn. In thesimulation period of 250 year the sea levelrises with a velocity of 0.9 m/century. As aconsequence the freshwater head of the up-permost model cells under the shore and atthe vertical boundary under the North Searises with 0.09 m per decade. The watertable in the polder area is controlled by thesame traditional drainage system so that thefresh water head at uppermost model cellsunder the polder area and under the south-ern vertical boundary are unaltered duringthe simulation period. In Figure 3 the sim-ulated evolution of the fresh-saltwater distri-bution is shown.

Case in The Netherlands, thewhole coastal zoneIn collaboration with the Dutch HydrologicalModelling Instrument (NHI) Programme, a3D numerical model of the entire ground-water system in the Dutch low-lying coastalzone, where fresh-brackish-saline ground-water is present next to each other, has beenconstructed for CLIWAT. National databaseson topography, geology (REGIS), chlo-ride concentration (combining VES, bore-hole measurements and analyses with thebrackish-saline interface within the ZZREGISdatabase, Figure 4a) and geo-hydrology (ex-

traction rates) and hydrology (precipitation, evapotranspira-tion, drainage and water channels characteristics) are con-sulted to set up a 3D model to simulate variable-densitygroundwater flow and coupled salt transport. The model con-sists of 20.6 million active model cells of 250 by 250m2 andwill be used in the CLIWAT project to simulate the impactsof sea level rise, land subsidence, climate change (changesin groundwater recharge over seasons), and if applicable hu-man compensating measures on the Dutch fresh groundwa-ter resources. At this point in time, some preliminary resultsare shown to give an impression of the possible output of themodel (Figure 4b and 5). Figure 4b displays that the zone ofinfluence is surprisingly limited to areas within 10 km of thecoastline and the main rivers. This is because the increasedhydraulic head in the first aquifer near the coast can easily



be released through the highly perforated Holocene confininglayer.

ConclusionsBy combining various tools and methods on monitoring andmodelling, our knowledge about the most relevant processeson flow and transport processes in the groundwater systemin coastal zone on both local and regional scales will be im-proved significantly in the CLIWAT project.

Figure 4a: 3D chloride distribution in the Netherlands,based onmonitoring results and interpolation techniques

In addition, the numerical models, developed with this newknowledge, will improve the reliability of numerical results onfuture changes in coastal groundwater systems. Based on

these simulations, no-regret adaptation or mitigation mea-sures can be implemented in time to secure fresh water re-sources in the coastal zone in a changing world.

Figure 4b: Modelled increase of hydraulic heads in the first aquiferin a part of the Dutch coastal zone caused by sea level rise,

expressed in percentage of absolute sea level rise

Luc LebbeOnderzoekseenheid GrondwatermodelleringVakgroep Geologie en Bodemkunde, University of Ghent, [email protected]

Gualbert Oude EssinkUnit Subsurface and Groundwater SystemsDeltares, The [email protected]

Figure 5: a) Present chloride concentration at the bottom of the Holocene aquifer; b) Difference in chlorideconcentration at the bottom Holocene aquifer, viz. situation at 2100 for climate scenario W+ (dry climatescenario plus 85 cm sea level rise, 2100) minus present situation at 2000: red means salinisation ofgroundwater system, blue means freshening


MODELLING CLIMATE CHANGE

Modelling climate change in the Egebjerg area, Denmark:What are we going to do? by Klaus Petersen

C urrent knowledge about how subsurface watersand especially groundwater will respond to cli-mate change and climate change-driven variabil-

ity is very limited. Furthermore, many groundwater sys-tems have been distorted by human activities not nec-essarily related to climate change. Consequently, thereis an urgent and ongoing need to deal with the expectedimpact of climate change and its consequences.

The impact of climate change on specific water resources(and water supply) is closely related to local geography (ge-ological and hydrological). The Danish Meteorological In-stitute’s (DMI) predictions for the Danish climate indicatestressed groundwater resources. Additionally, a Danish re-gional study conducted by van Roosmalen et al (2007),showed that, with regards to IPCC climate change scenar-ios, geological factors are vital in determining the outcome(model predictions) on both groundwater as well as surfacewater systems. Highly consistent and detailed geo models aretherefore essential when dealing with any hydro-geologicalclimate change scenario.

