Modelling of nitrate transport in the Mateur aquifer (Tunisia)hydrologie.org/redbooks/a269/P269 description, conten… · Web viewedited by Hans Gehrels, Norman E. Peters, Eduard

Impact of Human Activity on Groundwater Dynamics edited by Hans Gehrels, Norman E. Peters, Eduard Hoehn, Karsten Jensen, Chris Leibundgut, Jasper Griffioen, Bruce Webb & Willem Jan Zaadnoordijk IAHS Publication no. 269 (published July 2001) in the IAHS Series of Proceedings and ReportsISBN 1-901502-56-2; 369 + x pp.; price £ 59.50

Human activities are intricately linked to the evolution and dynamics of groundwater quantity and quality. Given the alarming rate of land-use change globally, it is important to understand the linkages between land-use change and groundwater dynamics, as land use affects the quantity and chemical quality of recharge water. The recharge directly determines the natural dynamic behaviour of the groundwater system, and is (hence) often the most important driving force in groundwater systems. In many areas, groundwater is the major source of surface water, and in others, surface water infiltration is a major source of recharge. Consequently, understanding the interaction of groundwater and surface water is important to the understanding of groundwater dynamics. Geochemical aquifer characteristics also have to be quantified to enable prediction of both the movement and contamination of groundwater.

In this book, the impact of a number of human activities on groundwater dynamics and resources, such as urbanization, land-use change and groundwater contamination is evaluated. In addition, several hydrological processes that need to be known to adequately assess the impact of these activities, such as methods for quantifying recharge, for geochemical characterization of aquifers, and for the modelling of contamination transport, are investigated.

The volume is a compilation of 53 papers presented at a symposium at Maastricht (Sixth IAHS General Assembly, July 2001), which was jointly convened by the IAHS International Commissions on Water Quality, Groundwater, Water Resources Systems, Tracers, Atmosphere–Soil–Vegetation Relations, and the International Atomic Energy Agency (IAEA), The book is subdivided into five themes:

Quantification of groundwater rechargeUrbanization and land use change Groundwater–surface water interaction Aquifer characterization and transport modelling Groundwater contamination

Contents

Preface by Hans Gehrels v

1 Quantification of Groundwater Recharge

Method for spatially distributed modelling of evapotranspiration and fast runoff components to describe large-scale groundwater recharge Volker Armbruster & Chris Leibundgut 3

WetSpass: a flexible, GIS based, distributed recharge methodology for regional groundwater modelling Okke Batelaan & Florimond De Smedt 11

Measurements of groundwater recharge rate and unsaturated convective chemical fluxes by suction controlled lysimeter Ken’ichirou Kosugi & Masanori Katsuyama 19

Estimating recharge values using hydrochemical and geological data: a case study from the semiarid Kalahari catchment of northern Namibia Heike Klock, Christoph Külls & Peter Udluft 25

Estimating recharge in UK catchments Paul Hulme, Ken Rushton & Steve Fletcher 33

Calibration of groundwater recharge and hydraulic conductivity for the aquifer system beneath the city of Milan (Italy) Mauro Giudici, Fabiano Colpo, Giansilvio Ponzini, Emanuele Romano & Guido Parravicini 43

The method of impulse response moments: a new method integrating time series-, groundwater- and eco-hydrological modelling Jos Von Asmuth & Kees Maas

51

The effects of human interventions on groundwater recharge E. P. Querner 59

Groundwater recharge increase induced by land-use change: comparison of hydrodynamic and isotopic estimates in semiarid Niger Guillaume Favreau, Christian Leduc & Christelle Marlin 67

Estimation de la recharge et modélisation de nappe en zone aride: cas de la nappe de Kairouan, Tunisie Yahaya Nazoumou & Mustapha Besbes 75

3-D aquifer characteristics analysis using a well database and GOCAD Tullia Bonomi, Angelo Cavallin & Giorgio Stelluti 89

Estimation of real and predicted infiltration recharge for the irrigated area in southern Ukraine Nikolay Ognianik & Nina Paramonova 95

Direct groundwater recharge by rainfall in a region with a semiarid Mediterranean type climate Mohammad H. Hussein 99

2 Urbanization and Land-Use Change

Urbanization effects on the hydrology of the Atlanta area, Georgia (USA) Norman E. Peters & Seth Rose 109

Impact of land-use change on groundwater in the Punjab-Haryana plains, India R. B. Singh 117

Regional monitoring of temporal changes in groundwater quality Hans Peter Broers, Bas van der Grift & Mariëlle van Vliet 123

Water management measures in the Central Biebrza basin, Poland E. P. Querner, A. Slesicka & W. Mioduszewski 131

Dam–aquifer multisystem modelling for the Wadi Merguellil basin, Tunisia Mohamedou Ould Baba Sy & Mustapha Besbes 135

Field observation and simulation of groundwater level changes due to urbanization in the Yata River basin, Japan Guangheng Ni, Yangwen Jia, Tsuyoshi Kinouchi, Kouei Tojima, Junichi Yoshitani, Tadashi Suetsugi & Yoshihisa Kawahara 139

Effects of urbanization, land-cover changes, and groundwater flow on subsurface temperature in Japan Makoto Taniguchi, Yasuo Sakura & Yohei Uchida 143

Effects of urbanization on changes in groundwater quantity and quality in Delhi State, India S. M. Trivedi, B. R. Yadav, N. Gupta, H. Chandrasekharan & Kaushalya Ramachandran 147

Urbanization effects on groundwater quantity and quality in the Zahedan aquifer, an arid region in southeast Iran E. Khazai 155

Effects of land-use change on groundwater quality in a coastal habitat of south India R. Ramesh 161

Effects of farming system type on in situ groundwater recharge and quality in northeast India U. C. Sharma 167

3 Groundwater–Surface Water Interaction

Modelling the impact of surface water management on water conservation and water quality Peter Vermeulen, Hans Gehrels, Chris Te Stroet & Ton Kremers 173

A new approach to modelling river–aquifer interactions using a 3-D numerical model and neural networks G. Parkin, P. L. Younger, S. J. Birkinshaw, M. Murray, Z. Rao & S. Kirk 183

Analysing the capabilities and limitations of tracer tests in stream–aquifer systems Brian J. Wagner & Judson W. Harvey 191

Conservative mixing or chemically reacting: scale-dependency of processes at

the stream water–groundwater interface Gunnar Lischeid 199

Scale dependent hydraulic variability of a stream bed on an outwash plain Jesper Heidemann Langhoff, Steen Christensen & Keld R. Rasmussen 205

Reliable drinking water production at a bank filtration site by using river water level as a control factor M. H. A. Juhász-Holterman 213

4 Aquifer Characterization and Transport Modelling

Determining the reactivity of reduced components in Dutch aquifer sediments Niels Hartog, Jasper Griffioen, Pim F. van Bergen & Cornelis H. Van der Weijden 221

Redox processes in the Oderbruch aquifer (northern Germany) E. Holzbecher, G. Massmann, C. Horner & A. Pekdeger 229

Inverse modelling of groundwater flow and groundwater mass transport Johan Valstar 239

A strategy for sampling reactive aquifer sediments in drinking water well fields Hans Peter Broers 247

Analysis of the longitudinal dispersion of non-reactive solutes in long-range correlated permeability fields Aldo Fiori 255

Analytical relations between model input statistics and output reliability for verification of a numerical groundwater model Willem Jan Zaadnoordijk 263

Analytical solution and numerical evaluation of the radial symmetric convection–diffusion equation with arbitrary initial and boundary data Ed Veling 271

Tools for prediction of the acidification of aquifers in sedimentary rocks (Wingst area, northern Germany) Frido Reinstorf, Wolfgang Walther, Kerstin Heblack & Thomas Cramer 277

