Annual report 2008
Water resources

Procuring knowledge to permit optimal management of our water resources

New tools for assessing future water resources
Calculations of the effects of climate change on the water cycle in Denmark show that we can expect great changes in the distribution of Danish water resources in the future. Some locations will see more frequent flooding, while others will experience water shortages. A new project, HYACINTS, has started to develop better tools to assess the effects of climate change on Danish water resources, both nationally and locally. Over the next few years, the project will develop a method to couple the climate model directly with the hydrological model, which calculates water flows underground and on the surface. "In the real world, the earth's surface and the atmosphere are constantly influencing each other and this is the effect we want to see built into the calculations of our water resources," said Jens Christian Refsgaard, research professor at GEUS and head of the project. The basic elements are the regional climate model, HIRHAM, from the Danish Meteorological Institute (DMI) and GEUS' national hydrological model - the DK model. The project will also mean that the nationwide DK model can supply better calculations of water resources in small, local areas. Finally, the project will produce comprehensive assessments of the uncertainties in the calculations to ensure the best possible forecasts for future water resources. HYACINTS methods and tools are expected to have export potential for the Danish water sector, and therefore the project will also develop methods to estimate precipitation conditions by using satellite data, especially in the Third World where there is often a lack of data and where the mountainous landscape greatly influences the distribution of precipitation. The project includes participants from the University of Copenhagen, the University of Aarhus, GEUS, DMI, DHI and the consulting firms Alectia Aqua and GRAS, the water companies Københavns Energi, Aarhus Kommunale Værker and Odense Vandselskab as well as Environment Centres Roskilde and Odense. HYACINTS (Hydrological Modelling for Assessing Climate Change Impacts at different Scales) is being funded by the Danish Council for Strategic Research.

Water cycle under scrutiny
Hydrological models are important tools used in management of Denmark's water resources, or to forecast the influence of climate change on the water cycle. The quality of calculations using the models depends very much on how well we can describe the processes which control the water cycle. Experience shows that it is often necessary to adjust the model calculations considerably in order to make them fit the values measured. This is partly because we lack sufficient knowledge about the processes controlling the water cycle, such as the distribution of precipitation, evaporation from different surfaces, and the exchange of water between the surface and the groundwater. In the Skjern River basin, researchers from the HOBE research centre are studying the hydrological processes in order to set up more credible models to calculate how water flows in the basin and in what quantities. In 2008, three field stations were built to measure precipitation, evaporation, temperature and groundwater charge in areas which represent the three typical Danish surfaces; meadows, fields and forests. Seismic measurements and borings have been made along the eastern coast of Ringkøbing Fjord in order to draw up a detailed description of the geology of the area as an important factor in calculations of the quantities of groundwater flowing into the sea through the seabed. The work at the centre is being carried out by researchers from the University of Copenhagen, GEUS, the University of Aarhus, the Technical University of Denmark and the Danish Meteorological Institute. HOBE (Center for Hydrology – Hydrological Observatory) is a VKR Centre of Excellence with funding from the Villum Kann Rasmussen Fonden.

Development of new sensors to monitor drinking water
The quality of drinking water is monitored today from monitoring wells drilled by the water works, from which samples are taken regularly and sent for analysis at a laboratory. GEUS is participating in the ENSOWAQ project, which is developing a number of new sensors to give early warning of polluted water. The small sensors will be built into the water intake in monitoring wells and they will continuously measure the presence of undesirable substances in drinking water. The project will develop sensors which can trace chemical substances and sensors which can measure whether there are microbiological organisms such as bacteria in the water. GEUS is heading work to develop a sensor to trace BAM, a degradation product from the pesticide dichlorobenil, which remains a problem for the groundwater despite having been banned for some time. The work is based on GEUS' earlier immunochemical research during which antibodies were developed which can show the presence of the pesticide. The method has been developed to analyse individual samples and work in 2008 aimed at adapting the method to conditions where water is continually flowing past the measuring sensor. Work was carried out in cooperation with DHI, the Technical University of Denmark, Københavns Energi, Statens Serum Institut and Mi krolab Århus A/S, with funding from the Danish Council for Strategic Research.

Assessment of the effect of climate on pesticide leaching
Climate change in Denmark may have several undesirable consequences. Climate models tell us that in the future there will be more and heavier rain, and therefore we can expect more leaching of pesticides to the groundwater, lakes and watercourses. Changes in the climate are also expected to influence the choice of crops, and new varieties are expected to be introduced, requiring the use of different pesticides. This may lead to undesirable impacts from spray pesticides on the aquatic environment. In order to put these climate effects into figures, GEUS has launched the PRECIOUS project in cooperation with the Danish Meteorological Institute (DMI) and the Fa culty of Agricultural Sciences at the University of Aarhus(DJF). Using scenarios of the future climate, choice of crop and use of pesticides, this project is to calculate changes in pesticide leaching into the aquatic environment. The work involves setting up scenarios of climate development and calculations of the fate of pesticides in the aquatic environment using different modelling tools. The assessment of the expected changes in crop choices and pesticide use will be based on studies of cultivation practices in France, Germany and the Netherlands. Changes in pesticide leaching will be calculated for two upland areas included in the Danish groundwater monitoring system. These are the Odderbæk upland in Himmerland with sandy soil, and the Lillebæk upland on Funen with clayey soil. The PRECIOUS project (Prediction of Climate Impacts on Pesticide Leaching to the Aquatic Environments) is being supported by the pesticide research programme being run by the Danish Environmental Protection Agency.

Climate and water resourcesin the North Sea region
The year 2008 saw the launch of a new research project, CLIWAT, which is to evaluate the effects of climate change on the hydrological cycle in the North Sea region in order to establish a basis for planning appropriate climate adaptation in the area. Climate models have indicated that in the future we can expect more frequent flooding in the region and increasing problems because of algae growth along coastlines caused by the expected increased leaching of nutrients from the groundwater to the sea. Finally, we can expect more migration of salt water into the groundwater because of increasing sea levels. Using calculations with hydrological models, the project will assess these effects for selected climate scenarios. Work includes collecting new geological and hydrological data along the coast and in the hinterland in selected areas in Belgium, the Netherlands, Germany and Denmark. During the year researchers started setting up a hydrological model across the border between Denmark and Germany as well as collecting field data on the current nitrate load as a basis for estimating future leaching of nutrients. Researchers from GEUS are working on the project with researchers and personnel from municipalities and regions in the four countries along the North Sea. The project is being funded by the European Regional Development Fund.