Overall challenges facing water resources manage-ment:

� Increased flood risk in river basins, along coastalzones, and “groundwater-flooding”

� Decreased water availability – during summer sea-son

� Deteriorated water quality (including saltwater intru-sion)

Fieldwork and model work in Egebjerg pilot area F will incor-porate these challenges, as will the CLIWAT project, providinga lot of new knowledge on these issues.

The Egebjerg areaThe Egebjerg area is situated in eastern Jutland, near the cityof Horsens. The model area is approximately 200 km2 , andits central part (90 km2 ) is the main focus of CLIWAT (see Fig-ure 1). Land use is mainly agriculture with a few villages. Thearea supplies Horsens and surrounding villages with ground-water from wells located in aquifers 20–140 m below the sur-face. Aquifers are located in two or three levels, protected bythick layers of clay tills/clays. Buried valleys dominate the sub-surface geology, and complicate the interpretation of ground-water flow and its interaction with surface water. In general,the groundwater quality is good though there are major prob-lems with naturally occurring arsenic. However, most of thewaterworks are able to deal with the arsenic problem usingsimple water treatment. Waterworks abstract approximately3.5 mil. m3 of water per year in the central Egebjerg area.

The maximum permitted amount of groundwater that can beabstracted is 6.5 mil. m3 per year.

Figure 1: Map of Egebjerg area showing groundwater resources

A vulnerable resourcePrevious studies indicate a limited groundwater resource anda level of water abstraction that is just in balance with theamount of abstracted groundwater (3.5 mil. m3 per year). Cli-mate change impact is expected to adversely affect this bal-ance and decrease the potential water supply. In addition,the waterworks may well use the entire permissible amount(6.5 mil. m3 per year), which will almost certainly result inproblems of severe over-exploitation. Waterworks (adminis-trated by the municipality of Horsens) abstract vital amountsof groundwater in Egebjerg, and supply domestic water toHorsens and the nearby villages. The groundwater resourcesin Egebjerg must be protected to meet the current and futuredemands for domestic water. The need to adapt to the pre-dicted climate changes is urgent, and the Egebjerg project aswell as the CLIWAT project in general will provide the basison which adaptations can be made. (cont’d./. . . p.8)


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CLIWAT press coverage by Rolf Johnsen and Jörg Krywkow

T he centrefold of the 3rd issuedisplays five out of more thanfifty local and regional press ar-

ticles during the last twelve months.These five news clippings illustratehow CLIWAT activities are perceivedand discussed in The Netherlands,Denmark and Germany.� Airborne measurement of salinegroundwater, in: De Sjouw, 04/09/2009.Our colleague Arjen Kok of Vitens intro-duces the reader to airborn survey ap-proaches in order to explore sustainableand self-sufficient groundwater uptake forthe island of Terschelling in the DutchWadden Sea.� Ground measurements with ahelicopter, in: De Terschellinger,

24/09/2009. The article covers the sameissue as the previous article.� Detecting groundwater with a GroundPenetrating Radar (GPR), in: Der In-selbote, 17/07/2009. In this newspa-per GPR activities on the island of Föhr(North Friesian coast) are described. Thetwo students in the picture intent to detectgroundwater flow directions.� Geologists keep a good eye ongroundwater, in: Horsens Folkeblad,05/08/2009. This article covers CLIWATactivities in the town of Horsens. Themean surface water level in Horsens isexpected to raise between 0,5 and 1,5metres in 2070. This is due to increasinggroundwater as well as sea levels. Within

the project a large number of drillings andwater samples has been executed.� Climate change and groundwater, in:Der Inselbote, 25/06/2009. Local res-idents are concerned about the explo-ration of potential underground CO2 dis-posal sites. The article assures thereader that the seismic measurementsare not related to CO2 grouting but ex-amine the impact of climate change ongroundwater dynamics.


Jörg KrywkowSeecon Deutschland GmbH, Osnabrü[email protected]

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MODELLING CLIMATE CHANGE

Figure 2: Modelling the geology with voxels (volumetric pixels)

The main objectives of the Egebjerg projectThe main objectives of the Egebjerg pilot area are to developa 3-D geological model, to map the spatial distribution of sub-surface groundwater bodies, and to evaluate quantitative andqualitative effects of climate change on groundwater and sur-face water from simulations generated by an integrated hydro-logical model. The hydrological model will use data from theIntergovernmental Panel of Climate Change (IPCC) climatescenarios (A2 and B2). The results will provide an importantinput (as well as tool) for current and future quantitative andchemical status assessments of groundwater according to theWater Framework and Groundwater directives as well as forthe planning of strategies for flood defence. The results willalso be accompanied with guidelines and recommendationsfor the management of the water supply and the protection ofthe groundwater resources.