Experimental determination of hydrodynamic dispersion coefficients for heavy metals using compacted clay M. Zeki Camur & Hasan Yazicigil 283

The influence of soil organic matter content on soil surface charge and cadmium mobility in soil Natalia Babejova, Pavel Dlapa & Vladimir Pis 287

Aquifer storage and recovery: a feasibility study Joyce C. Wakker, Eric J. C. Castenmiller & Rob J. S. M. Beckers 291

Well ageing and its implications for well and piezometer performance Georg Houben 297

5 Groundwater Contamination

Methanogenic biodegradation of charcoal production wastes in groundwater at Kingsford, Michigan, USA E. Michael Godsy, Ean Warren & David B. Westjohn

303

Compound-specific carbon isotope analysis of a contaminant plume in Kingsford, Michigan, USA Robert L. Michel, Steve R. Silva, Bryan Bemis, E. Michael Godsy, Ean Warren & David B. Westjohn 311

Natural and anthropogenic factors controlling spring water quality in the southern part of the Małopolska Upland (southern Poland) Wojciech Chełmicki & Janusz Siwek 317

Lead contamination of groundwater in the northeast of Buenos Aires Province, Argentina Jacqueline Köhn, Eduardo E. Kruse & Juan E. Santos 323

Effects of natural and anthropogenic factors on nitrogen fluxes in agricultural soils: a modelling study in the Saale River basin (central Europe) Valentina Krysanova, Uwe Haberlandt, Hermann Österle & Fred Hattermann 331

Modelling nitrate transport in deep aquifers: comparison of model results and field measurements Gerard J. M. Uffink 339

Modelling of nitrate transport in the Mateur aquifer (Tunisia) Jendoubi Arbia & Bouhlila Rachida 343

Role of shallow groundwater in nitrate and herbicide transport in the Kervidy agricultural catchment (Brittany, France) Jérôme Molénat & Chantal Gascuel-Odoux 347

Pesticides and nitrate in groundwater and rainwater in the province of Limburg, The Netherlands Jan van Maanen, Mike de Vaan, Bert Veldstra & Wim Hendrix 353

Relationship between the nitrate attenuation zone and groundwater flow in a typical hillslope–wetland plot in Japan Seiichiro Ioka, Norio Tase & Kuniyuki Toyama 357

Hydrogeochemical investigation of the influence of ceramic industry wastes on the Fazenda Itaqui basin, Brazil André Luiz Bonacin Silva & Raphael Hypolito 361

Key word index 367

Abstracts Publ. no. 269

________________________________________________________________________Impact of Human Activity on Groundwater Dynamics (Proceedings of a symposium held during the Sixth IAHS Scientific Assembly at Maastricht, The Netherlands, July 2001). IAHS Publ. no. 269, 2001, pp. 343–345.

Modelling of nitrate transport in the Mateur aquifer (Tunisia)

JENDOUBI ARBIA & BOUHLILA RACHIDA Laboratoire de Modélisation en Hydraulique et Environnement, ENIT, BP 37, Le Belvedère, 1002 Tunis, Tunisiae-mail: [email protected]

Abstract Groundwater nitrate concentrations in the Mateur aquifer in northern Tunisia have been increasing since the 1980s. The nitrate increase is due to agricultural activities including the increased fertilizer usage. A finite element model of flow and transport was used to evaluate pollutant sources and transport in the aquifer system. The temporal and spatial distributions of the nitrate input were estimated from the economic activities in the region which are conformable to a global nitrate budget calculated for the Mateur plain in this study. Different scenarios of possible management alternatives of agro-economic activities in the region to preserve the quality of the groundwater were evaluated. Key words groundwater; modelling; nitrate; pollution

________________________________________________________________________Impact of Human Activity on Groundwater Dynamics (Proceedings of a symposium held during the Sixth IAHS Scientific Assembly at Maastricht, The Netherlands, July 2001). IAHS Publ. no. 269, 2001, pp.3–10.

Method for spatially distributed modelling of evapotranspiration and fast runoff components to describe large-scale groundwater recharge

VOLKER ARMBRUSTER & CHRIS LEIBUNDGUTInstitute of Hydrology, University of Freiburg, Fahnenbergplatz, D-79098 Freiburg, Germanye-mail: [email protected]

Abstract A method for the determination of spatially distributed long-term mean groundwater recharge from precipitation in macroscale (several thousand km2) study areas is described. An evapotranspiration model to simulate long-term total runoff is combined with a regionalized long-term separation into fast runoff components and baseflow to account for runoff generation in mountainous regions. The first part of this contribution deals with the calibration and validation of the evapotranspiration model at 21 lysimeters. The second part deals with the development and testing of a regionalization model on 105 catchments, using multiple linear regression. It estimates the baseflow/total runoff ratio from physiographic catchment characteristics, which are important for runoff generation, for small catchments with a satisfying accuracy. Key words baseflow regionalization; evapotranspiration model; groundwater recharge; lysimeters; multiple linear regression


Dam–aquifer multisystem modelling for the Wadi Merguellil basin, Tunisia

mailto:[email protected]


MOHAMEDOU OULD BABA SY & MUSTAPHA BESBES Laboratoire d’hydraulique, Ecole nationale d’Ingénieurs de Tunis, BP 37 Le Belvedère – 1002 Tunis, Tunisiae-mail: [email protected]

Abstract The Merguellil basin (1200 km2) in Tunisia consists of four mutually dependent groundwater systems including that of Aïn Beïdha, which is closely related in the north to Wadi Merguellil, and to the south to Wadi Zeroud. The building and water filling of dams on these two wadis have modified the form of their relationship with the aquifer. Clear rises of piezo-metric levels are observed beside the two dams. These rises of piezometric levels are simulated by means of a model representing the aquifer system and the two dams which constitute the boundary conditions of the model.Key words abstraction; aquifer; dam; dam–aquifer modelling; groundwater recharge; piezometric levels; Tunisia; wells


The influence of soil organic matter content on soil surface charge and cadmium mobility in soil

NATALIA BABEJOVA Institute of Hydrology, Slovak Academy of Sciences, Racianska 75, PO Box 94, 83811 Bratislava 38, Slovakia e-mail: [email protected]

PAVEL DLAPA

Faculty of Science, Comenius University, Mlynská dolina, 84215 Bratislava, Slovakia

VLADIMIR PIS Research Institute of Irrigation, Drainage, and Landscape Engineering, Vrakunska 29, 82563 Bratislava 211, Slovakia

Abstract Rapid solute and particle transport in structured soils may be reduced by adsorption of ions and chemical material on soil adsorption sites. The influence of soil organic matter content on cadmium adsorption onto soil adsorption sites was studied for chernozem soils of the Danubian Lowland in equilibrium batch experiments (pH 3.5, 7.0, 9.0). The back-titration method was employed to obtain pH-dependent surface charge in conjunction with a potentiometric titration method. The soil surface charge and amount of Cd adsorbed increased with increasing organic carbon content. The experiments enable the prediction of the effect of changes of soil surface properties on cadmium transport in soil.Key words adsorption; back-titration; cadmium; organic matter; soil surface charge


WetSpass: a flexible, GIS based, distributed recharge methodology for regional groundwater modelling

OKKE BATELAAN & FLORIMOND DE SMEDTDepartment of Hydrology and Hydraulic Engineering, Free University Brussels, Pleinlaan 2, B-1050 Brussels, Belgiume-mail: [email protected]




