ANNUAL REPORT 2003
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Water resources |
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New estimate of Denmark's drinking water resources
In May 2003, GEUS published a new estimate of Denmark's exploitable drinking water resources. The estimate shows that the resources are almost halved compared to the most recent national estimate from 11 years ago -from 1.8 billion m3/year to 1.0 billion m3/year. The estimate is based on model simulations of the hydrological cycle with the national water resource model - the so-called DK model. The primary explanation for this reduction is that the new estimate has detailed calculations for the entire freshwater cycle and that impacts on watercourses and nature limit the amounts extractable from groundwater. In addition, problems with water quality in the upper groundwater aquifers mean that parts of the resources will have to be written off for a number of years. Under these preconditions, the estimate shows excessive pumping around Copenhagen, Odense and Århus and on the light soils in central and western Jutland where the need for field irrigation is large. In most of these areas, the problem is that so much water is pumped up that the effect on watercourses is too severe. In other areas, the risk of drawing nitrate and pesticides down from the upper contaminated aquifers and the release of substances such as nickel from the subsurface are limiting the amounts possible to pump up. The groundwater charge in the deeper aquifers is too small compared to the current level of pumping. Experience with the DK model is valuable in relation to the resource estimate required nationally and from river basin districts in connection with the Water Framework Directive and the national monitoring programme, NOVANA. In addition, the model is an applicable tool for the assessment of the impact of climate change on the size of Danish water resources. |
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Research on salt water in groundwater aquifers in limestone
Increasing problems are expected with regard to water quality from the many wells in eastern Zealand where water abstraction is carried out in the uppermost jointed limestone strata. In recent years, there have thus been attempts at finding deeper and better protected groundwater resources in the limestone. In some places, it has been possible to find deep-lying water-bearing fractures in the limestone that have good water quality. In other places, this has not been possible, either because of failing water flow in the deep-lying part of the limestone or because of problems with salt water. Wells and geophysical explorations have shown that the boundary between fresh and salt water in the limestone is not nearly as deep-lying as one would have expected on the basis of the traditional understanding of weight balance between fresh and salt water. It has been proved that the boundary is partly controlled by limestone's ability to let fresh water displace salt water and partly by diffusion of the salt water. With a view to making a regional strategy for utilisation of the deeper-lying part of the groundwater resources in limestone, the project studies whether the fresh water-salt water boundary is stable when pumping from deeper-lying parts of the aquifer and whether pumping will be able to draw younger contaminated groundwater further down. In addition, the project aims to elucidate how deep water-bearing fractures can be found in limestone and how great the groundwater charge is in the deeper-lying limestone aquifers. The project is being carried out with Environment & Resources DTU at the Technical University of Denmark and it is funded by Københavns Energi, Copenhagen County, Roskilde County and Frederiksborg County. |
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Patent on method for measuring the activity of bacteria
In July, GEUS filed a patent application for a method for improved measurement of bacterial activity. The method was developed in connection with research within the field of decontamination of soil. In the studies of bacterial processes in soil, there has so far been no tool to measure if bacteria are active with eg. degradation of foreign substances. It is well-known that very few bacteria are active when they are in soil and therefore this is only half the answer when we can see if the bacteria are there. By measuring messenger RNA it is possible to see directly if particular genes are expressed and whether the bacteria therefore create the process we are interested in.This invention makes it possible to reinforce the signal from mRNA without having to remove contaminated DNA from the sample. |
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Research for a common European standard
The support for implementation of the EU Water Framework Directive was continued in 2003. In addition, GEUS is participating in European research projects working with problems related to the Directive. At the end of 2003, the project BASELINE ended with the submission of a report to the EU. One object of the project was to develop a joint European method of defining natural groundwater quality. The report describes the natural groundwater quality in 25 selected aquifers in Europe. In Denmark, reports have been prepared for three aquifers. These were Miocene and Pleistocene sand aquifers in Jutland and on Funen as well as Palaeocene limestone aquifers around Copenhagen. In addition, GEUS is managing the project HarmoniRiB which intends to develop models for assessment of the uncertainty of water data and water models as well as establishing a network of representative drainage areas in Europe, from which data with uncertainty levels can be freely available for other research projects. Finally, GEUS is participating in the project HARMONICA which intends to build a bridge between research and practical implementation of the Water Framework Directive in Europe. This will be done through workshops, seminars and other information exchange. |
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Progress in the work with pesticide sensitive areas
GEUS and the Danish Institute of Agricultural Sciences are working on the development of a method for mapping of areas which are particularly sensitive to leaching of pesticides to groundwater. The project - Koncept for Udpegning af Pesticidfølsomme Arealer (KUPA - Concept for Identification of Pesticide-Sensitive Areas) - has been concentrated on developing a method for sandy soil areas and on assessing the possibilities of developing a method for areas with clay soil. In 2003, the planned laboratory analyses and most of the interpretation were completed. The results of this work show that, to a great extent, it is possible to use simple easily accessible soil parameters for calculation of leaching. In this connection, GEUS is trying to determine whether it is possible to cha-racterise leaching by means of the size of soil parameters.A further perspective of the work is that it is possible to identify areas that are particularly sensitive to leaching by means of a mapping of a small number of simple soil parameters. Furthermore, the project has shown that it can make sense to point out particularly sensitive areas even though they are only checked for a few pesticides. |