Output of the modelling work:

� Determine the local effect of climate change ongroundwater resources;

� Quantify and visualise the changes to groundwaterand surface water flow;

� Evaluate protection strategies and methods forgroundwater reservoirs and capture zones (wellfields) under changed climatic conditions;

� Devise guidelines for hydro-geological mapping inDenmark in the context of climate change;

� Devise guidelines for managing groundwater re-sources in relation to environmental standards,groundwater protection plans (water plans) andadaptation strategies.

The modelling work will be carried out in close coopera-tion with the Geological Survey of Denmark and Greenland(GEUS). In particular, the hydrological model will be modi-

fied in relationship to the Egebjerg area and the objectivesof the CLIWAT project. The geological modelling software isGeoScene 3D (for more details visit www.i-gis.dk), and theintegrated hydrological modelling uses the MIKE SHE soft-ware (for more details visit www.dhigroup.com). The geologyis modelled in voxels (volumetric pixels) in blocks of 5 x 100x 100 metres (see Figure 2). The geological model will becompleted in April 2010. Figure 2 illustrates a part of the in-terpreted geo model.

The Roosmalen regional studyUsing a distributed hydrological simulation model, a studyof projected regional climate change effects in Denmark ongroundwater recharge, storage and discharge to streams wascarried out by van Roosmalen et al. (2007). Increase in pre-cipitation, temperature, and potential evapotranspiration werepredicted in each of the two 30-year climate scenarios (IPCCA2 and B2). Groundwater recharge as well as resulting sub-surface storage and discharge were predicted to increase insandy soils, while only small changes were predicted in clayeysediments and soils. Climate change effects on groundwaterrecharge and discharge to streams were found to vary sea-sonally. Potential effects of climate change on water avail-ability were also predicted to vary seasonally. The geologicalfactors are vital for the results of the modelling. The resultsand methods of this study are used as a ‘path finder’ for theinvestigations and modelling work in Egebjerg. The Egebjergarea represents a local scale (clayey sediments), so it is obvi-ous its outcome should be compared with the outcome of thevan Roosmalen study, which was carried out on a regionalscale.

PerspectivesBecause of the National Groundwater Mapping Project andother national databases, a lot of groundwater data and geo-physical data are readily available in Denmark. On the basisof the existing data and models, it is possible to illustrate theeffects of climate change on a national scale but not on a lo-cal scale. Groundwater models need to be developed that canpredict local change. The availability of local-scale data anddata coverage is therefore vital for the models. Adaptationstrategies based on national or local-scale models may bequite different. Local factors more or less directly affect theadaptation strategy, for instance in the case of waterworks.The work and conclusions of pilot area Egebjerg F will makean important contribution to local-scale expert knowledge, es-pecially in clay dominated sediments. The same kind of mod-elling should be done in other geological settings to compareand evaluate the variability.

References and further reading:Danish strategy for adaptation to a changing climate, DanishGovernment publication March 2008 Kundzewicz, Z.W., L.J.Mata, N.W. Arnell, P. Döll, P. Kabat, B. Jiménez, K.A. Miller,T. Oki, Z. Sen and I.A. Shiklomanov, 2007: Freshwater re-


CLIMATE IN PRACTICE

sources and their management. Climate Change 2007: Im-pacts, Adaptation and Vulnerability. Contribution of WorkingGroup II to the Fourth Assessment Report of the Intergovern-mental Panel of Climate Change, M.L. Parry, O.F. Canziani,J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds.,Cambridge University Press, Cambridge, UK, 173-210

van Roosmalen L, Christensen BSB, Sonnenborg TO (2007)Regional difference in climate change impacts on groundwa-ter and stream discharge in Denmark, Vadoze Zone Journal,6: 554-571

Freshwater – Our most important resource. Geology andgroundwater models. No.1. April 2001, GEUS