Abstract Regional groundwater models used for analysing groundwater systems (infiltration–discharge relations) are often quasi-steady state and therefore need long-term average recharge input. On the other hand, the spatial variation in the recharge due to distributed land-use, soil type, slope, groundwater level, meteorological conditions, etc. can be significant and should be accounted for. Hence, WetSpass was built as a physically based methodology for estimation of the long-term average spatial patterns of surface runoff, actual evapotranspiration and groundwater recharge. The model is especially suitable for studying long-term effects of land-use changes on the water regime in a basin. The computer model was integrated in the GIS ArcView. Its set-up is extremely flexible; it allows easy new definition of natural or man-made land-use types. This paper describes the concept of the model and gives an example of a calibrated WetSpass recharge map.Key words Belgium; distributed model; GIS; recharge estimation; water balance; WetSpass


Hydrogeochemical investigation of the influence of ceramic industry wastes on the Fazenda Itaqui basin, Brazil

ANDRÉ LUIZ BONACIN SILVA & RAPHAEL HYPOLITODepartment of Sedimentary and Environmental Geology (GSA), Institute of Geosciences (IGc), University of São Paulo (USP), Laboratório de Hidrogeoquímica III, Rua do Lago 562, 05508-900 São Paulo, SP, Brazile-mail: [email protected]

Abstract Contamination from ceramic industries has been studied in an area near Santa Gertrudes, Brazil. Current investigations show that lead is the main contaminant in groundwater, soil, and river and lake sediments. Boron is also present in high concentrations, even in surface water, relative to both back-ground concentrations and standards, although it is not a typical contaminant. Other metals are occasionally found in high concentrations. Some experiments and field investigations have been done mainly to study the behaviour of lead. Their results show that lead tends to be fixed by the soil and sediment, whereas boron tends to be present in all environments. Therefore, boron may pose the highest risk for the environment and human health. The studies are on-going.Key words boron; ceramics; heavy metals; hydrogeochemistry; lead; Santa Gertrudes (Brazil)


3-D aquifer characteristics analysis using a well database and GOCAD

TULLIA BONOMIDipartimento di Scienze dell’Ambiente e del Territorio, Università degli Studi di Milano-Bicocca, Piazza della Scienza 1, I-20126 Milano, Italye-mail: [email protected]

ANGELO CAVALLINCNR, Centro di Studio per la Geodinamica Alpina e Quaternaria, Milano, Italy

GIORGIO STELLUTI


Dipartimento di Scienze dell’Ambiente e del Territorio, Università degli Studi di Milano-Bicocca, Piazza della Scienza 1, I-20126 Milano, Italy

Abstract Using a water well database, called TANGRAM, well data are stored and their stratigraphic logs are translated into alphanumeric codes. Textural well data can be translated and imported into GOCAD (Geological Object Computer Aided Design), where a set of three-dimensional (3-D) special virtual objects is easily constructed. The wells are easily located on a DTM and are defined by marker levels which correspond to the different stratigraphic layers. A hydraulic conductivity and porosity value can be assigned to each stratigraphic layer of the wells. Using the 3-D grid GOCAD object, the hydraulic conductivity and porosity values are assigned to the grid nodes. In this way the aquifer characteristics distribution is calculated over the whole 3-D volume of the hydrogeological system.Key words 3-D models; alluvial plain; aquifer characteristics; GOCAD; stratigraphic data; well database; wells


A strategy for sampling reactive aquifer sediments in drinking water well fields

HANS PETER BROERSNetherlands Institute of Applied Geoscience TNO, PO Box 6012, 2600 JA Delft, The Netherlands, and Centre of Hydrology, Faculty of Earth Sciences, University of Utrecht, PO Box 80021,3508 TA, Utrecht, The Netherlandse-mail: [email protected]

Abstract The modelling of solute transport around drinking water well fields requires information on the hydrogeochemical reactivity of the aquifer sediments. This paper describes a sampling strategy that was developed to collect reactivity data for transport modelling in phreatic well fields (PWF) and deep-well recharge systems (DWR). The scheme accounts for the hydraulic and chemical heterogeneity of the aquifer sediments. Different sampling objectives were stated for phreatic well fields and deep-well recharge systems to account for the propagation of reaction fronts relative to the main direction of geochemical variation. The sampling strategy includes two sampling stages using systematic and stratified random sampling. Sampling volumes and the use of geochemical analysis methods are discussed briefly. The approach is illustrated, calculating the breakthrough of solutes for a simple DWR case in the geochemically layered deposits of the Oostrum aquifer (The Netherlands).Key words aquifer reactivity; geochemical and hydraulic heterogeneity; sampling strategy; solute transport modelling


Regional monitoring of temporal changes in groundwater quality

HANS PETER BROERSCentre of Hydrology, Faculty of Earth Sciences, University of Utrecht, PO Box 80021, 3508 TA Utrecht, The Netherlandse-mail: [email protected]

BAS VAN DER GRIFT & MARIËLLE VAN VLIETTNO Netherlands Institute of Applied Geoscience, PO Box 6012, 2600 JA Delft, The Netherlands


Abstract Changes in agricultural practices are expected to affect groundwater quality by changing loads of nutrients and salts in the recharging groundwater. Regional monitoring networks installed to register those changes often fail to produce convincing evidence. This study presents an approach to evaluate and prove the effects of increasing and decreasing agricultural pollution on groundwater quality using a combination of trend analysis on time series and concentration–depth profiles. To reveal trends that might have become obscured by chemical reactions, additional semi-conservative parameters were introduced that are less sensitive to those reactions. Significant trends in the sampled groundwater were matched with the temporal changes of manure loads in recharging groundwater, using a groundwater age distribution that was verified using tritium concentrations. For the Noord-Brabant example, trends in the nutrient concentrations were not detected using a trend analysis. However, evidence for the increase of solute concentrations due to increasing manure loads was found for the semi-conservative parameter “oxidation capacity”. The study shows that it is possible to identify significant trends for groups of wells sampled from area-types sharing common characteristics. Key words conservative and reactive transport; groundwater quality monitoring; nitrate; time series; travel time


Experimental determination of hydrodynamic dispersion coefficients for heavy metals using compacted clay

M. ZEKI CAMUR & HASAN YAZICIGILDepartment of Geological Engineering, Middle East Technical University, 06531 Ankara, Turkeye-mail: [email protected]

Abstract Mass transport of ions through the Ankara clay liner, which was prepared under three different compaction conditions, was studied exp-erimentally on the basis of sorption, advection and hydrodynamic dispersion processes. Under optimum compaction conditions, effective porosity and hydraulic conductivity of the material were 0.32 and 0.13–0.26 10-8 cm s-1, respectively. Effective diffusion coefficients of Cd, Cl, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb and Zn ions were, respectively, 2.54, 9.51, 2.22, 2.85, 2.22, 7.93, 2.54, 3.08, 1.59, 3.17 and 2.54 ( 10-6) cm2 s-1. Two materials, prepared using half of the optimum water content but optimum energy conditions (II), and optimum water content but half of the optimum energy conditions (III), have effective porosities of 0.35 and 0.40, respectively. Hydraulic conductivities of these materials were 3.1–4.38 10-8 cm s-1 and 916–1057 10-8 cm s-1. Dispersivities were 0.96 cm and 2.0 cm in materials II and III, respectively. Key words Ankara clay; clay liner; diffusion; dispersivity; sorption; waste disposal site


Effects of urbanization on changes in groundwater quantity and quality in Delhi State, India

S. M. TRIVEDI, B. R. YADAV, N. GUPTA, H. CHANDRASEKHARAN*Water Technology Centre, *and Division of Environmental Sciences, Indian Agricultural Research Institute, New Delhi 110012, Indiae-mail: [email protected]