Groundwater and Climate Change: Challenges and Possibili-ties, BGR 2008

Links:www.ipcc.ch/ (Intergovernmental Panel of Climate Change)http://gerda.geus.dk/ (Danish geophysical database)www.blst.dk/English/ (Danish Agency for Spatial and Envi-ronmental Planning)

Klaus PetersenEnvironment Centre AarhusWater and Nature DivisionDanish Ministry of the [email protected]

The pilot survey on Terschelling by Arjen Kok and Esben Auken

I n autumn 2009 a survey coast was conducted on theisland of Terschelling in the Dutch North Sea. Usingthe SkyTEM system aboard an aircraft an overall dis-

tance of 400 km was covered. The aim of the survey wasto identify the fresh-salt water boundary.

Results from the survey reveal that the fresh-salt water bound-ary can be accurately mapped together with the clay layerswhich control the groundwater flow to some extent. Further-more, the outflow of freshwater to the sea is mapped sev-eral hundred metres distance from the shore line and morethan 10 m below the North Sea surface. In March 2010 allthese field data were combined with helicopter data from an-other survey, and interpreted during a two-day meeting inÅrhus. Geophysicist from Denmark shared their knowledge

with Dutch geophysicist and hydrologists. The results corre-late significantly with CPT’s, ground-based CVES and TEMmeasurement and boreholes. With this information the exist-ing geo-hydrological model can be updated, which providesan excellent basis for modelling the effects of sea level rise.

Arjen KokVitens, The [email protected]

Esben AukenGeologisk Institut, Århus [email protected]@geo.au.dk

“Climate In Practice”– an innovative outcome of the CLIWAT project by Rolf Johnsen

D uring the last six months, Central Denmark Re-gion has gathered experts from Danish univer-sities, engineering consulting companies and

knowledge centres to discuss climate change is-sues.These workshops helped to obtain a better under-standing of climate change-induced water challenges theregion will face in the future. This project runs in parallelto the CLIWAT project.

The aim of the Climate In Practice project is to provide localbusinesses with a better knowledge platform from which theymay innovate and create new products that can address theexpected challenges related to climate change and water. Sixworkshops were held, each on its own specific topic:

Stakeholders and experts during the workshop (© KarstenArnbjerg-Nielsen)


EVALUATION OF LANDFILL DISPOSAL BOUNDARIES

� Open country (new nature, wetlands, changed condi-tions for agriculture);

� Water supply, groundwater protection, outwash of pol-lutants;

� Surface water and sewage and treatment plants andsystems;

� Safety of infrastructure, residences, buildings and othertechnical equipment;

� Planning and urban development;

� Cross sectors.

One of the key messages from the workshops was the need tohandle water locally, to prevent down stream damages duringflood events. Furthermore, it is important that people coop-erate across sectors to build the most robust and sustainablesolutions.


Evaluation of landfill disposal boundaries by means of induced polarisation andelectrical resistivity imaging by Aurélie Legaz, Esben Auken and Anders Vest Christiansen

I n November 2009, researchers from the HydroGeo-physics Group, Aarhus University started a survey ofthe former municipal landfill Eskelund (Denmark). In-

duced polarisation measurements (IP) and electrical re-sistivity tomography (ERT) were used to define the spa-tial boundaries of the dump site. The joint applicationof these two methods allows the discrimination betweenmaterials displaying an identical signature in resistivity(e.g., brine and clay).

The Eskelund landfill belongs to a complex of four land-fills,covering an area of approximately 0.15 km2. The site hasbeen uncontrolled, and was established without any kind ofmembranes, leachate capture or isolation systems.

The Århus university crew installing the rick for drilling

The waste mainly consists of domestic waste, but also in-dustrial waste including oils and chemical waste. The land-fill was established in the meadows adjacent to Århus creek.