KAUSHALYA RAMACHANDRAN


GIS Laboratory, Central Institute for Dryland Agriculture, Hyderabad, India

Abstract Urbanization in India results in a population increase and other infrastructure developments leading to a large demand for water. For Delhi, the demands for water and population growth have increased exponentially, whereas water availability (surface and groundwater) has decreased resulting in an increase in tube well-irrigated areas. Thus, during the last 25 years, over exploitation of groundwater for industrial, domestic and irrigation purposes has occurred. The annual rainfall and associated groundwater recharge has been below normal during this period. Composite groundwater samples from 250 cased wells in villages adjacent to Delhi were collected during 1998 and compared to earlier published data. The spatial variations in anions, cations and micronutrients indicate that water quality has deteriorated in the west and northwestern parts of the city. Key words anion; cation; contamination; GIS Themes; groundwater quality; urbanization


Natural and anthropogenic factors controlling spring water quality in the southern part of the Małopolska Upland (southern Poland)

WOJCIECH CHEŁMICKI & JANUSZ SIWEKInstitute of Geography and Spatial Management, Jagiellonian University, 64 Grodzka Str., 31-044 Kraków, Polande-mail: [email protected]

Abstract A combination of mapping and principle components analysis were used to evaluate the factors controlling the hydrochemical composition of springs. From April to June 1999, 103 springs were sampled. Twenty to thirty springs were located in each of four farmland catchments (140–560 km2) that represent a change in bedrock geology across the study area in southern Poland. The base cations and bicarbonate concentrations, products of weathering, increase towards the northeast consistent with a change in the underlying bedrock geology from Triassic dolomites to Jurassic limestones and Cretaceous marls. In contrast, the spatial distributions of NO3 and PO4 concentrations are more random with respect to the bedrock geology and are more closely associated with the distribution of farmland.Key words groundwater quality; nitrate contamination; southern Poland; springs


Groundwater recharge increase induced by land-use change: comparison of hydrodynamic and isotopic estimates in semiarid Niger

GUILLAUME FAVREAU, CHRISTIAN LEDUCIRD-HydroSciences Montpellier, BP 5045, F-34032 Montpellier, Francee-mail: [email protected]

CHRISTELLE MARLINLHGI, Bât. 504, Université de Paris-Sud, F-91405 Orsay, France

Abstract In southwest Niger the Continental Terminal water table has been intensively studied over about 4000 km2. In this semiarid context, a surprising long-term water-table rise is evident; the mean rise was 0.20 m year-1 for the 1990s, and present levels are the highest ever measured

(+3.5 m since the early 1960s). This increase in groundwater reserves is explained by the heavy land clearing observed during recent decades. Hydrodynamic data were considered first. The mean recent rise of 0.20 m year-1 implies a recharge rate of at least 10 to 30 mm year -1 during the 1990s, whereas numerical modelling of a steady state in the early 1960s requires a much lower recharge. Radioisotope data were also considered. Taking into account the progressive increase in groundwater resources, the modelling of 14C and 3H contents gives a low pre-clearing value for recharge of between 0.6 and 5.0 mm year-1. All these estimates agree with an increase of groundwater recharge due to land clearing by about one order of magnitude in 40 years.Key words environmental isotopes; groundwater; land use; natural recharge; Niger; semiarid


Analysis of the longitudinal dispersion of non-reactive solutes in long-range correlated permeability fields

ALDO FIORIDipartimento di Scienze dell’Ingegneria Civile, Università di Roma Tre, Via V. Volterra 62, I-00146 Roma, Italye-mail: [email protected]

Abstract The concept of porous formations characterized by long-range correlated permeability fields has been introduced in recent years in order to explain the observed increase in dispersive parameters as a function of the observation scale, often coined as anomalous transport. One of the main purposes of the present study is to analyse the combined effects of the field and the local scales of heterogeneity in determining the transport properties of non-reactive solutes. The permeability field is assumed to be a space random function, lognormally distributed, and the transport parameters are obtained through a Lagrangian formulation of transport, by means of a few simplifying assumptions. The validity of the results obtained in the past, in particular concerning the occurrence of anomalous transport, is also checked. The results show that longitudinal dispersivity grows unbounded with the observation scale when local-scale dispersion is present, indicating that transport is always anomalous for the random fields considered. The results are at variance with those obtained in the past, under both the ergodic and the non-ergodic assumptions, which neglect local-scale dispersion.Key words anomalous transport; dispersion; heterogeneous formations; porous media


Modelling the impact of surface water management on water conservation and water quality

PETER VERMEULENDelft University of Technology, Faculty of Information Technology and Systems, Section of Applied Mathematical Analyses, PO Box 5031, 2600 GA Delft, The Netherlands e-mail: [email protected]

HANS GEHRELSDelft University of Technology, Faculty of Civil Engineering, Section of Hydrology and Ecology, PO Box 5048, 2600 GA Delft, The Netherlands; and Netherlands Institute of Applied Geoscience TNO–National Geological Survey, PO Box 6012, 2600 JA Delft, The Netherlands


CHRIS TE STROET & TON KREMERSNetherlands Institute of Applied Geoscience TNO–National Geological Survey, PO Box 6012, 2600 JA Delft, The Netherlands

Abstract A combined surface water–groundwater model was developed to investigate a new water management strategy focused on water conservation and improvement of water quality. This new strategy aims at more natural conditions by implementing a surface water control allowing for higher water level dynamics than has been common practice. A more flexible surface water level control was simulated using an adapted MODFLOW RIVER package in which the fixed river stage is replaced by a band width. Furthermore, a surface water model (QROUTE) was developed that simulates the routing of surface water through a system as a result of net infiltration and drainage in a number of distinct regions. QROUTE also calculates conservative transport resulting from surface water and groundwater components. The adapted RIVER package and the surface water–groundwater model were applied to Reeuwijk, a polder area in the Netherlands. Key words dynamic surface water control; MODFLOW RIVER package; The Netherlands; surface water routing model; water management


Methanogenic biodegradation of charcoal production wastes in groundwater at Kingsford, Michigan, USA

E. MICHAEL GODSY, EAN WARRENUS Geological Survey, 345 Middlefield Road, Menlo Park, California 94025, USAe-mail: [email protected]

DAVID B. WESTJOHNUS Geological Survey, 6250 Mercantile Way, Suite 5, Lansing, Michigan 48911, USA

Abstract A house exploded in the City of Kingsford, Michigan USA. The explosion was caused by CH4 that leaked into the basement from the surrounding soil. Evidence suggests that biodegradation of products from the distillation and spillage at or near a former wood carbonization plant site was the major source of CH4 and CO2 in the groundwater system. The plant area is directly upgradient from deep groundwater, samples of which are green-yellow in colour, have a very strong odour of burnt wood, contain high concentrations of mononuclear aromatic and phenolic compounds, and extremely high concentrations of volatile fatty acids. The majority of the dissolved compounds in these groundwater samples have been shown, using laboratory microcosms, to be anaerobically biodegradable to CH4 and CO2. The biodegradable compounds, and the amounts of CH4 and CO2 produced in the microcosms, are consistent with observations from field samples.Key words biodegradation; charcoal; contamination; groundwater; methane; wood distillation


Calibration of groundwater recharge and hydraulic conductivity for the aquifer system beneath the city of Milan (Italy)


MAURO GIUDICI, FABIANO COLPO, GIANSILVIO PONZINI, EMANUELE ROMANODipartimento di Scienze della Terra, Sezione di Geofisica, Università degli Studi di Milano, via Cicognara 7, I-20129 Milano, Italye-mail: m [email protected]

GUIDO PARRAVICINIDipartimento di Fisica, Università degli Studi di Milano and INFN, Sezione di Milano, via Celoria 16, I-20133 Milano, Italy

Abstract A quasi three-dimensional model has been developed to simulate the behaviour of the aquifer system, which is the source of drinking water for the city of Milan (Italy), and extends over an area of about 400 km2. Non continuous semipermeable layers locally separate permeable levels in a multi-layered system, consisting of one phreatic and three confined aquifers. The numerical model is a conservative finite difference scheme, with a grid spacing of 500 m. Model calibration requires determination of the hydraulic conductivities of the aquifers and the aquitards, and of the parameters describing the source/sink terms. Water extraction rates from public and private wells are known, whereas estimates of recharge due to rain infiltration and losses from buried pipes, rivers and artificial channels are uncertain. Here we improve the identification of the hydraulic conductivities and perform a sensitivity analysis on some coefficients used to quantify the aquifer recharge.Key words aquifer recharge; hydraulic conductivity; Milan (Italy); model calibration; multi-layered aquifer; sensitivity analysis


Determining the reactivity of reduced components in Dutch aquifer sediments

NIELS HARTOGDepartment of Earth Sciences, Utrecht University, PO Box 80021, 3508 TA Utrecht, The Netherlandse-mail: [email protected]

JASPER GRIFFIOENNetherlands Institute of Applied Geosciences–TNO National Geological Survey, PO Box 6012, 2600 JA Delft, The Netherlands

PIM F. VAN BERGEN & CORNELIS H. VAN DER WEIJDENDepartment of Earth Sciences, Utrecht University, PO Box 80021, 3508 TA Utrecht, The Netherlands

Abstract Sediments from a single aquifer were incubated under atmospheric conditions for 54 days to determine the reactivity of reductants present. The stoichiometric relationships between O2

consumption and CO2 production were used to evaluate the relative importance of ongoing redox processes. Respiration of bulk organic matter (BOM) and pyrite oxidation were the major processes occurring, but there was also evidence of siderite oxidation. The rates of BOM oxidation decreased continuously during the experiment. Pyrite oxidation had a maximum in its oxidation rate during the acidification process. When the acidific-ation was buffered by carbonate dissolution, the pyrite oxidation rates decreased continuously. More than one reductant in a sample could be oxidized simultaneously.Keywords aquifer sediment; organic matter oxidation; pyrite oxidation; reduction reactivity; redox processes; siderite oxidation________________________________________________________________________Impact of Human Activity on Groundwater Dynamics (Proceedings of a symposium held during the Sixth IAHS Scientific Assembly at Maastricht, The Netherlands, July 2001). IAHS Publ. no. 269, 2001, pp. 229–237.


Redox processes in the Oderbruch aquifer (northern Germany)

E. HOLZBECHER Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 310, D-12587 Berlin, Germanye-mail: [email protected]

G. MASSMANN Free University Berlin, Department of Economic- and Environmental Geology, Malteserstr. 74-100, D-12249 Berlin, Germany

C. HORNER Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 310, D-12587 Berlin, Germany

A. PEKDEGER Free University Berlin, Department of Economic- and Environmental Geology, Malteserstr. 74-100, D-12249 Berlin, Germany

Abstract A groundwater field study was conducted in the German Oderbruch, a region beside the Oder River on the border with Poland, to identify, understand, and quantify redox processes in the aquifer, which is continually recharged by river water. The results were subsequently modelled by combining a detailed redox process model including the kinetic approach outlined by STEADYSED1 (Van Cappellen & Wang, 1995) with non-stationary transport. The model accounts for several redox components in the solid and fluid phases. Non-redox reactions, such as sorption, precipitation, and dissolution are also modelled. In particular precipitation of rhodochrosite is considered. Measurements show that O2 and NO3

- are obviously consumed in the first few metres after infiltration. Mn and Fe (hydr)oxide reduction are the most relevant redox processes in the part of the aquifer observed. Mn concentrations in the groundwater, which are comparatively high with a distinct maximum at 150 m from the river, were simulated successfully. The maximum measured Mn concentration is 0.12 mmol l-1. Fe increases from 0.005 to 0.03 mmol l-1 along the groundwater streamlines.Key words geochemistry; groundwater modelling; redox processes; surface water infiltration; transport


Well ageing and its implications for well and piezometer performance

GEORG HOUBENIML/Geochemistry & Environmental Sciences Laboratory, RWTH Aachen, Suesterfeldstr. 22, D-52056 Aachen, Germanye-mail: [email protected]

Abstract Wells and piezometers are the main tools used to gain information on the hydraulic properties and water quality of aquifers. They often experience a decrease in performance over time due to the formation of scale. This leads to elevated entrance resistivity and subsequently to incorrect readings of hydraulic head, and values calculated therefrom. Iron and manganese oxihydroxides and sometimes calcite are the main constituents of well incrustations. Laboratory experiments showed that strong acids and strong reducing agents are the most efficient well rehabilitation chemicals. Field applications of combined hydro-mechanical and chemical rehabilitations support this evidence. Well performance tests are useful to quantify the extent of


well rehabilitation.Key words incrustation; iron oxihydroxide; piezometer; scale; well; well ageing


Estimating recharge in UK catchments

PAUL HULME, KEN RUSHTON & STEVE FLETCHERNational Groundwater and Contaminated Land Centre, Environment Agency, Olton Court, 10 Warwick Road, Olton, Solihull, West Midlands B92 7HX, UKe-mail: [email protected]

Abstract A review of the methods of estimating recharge in the UK is being carried out by the Environment Agency. This paper deals with two aspects of estimating recharge which occur in British conditions: (a) potential recharge, and (b) recharge when drift (rock material deposited by glacial activity) is present. Potential recharge is estimated using an approach which takes into account crop water requirements, soil type and evapotranspiration from bare soil. Recharge when drift is present is much less well understood. The key to its adequate estimation is the development of realistic conceptual models for the different processes which can occur. In order to develop and test our understanding, we need to be in full control of the mathematical representation hence this paper presents a method for estimating potential recharge which is readily updated as understanding increases. Key words drift; groundwater resources; modelling; recharge; UK


Direct groundwater recharge by rainfall in a region with a semiarid Mediterranean type climate

MOHAMMAD H. HUSSEINDepartment of Civil Engineering, Faculty of Engineering, PO Box 61160, Hoon, Libya

Abstract Direct groundwater recharge by rainfall affects groundwater development and its potential contamination with agricultural chemicals and/or wastes disposed on or into the ground. Such recharge can be simulated using the conservation of mass concept. Application to a region with a semiarid Mediterranean type climate indicated a seasonal recharge of no more than 12% of total seasonal rain on gently sloping land. Initial soil moisture and rainfall depth were found to be the most important factors affecting direct groundwater recharge from single storm events in the region.Key words conservation of mass; groundwater recharge; Mediterranean climate; neutron probe method; runoff plots; soil moisture distribution


Relationship between the nitrate attenuation zone and groundwater flow in a typical hillslope–wetland plot in Japan

SEIICHIRO IOKA, NORIO TASE & KUNIYUKI TOYAMAInstitute of Geoscience, University of Tsukuba, Ibaraki 305-8571, Japane-mail: [email protected]

Abstract More than 100 piezometers were installed in 0.01-ha hillslope–wetland plot in the Tsukuba upland (Japan) to investigate in detail the three-dimensional distribution of nitrate concentrations and groundwater flow. Nitrate is attenuated at the hillslope–wetland interface, where groundwater flow is upward. However, the decrease of nitrate concentration is not remarkable in the thick sand and gravel layer and the thin surface soil layer. Dissolved N2O concentrations and denitrification rates (activity) are correlated.Key words attenuation zone; denitrification rate; dissolved N2O; groundwater flow; interface between hillslope and wetland; Japan; nitrate


Reliable drinking water production at a bank filtration site by using river water level as a control factor

M. H. A. JUHÁSZ-HOLTERMANWatercompany Limburg (WML), Limburglaan 25, 6229 GA Maastricht, The Netherlandse-mail: [email protected]