Previous geo-chemical surveys and underground water sam-ples confirm the contamination, resulting from water seepagethrough the landfill. The substratum of the waste mainly con-sists of mud and silt; the silt layer provides only slight pro-tection from percolation from the landfills. Moreover, the siltlayer leaks at some places, which results in a direct contactbetween the waste and the underlying aquifer.The goal of this work is to characterise the spatial bound-aries of the Eskelund landfill itself, and to investigating thecontamination plume in the vicinity of the waste site. Ingeneral this work contributes to develop an efficient toolfor the characterisation of abandoned landfill areas. Ifconclusive, this tool could be applied for the recognitionof a large number of buried and abandoned dump sites

all over Europe. The overall area wasinvestigated with the collection of 12profiles of 355 m depth each. In col-laboration with Region Midtjylland, thedataset was then completed by an El-log drilling to a depth of 24 m. Thedrilling was made with the intention tocollect in-situ resistivity and inducedpolarisation data for accurate corre-lation between the geology and thegeophysical measurements. Thesedata were measured every half me-ter (an article was dedicated to thedrilling in the Århus newspapers, seehttp://stiften.dk/article/20100125/AAS/701259959/1002). Soon we will be ableto provide a 3-D model of the data withjoint interpretation of drilling informationof the near surface geology (up to 50 mdepth). As soon as these images andresults are available, they will be pub-lished on the CLIWAT web page.

Aurélie Legaz, Esben Auken and Anders Vest ChristiansenHydrogeophysics Groupwww.hgg.au.dk


CLIWAT TRANSNATIONAL BOARD MEETING

First CLIWAT transnational board meeting by Sophie Rotter

I Following the project partner meeting stakeholdersfrom the four case study countries came together forthe first transnational board meeting of the CLIWAT

project. During this meeting a broad overview of the var-ious national approaches to adapt to climate changes onwater related issues was given with regard to national,regional and local scaling levels. Clear differences couldbe mapped between the various countries.

Project partners applying card sorting method (© Klaus Hinsby)

During the discussion the most essential requirements forpolicies and measures to adapt to climate change focusingon groundwater in each of the countries could be identified.Furthermore, the participants pointed out which already ex-isting policies and measures need to be adapted. Finally, theparticipating project partners highlighted which of the identi-fied adaptation requirements could be supported by CLIWATproject results. The discussion was guided by using the socalled card sorting method which helps to structure the dis-cussion. The participants were asked to fill in a structuremaking sure that all important topics are covered and doc-umented.

In the following a short overview over the main discussionoutcomes is given. Not surprisingly, since 2008 strategies toadapt to climate change are implemented in all four countries(Belgium, Denmark, Germany, the Netherlands). However,the extent of the progress with implementation differs signifi-cantly. In Denmark and Germany currently potential impactsof climate change are mapped, and are incorporated into theplanning of potential measures on the national level (GermanAction Plan for the Adaptation in 2011). The Netherlands andBelgium, however, are already a step further having identifiedthe most effective measures to protect their countries against

damages, taking sea level rise into account. This is expressedin the Dutch Delta Programme and its counterpart in Belgium– the Sigma Plan. Moreover, in Belgium further initiatives areon the way, as for instance the Flemish Adaption Plan, whichis due in 2012. Another example is the integrated master planfor Flanders’ future safety which is supposed to keep the coastsafe until 2050.

Further differences between the coun-tries also exist in respect to activities re-garding adaptation strategies to climatechange. Due to the political systemin Belgium adaptation efforts are onlymade on regional and local level, whilstin Denmark the regions are not much in-volved at all. Discussing the most ur-gently required policy instruments andmeasures in the various countries CLI-WAT results that meet these needs wereidentified.

In Belgium for instance, groundwaterflooding is at the moment not taken intoaccount in climate change scenarios.CLIWAT will deliver models that includesthis information. Furthermore, ground-water and and surface water interactionis modelled in Zeeland as well as at theGerman-Danish boarder. The demandof the German stakeholders not to fol-low a regional but an eco-regional ap-

proach is implemented along the ‘eco region’ islands Borkum,Föhr and Terschelling. Appreciated policy instruments in Den-mark are guidelines taking climate change into account, forexample, when building roads. Policy recommendations be-ing delivered by CLIWAT based on an improved knowledge onthe potential development of groundwater bodies in the futurecould support this process. In the Netherlands the CLIWATmodels will support decision makers with regard to future landuse and water supply, which was seen as an important issueto be solved. The models are here focused on the salinisationof ground water but can also be used in other perspectives. Ina nutshell CLIWAT results will improve the knowledge on theeffect of climate change on groundwater bodies. Longer termdiscussion in society can be based on forecasts to be usedon regional level. However, there are, of course, limitationsas well. Meaningful modelling on local scale is not feasible atthe moment, and climate models introduce uncertainty whichcannot be avoided. For more information please refer to themeeting minutes on our website.