Abstract The Roosteren well field was extended in 1998 with wells close to the River Meuse, and thereby changed from a simple groundwater plant into a more complex plant with 10% bank filtration. The aim was, however, to keep the water treatment as simple as possible. The feasibility of this aspiration was tested in a detailed pilot study which included the monitoring of water quality changes in the aquifer in a row of observation wells. The chemical, hydraulic and microbiological characteristics of both the influent river water and the aquifer proved to be closely related to fluctuations in water level of the River Meuse. The concept of pumping bank filtrate exclusively during periods of high quality river water, evolved. This was achieved by coupling the on-line monitoring system of the river and groundwater stages to the operation control system of the whole well field: specific changes in river and groundwater levels are automatically converted, using the results of flow simulation in a spreadsheet, into a signal to shut-down those wells which are known to pump River Meuse water. Key words bank filtration; flow dynamics; microbiological contamination; on-line monitoring; operation control system; redox environments in riverbanks; river characteristics


Urbanization effects on groundwater quantity and quality in the Zahedan aquifer, an arid region in southeast Iran

E. KHAZAIDepartment of Civil Engineering, University of Sistan and Baluchestan, Zahedan, Irane-mail: [email protected]

Abstract This paper investigates the quantitative and qualitative impacts of urban growth on the Zahedan aquifer (southeast Iran). Investigation revealed that the decline in groundwater level may



reach about 15 m in some places, and that the direction of groundwater flow changes towards the heavily abstracted area. The EC in some places shows a rise from 2030 to 5799 mho cm-1. The level of nitrates has increased to 143 mg l-1 in the populated area owing to return of wastewater through the absorption wells. In general it can be said that unplanned development of urbanization in the area has created a very difficult situation.Key words groundwater quality; groundwater quantity; groundwater pollution; urbanization and groundwater; Zahedan aquifer (Iran)


Estimating recharge values using hydrochemical and geological data: a case study from the semiarid Kalahari catchment of northern Namibia

HEIKE KLOCK, CHRISTOPH KÜLLS & PETER UDLUFTDepartment of Hydrogeology, University of Würzburg, Pleicherwall 1, D-97070 Würzburg, Germanye-mail: [email protected]

Abstract Only a spatially distributed approach can sufficiently describe recharge distribution in a large catchment. In this study the decreasing chloride concentration along groundwater flow paths has been used to represent recharge areas within the groundwater basin. Absolute recharge values, derived by application of the chloride balance method in the saturated zone close to the groundwater divide, have been assigned. A total recharge of 2.8 108 m3 year-1 has been evaluated for the Kalahari basin of semiarid northern Namibia draining towards the Okavango-Makgadikgadi System. The Otavi Foreland (Damara Sequence) is the most important hard rock recharge area for this catchment. Most of the recharge areas which feed the ground-water through partly unconsolidated sediments of the Kalahari Group, are restricted to flood courses.Key words chloride method; GIS; groundwater; Kalahari; Namibia; recharge; regionalization; semiarid


Lead contamination of groundwater in the northeast of Buenos Aires Province, Argentina

JACQUELINE KÖHN, EDUARDO E. KRUSE & JUAN E. SANTOSConicet, Depto de Geofísica Aplicada, Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque S/N, 1900 La Plata, Argentinae-mail: [email protected]

Abstract The progressive increase of water needs due to the expansion of urbanization and industrialization in different regions in the northeast of Buenos Aires Province, Argentina has resulted in intensive development of the groundwater resource. The main objective here is the study of two sectors of different hydrogeological features that have been contaminated by lead from industrial activities. We employ a method of characteristics combined with a mixed finite element procedure to simulate the plume evolution in time. The outcome of this investigation is the application of an efficient tool for handling water resources and evaluating the environmental impact from the transport of contaminants in groundwater. Key words groundwater; lead contamination; northeast of Buenos Aires Province, Argentina; numeric simulation; shallow aquifer



Measurements of groundwater recharge rate and unsaturated convective chemical fluxes by suction controlled lysimeter

KEN’ICHIROU KOSUGI & MASANORI KATSUYAMAGraduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japane-mail: [email protected]

Abstract A newly-developed suction controlled lysimeter was applied to measure water and solute transport in unsaturated forest soil. The lysimeter consists of a porous plate connected to a vacuum system and two tensiometers. Soil matric pressure heads are measured just above the horizontally-installed porous plate, and at the same depth in the natural soil profile, at three-second intervals. The vacuum system is automatically controlled so that the readings of the two tensiometers match each other. The lysimeter succeeded in keeping soil moisture conditions in the water-sampling profile almost identical to that in the natural soil profile. Field observation showed that about 68% of rainwater was discharged at 30 cm depth; Cl- concentrations in discharge-water showed a delayed peak compared to rainwater; NO3

- was not detected in discharge-water because of extraction by roots; and about 5200 mg m-2 of SiO2 was discharged at 30 cm depth as a result of soil weathering.Key words convective chemical fluxes; groundwater recharge; lysimeter; sampling method; soil water flux; unsaturated infiltration; water quality


Effects of natural and anthropogenic factors on nitrogen fluxes in agricultural soils: a modelling study in the Saale River basin (central Europe)

VALENTINA KRYSANOVA, UWE HABERLANDT, HERMANN ÖSTERLE & FRED HATTERMANNPotsdam Institute for Climate Impact Research, PO Box 601203, D-14412 Potsdam, Germanye-mail: [email protected]

Abstract After validation of nitrogen (N) dynamics in two mesoscale sub-basins of the Elbe, simulation experiments for analysing N leaching to groundwater were performed for a set of representative conditions using the SWIM model in the Saale River basin (23 687 km2), a tributary of the Elbe River. The area was subdivided into five climate zones, and nine represent-ative soil classes were chosen. The basic rotation and fertilization schemes were created using information obtained from environmental agencies. In addition, the effects of fertilization rates were studied. The ranges of simulated N fluxes for the basic rotation and fertilization schemes are comparable to available regional estimates, and differences between sub-regions are plausible. The relative importance of natural and anthropogenic factors affecting N leaching to groundwater for the Saale River basin was as follows: (1) soil, (2) climate, (3) fertilization rate, and (4) crop rotation. The simulation experiments provide a basis for a metamodel approach, which aims at rapid water quality assessment of large regions.Key words diffuse pollution; central Europe; integrated modelling; land use; nitrogen fluxes; nitrogen leaching to groundwater; non-point source pollution; river basin; water quality


Scale dependent hydraulic variability of a stream bed on an outwash plain

JESPER HEIDEMANN LANGHOFF, STEEN CHRISTENSEN & KELD R. RASMUSSENDepartment of Earth Sciences, University of Aarhus, Ny Munkegade, Building 520, DK-8000 Aarhus C, Denmarke-mail: [email protected]

Abstract The stream bed leakage coefficient of a small alluvial stream was estimated using three different methods based on data representing different length scales: (a) small-scale observations of seepage and hydraulic head (1 m); (b) mixed-scale observations (1 m hydraulic head combined with 500 m streamflow gain); and (c) large scale-observations of hydraulic head and streamflow gain (500 m). Thus, the mixed-scale and large-scale methods estimate the efficient leakage coefficient along a reach. The estimated log10 leakage coefficients were similar for all three estimation methods. The mixed-scale method is less time consuming then the other methods. However, when applying the mixed-scale or the large-scale method in large streams the stream reach has to be long in order to measure the streamflow gain with sufficient accuracy. The large-scale method should be preferred if the stream-bed leakage coefficient is to be used in a basin scale groundwater model.Key words leakage coefficient; mini-piezometer; seepage meter; stream bed


Conservative mixing or chemically reacting: scale-dependency of processes at the stream water–groundwater interface

GUNNAR LISCHEIDBITÖK, Department of Hydrogeology, University of Bayreuth, Dr-Hans-Frisch Str. 1-3, D-95440 Bayreuth, Germanye-mail: [email protected]

Abstract Due to hypoxic conditions, the riparian zone at the interface between groundwater and stream water can have substantial impacts on stream water quality. This was investigated in a small-forested catchment. The extension of the hypoxic zone was determined by depth oriented groundwater sampling and a steel rod survey. Concentrations of the major solutes were determined simultaneously in the stream water, the shallow and the deeper groundwater. Based on the steel rod survey, the first order stream is entirely contained within a thin hypoxic zone above the deeper oxic aquifer. In general, hypoxia has an impact on NO3

-, Fe and Mn, but not on SO4

2- concentrations in the shallow groundwater and the stream water. However, during storm flow, this zone is by-passed by a substantial portion of the runoff, which occurs in the topsoil layer above the hypoxic zone.Key words groundwater; hypoxia; riparian zone; runoff generation; stream water; water quality


Compound-specific carbon isotope analysis of a contaminant plume in Kingsford, Michigan, USA

ROBERT L. MICHEL, STEVE R. SILVA, BRYAN BEMIS, E. MICHAEL GODSY, EAN WARRENUS Geological Survey, 345 Middlefield Road, Menlo Park, California 94025, USAe-mail: [email protected]

DAVID B. WESTJOHNUS Geological Survey, 6250 Mercantile Way, Suite 5, Lansing, Michigan 48911, USA

Abstract Compound-specific isotope analysis was used to study a contaminated site near Kingsford, Michigan, USA. Organic compounds at three of the sites studied had similar 13C values indicating that the contaminant source is the same for all sites. At a fourth site, chemical and 13C values had evolved due to microbial degradation of organics, with the 13C being much heavier than the starting materials. A microcosm experiment was run to observe isotopic changes with time in the methane evolved and in compounds remaining in the water during degradation. The 13C values of the methane became heavier during the initial period of the run when volatile fatty acids were being consumed. There was an abrupt decrease in the 13C values when fatty acids had been consumed and phenols began to be utilized. The 13C value of the propionate remaining in solution also increased, similar to the results found in the field.Key words contamination; groundwater; isotopes; methane


Field observation and simulation of groundwater level changes due to urbanization in the Yata River basin, Japan

GUANGHENG NI, YANGWEN JIA, TSUYOSHI KINOUCHI, KOUEI TOJIMA, JUNICHI YOSHITANI, TADASHI SUETSUGIRiver Department, Public Works Research Institute, Ministry of Land, Infrastructure and Transport, Asahi 1, Tsukuba, Ibaraki 305-0840, Japane-mail: [email protected]

YOSHIHISA KAWAHARADepartment of Safety Systems Construction Engineering, Kagawa University, 2217-20 Hayashi-cho, Takamatsu, Kagawa 761-0396, Japan

Abstract Groundwater level changes in the Yata River basin (Japan) were investigated first by comparing the results of simultaneous field observations in 1999 and 2000, with those of the 1970s. It was found that the water levels of the shallow aquifer had fallen by a few metres; urbanization is considered to be the main reason. To predict groundwater level changes due to the further urban development in combination with construction of a new railway, a grid-based hydrological model was then applied to the basin. The calculated groundwater levels show a reasonable agreement with the observed ones. It is concluded that the groundwater level would decrease by at most 2.5 m soon after the further urban development if no mitigation alternatives are taken.Key words aquifer; groundwater level; hydrological model; urbanization; Yata River, Japan

________________________________________________________________________Impact of Human Activity on Groundwater Dynamics (Proceedings of a symposium held during the Sixth IAHS Scientific Assembly at Maastricht,


The Netherlands, July 2001). IAHS Publ. no. 269, 2001, pp. 347–351.

Role of shallow groundwater in nitrate and herbicide transport in the Kervidy agricultural catchment (Brittany, France)

JEROME MOLENAT & CHANTAL GASCUEL-ODOUXUMR Sol Agronomie et Spatialisation, Institut National de la Recherche Agronomique, Route de Saint Brieuc, F-35042 Rennes, Francee-mail: [email protected]

Abstract The objective of this study was to investigate shallow groundwater transport of nitrate and herbicides to a stream in an agricultural catchment. Nitrate and some herbicide concentrations were monitored in shallow ground-water and stream water of the Kervidy catchment (5 km2) located in French Brittany. Also, flow and the nitrate transport from groundwater to the stream were modelled. Results indicate that groundwater in the saprolite is a major store of nitrate due to relatively long hydrological residence times (up to three years). Also, some of the herbicides, particularly the triazines, moved rapidly through the soil to the groundwater suggesting that herbicides can be routed through the soils to the stream as groundwater discharge.Key words agricultural pollution; Brittany France; herbicide; nitrate; residence times; shallow groundwater


Estimation of real and predicted infiltration recharge for the irrigated area in southern Ukraine

NIKOLAY OGNIANIK & NINA PARAMONOVAThe Institute of Geological Sciences of the NAS of Ukraine, 55b O. Gonchara St, Kiev 01054, Ukrainee-mail: [email protected]

Abstract Investigations were conducted to estimate real and predicted infiltration recharge rates within the Dnieper-Molochnaya interfluve and the Steppe Crimea, Ukraine. The recharge was used to predict the impact of present and planned irrigation systems on the environment such as underflooding, salinization, and drinking groundwater quality deterioration. Current infiltration recharge was estimated for 45 000 km2 with a 4-km discretization during flow model identification. Infiltration recharge values and their uncertainties, which were obtained using direct or indirect measurements and calculations for several different sites, permitted determination only of assessed values. Predicted infiltration recharge and its concentrations were determined using vertical water and salt transport models reflecting the lithology and salinization of unsaturated soils. Investigations showed that infiltration recharge (mm year -1) is 3–10 at dry fields, 10–32 at settlements, and ranges from –50 to 300 at irrigated fields depending on crops, irrigation technique, inter-vegetative period watering as well as the thickness and lithology of the unsaturated zone (in dry periods negative recharge values occur at a water table depth of less than 2 m in the absence of drainage).Key words flow model identification; irrigation; real and predicted infiltration recharge; water and salt transport; Ukraine


A new approach to modelling river–aquifer interactions using a 3-D

numerical model and neural networks

G. PARKIN, P. L. YOUNGER, S. J. BIRKINSHAW, M. MURRAY, Z. RAOWater Resource Systems Research Laboratory, Department of Civil Engineering, University of Newcastle upon Tyne, Newcastle upon Tyne NE1 7RU, UKe-mail: [email protected]

S. KIRKEnvironment Agency, National Groundwater and Contaminated Land Centre, Olton Court, 10 Warwick Road, Olton, Solihull B92 7HX, UK

Abstract The forthcoming European Union Water Framework Directive has increased awareness of the need to evaluate the impacts of groundwater abstraction on the environment. The Environment Agency of England and Wales is responsible for water resource management, which it achieves primarily by operating a formal abstraction licensing system. Judgements made on applications for groundwater abstraction licenses need to be both systematic and defensible. A novel approach has been developed in a project for the Environment Agency which uses a combination of numerical model simulations of generic river–aquifer systems and neural networks to quantify the impacts on river flows. This approach provides a model which is very fast to run, while retaining the advantage of numerical methods of being able to represent complex conditions. The outcome of the project is a user-friendly Graphical User Interface (GUI) and embedded neural network software, which is designed for use by abstraction licensing officers. The approach is illustrated using a case study.Key words groundwater abstraction; modelling; neural networks; river–aquifer interaction