Sophie RotterSeecon Deutschland GmbH, Osnabrü[email protected]


Schedule of eventsEvents

Date Event Content Location Link29/9-1/10/2010 Deltas in Times of Cli-

mate ChangeInternational conference on climate change issues indeltas

Rotterdam, TheNetherlands

http://www.climatedeltaconference.org

18/09/2010 2. Borkumer Tag derEnergie

open house Stadtwerke Borkum,Germany

http://www.stadtwerke-borkum.de/

9-11/08/2010 XXVI Nordic Hydrologi-cal Conference

NORDIC WATER 2010: From research to watermanagement

Riga, Latvia www.nordicwater-2010.com

5-8/7/2010 iEMSs International Congress on Environmental Modellingand Software

Ottawa, Canada www.iemss.org/iemss2010

21-25/6/2010 2st4 Salt Water Intru-sion Meeting (SWIM)

SWIM21 – AZORES 2010 this year at the Universityof Azores

São Miguel, Azores,Portugal

http://www.swim21-azores2010.com/

May/June 2010 CLIWAT field measure-ments

DC/IP (AU) Århus River, Den-mark

18/5/2010 Danish national boardmeeting

National meeting of Danish CLIWAT stakeholders Bygholm Hotel,Horsens, Denmark

http://cliwat.eu/

11/12/5/2010 CLIWAT Partner Meet-ing

CLIWAT partner meeting in Akademie Sankelmark Oeversee, Germany file:www.akademie-sankelmark.de

April/July 2010 CLIWAT field measure-ments

CVES and CPT’s (Vitens) measurements at sea and in Frys-lan, Netherlands

April/June 2010 CLIWAT field measure-ments

DC/IP, magnetics and TEM (AU) H/orl/okke, Den-mark

April/May 2010 CLIWAT Field measure-ments

gravity survey (EC-Ribe) South Jutland, Den-mark

http://cliwat.eu/

12-23/04/2010 CLIWAT Field measure-ments

seismic survey by LIAG Föhr, Germany http://cliwat.eu/

11-17/4/ 2010 ICCCM10 International Conference on Coastal Conservationand Management in the Atlantic and Mediterranean

Estoril, Cascais,Portugal

http://icccm.dcea.fct.unl.pt

April 2010 CLIWAT field measure-ments

methane flux estimation (RM) Århus River, Den-mark

23/03/2010 Norddeutscher InterregIV – Wasserworkshop

Northern German Interreg IV workshop on water Bad Bevensen, Ger-many

The above dates and locations may change. The editors are neither responsible nor liable for any inconvenience resulting from suchchanges.

ImprintCLIWATInterRegNewsletter is published on a semestral base in PDF format.Press date for the April issue: 6th of April 2010Publisher: Seecon Deutschland GmbHContact: [email protected]: Sophie Rotter and Jörg Krywkow, Seecon

This newsletter is an output of the EU InterReg project CLIWAT, (Interreg IVB journal no.: 35-2-1-08). The project is partly financed bythe European Regional Development Fund under the European Union.The views expressed herein are the authors’ own and do not necessarily reflect those of the either the editorial team nor of the EuropeanCommission. Neither are the editorial team and the European Commission responsible for any data and information appearing herein orany loss, damage or injury to persons or property resulting from any use of information contained in this newsletter.Contributions: Please, contact [email protected]. The editorial team retain the right to shorten or grammatically modify authors’ articlesfor editorial purposes. Whilst the editorial team will make all effort to reproduce the contribution faithfully, it accepts no responsibility formistakes in the finally published text. Any corrections notices relating to the published articles can be requested by their authors andsent in writing to the contact address. The legally responsible editor is: Rolf Johnsen (Region Midtjylland).The source code ( format) of this newsletter was originally developed and published by Freies Magazin, is modified and pub-lished under the GNU licence for open documentation (FDL), http://www.gnu.org/copyleft/fdl.html. For the source code, please, refer [email protected] you want to print out CLIWATInterRegNewsletter, please reconsider whether or not you really need a hard copy of this issue.


cliwat newsletter april 2010 · the anticipated sea level rise and changes in recharge and...

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