Urbanization effects on the hydrology of the Atlanta area, Georgia (USA)

NORMAN E. PETERSUS Geological Survey, 3039 Amwiler Road, Suite 130, Atlanta, Georgia 30360, USAe-mail: [email protected]

SETH ROSEDepartment of Geology, Georgia State University, Atlanta, Georgia 30303, USA

Abstract For the period from 1958 to 1996, streamflow and rainfall characteristics of a highly urbanized watershed were compared with less-urbanized and non-urbanized watersheds in the vicinity of Atlanta, Georgia (USA). Water levels in several wells completed in surficial and crystalline-rock aquifers also were evaluated. Annual runoff coefficients (runoff as a fractional percentage of precipitation) ranged from 0.31 to 0.34 and were not significantly different for the urban stream (Peachtree Creek). Peak flows for the largest 25 stormflows at Peachtree Creek were 30% to 80% greater than peak flows for the other streams. A 2-day storm recession constant for Peachtree Creek was much larger, that is streamflow decreased more rapidly than for the other streams. Average low flow of Peachtree Creek was 25 to 35% less than the other streams, possibly the result of decreased infiltration caused by the more efficient routing of storm water and the paving of groundwater recharge areas. The timing of groundwater level variations was similar annually in each well, reflecting the seasonal recharge. Although water level monitoring only began during the late 1970s and early 1980s for the two urban wells, water levels in these wells have been declining compared to non-urban wells since then. The water level decline is attributed to decreased groundwater recharge in the urban watersheds due to increased imperviousness and related rapid storm runoff. Likewise, the increased urbanization from the

1960s to the 1990s of the Peachtree Creek watershed produced more runoff than urbanization in the less urbanized Big Creek and Sweetwater Creek watersheds.Key words baseflow recession; groundwater recharge; Piedmont Province (Georgia, USA); stream runoff; urban runoff, urban watersheds; water yield


The effects of human interventions on groundwater recharge

E. P. QUERNERAlterra, PO Box 47, 6700 AA Wageningen, The Netherlandse-mail: [email protected]

Abstract Water tables in The Netherlands have fallen due to human interventions in the water regime. This has caused hydrological degradation, particularly over the last 50 years. Factors responsible for this hydrological degradation include: increased agricultural crop production, changes in land use, increased drainage, lowering of the drainage base, and increased groundwater abstraction. It is unknown, however, whether, and if so to what extent, these factors have changed the groundwater recharge rate. Therefore a study was carried out in three different regions in The Netherlands to quantify groundwater recharge using a regional hydrological model. The physically-based model SIMGRO, in which the unsaturated zone, the saturated zone and surface water are integrated, was used to predict the groundwater recharge. The calculations show that the natural recharge increases when water tables are deep. Variations in meteorological conditions over the last 50 years have a pronounced effect on the natural recharge, and the effect is greater than the changes caused by any of the human influences.Key words drainage; evapotranspiration; groundwater; hydrological degradation; recharge; The Netherlands


Water management measures in the Central Biebrza basin, Poland

E. P. QUERNER Alterra, PO Box 47, 6700 AA Wageningen, The Netherlandse-mail: [email protected]

A. SLESICKA & W. MIODUSZEWSKIInstitute for Land Reclamation and Grassland Farming (IMUZ), Falenty, Poland

Abstract The Biebrza National Park (BNP), situated in northeast Poland, represents a unique environment of wetland with meso- and eutrophic peat ecosystems. One of the dangers for the park wetland is the over-drying of the soil caused by the drainage works carried out in the past. To counterbalance the negative effects, the Biebrza National Park aims to restore the hydrology. However, farmers owning land along the rivers may experience negative effects on their farmland resulting from these measures. The physically-based groundwater and surface water model SIMGRO was used to predict the effect of raising the water levels. It was found that reduction of the discharge in the drainage canals to about 5% of the present flow, with the remaining water flowing via the rivers, leads to a considerable rewetting of the wetland area but unavoidably also leads to higher water levels in part of the agricultural area.Key words Biebrza (Poland); drainage; groundwater; hydrological degradation; river discharge; surface water


Effects of land-use change on groundwater quality in a coastal habitat of south India

R. RAMESHInstitute for Ocean Management, Anna University, Chennai 600 025, Indiae-mail: [email protected]

Abstract Groundwater samples were collected from 22 locations for a one-year period to evaluate the spatial and temporal variability in water quality. The period included pre-monsoon, monsoon, post-monsoon and summer seasons and the groundwater was collected from both open and dug wells, covering an area of 50 km2 in the Cauvery Delta (Sirkazhi) region, India. Electrical conductivity and pH were measured in situ. The major ions (HCO3, Cl, SO4, Ca, Mg, Na and K) and nutrients (NO3, NO2 and H4SiO4) were analysed. The mobility, concentration, and geo-accumulation of these elements were assessed. The spatial distributions of these elements are indicators of the different pathways of these elements entering the hydrological system during different seasons. Concentrations of total dissolved solids (TDS) and some elements, including Cl and Na, exceed the maximum permissible limits at some locations due to seawater intrusion. The concentration range of NO3 and NO2 was 5–48 mg l-1 and 0.23–2.13 mg l-1, respectively. The elevated concentration of NO3 in drinking water, are attributed to non-point sources, such as seepage from agricultural areas and effluent discharge from shrimp farms. In addition, the land-use change has been evaluated particularly with respect to rapid increase in aquaculture activities in the Cauvery Delta region.Key words aquaculture; groundwater quality; land-use change; pollution


Tools for prediction of the acidification of aquifers in sedimentary rocks (Wingst area, northern Germany)

FRIDO REINSTORF, WOLFGANG WALTHER, KERSTIN HEBLACK & THOMAS CRAMER Dresden University of Technology, Institute for Groundwater Management, D-01062 Dresden, Germany e-mail: [email protected]

Abstract Results of a recent research project carried out in a sedimentary rock aquifer in northern Germany are presented. The paper deals with various methods of identification of the status and prediction of subsurface acidification processes. For the identification of the status, laboratory methods, e.g. elution methods using drilling core material, and evaluation methods determining the chemical characteristics of the soil solution, were tested. For prediction tasks, mathematical models for mass balances, e.g. AcidProgress, and process description, e.g. SAFE, were tested and evaluated. With the aid of the process-oriented models, a prediction of the future status, e.g. a period of 140 years, can be computed given a future deposition scenario. The methods presented are suitable for decision making and problem management.Key words acidification; acidification model; acidification prediction; management tools



Effects of farming system type on in situ groundwater recharge and quality in northeast India

U. C. SHARMANational Agriculture Technology Project (NATP), PIU, LBS Center, IARI Campus, New Delhi 110012, India

Abstract A long-term study of the effects of land use on groundwater quantity and quality was conducted. Groundwater recharge was highest in newly developed land-use systems consisting of livestock-based, forestry, agri-pastoral, and agri-horti-silvi-pastoral; recharge as a percentage of annual precipitation was 99.4%, 95.3%, 98.8% and 97.2%, respectively. In contrast only 82.3% and 77.4% of the annual precipitation was recharged in the traditional systems, the bun method and shifting cultivation, respectively. Groundwater quality exceeded permissible limits for pH, and nitrate, iron and aluminium concentration in some farming systems. The new systems retained more water in situ resulting in low movement of water and nutrients out of the system. Average soil loss was 0.74 t ha-1 in new systems compared to 27 t ha-1 in traditional ones. The nutrient load in groundwater discharged from the system was 0.73, 4.2, 2.0 and 0.79 in the new systems and 27 and 21 kg ha-1 in the traditional systems, respectively. The quality of the groundwater was affected by the land use, deforestation, and nutrient and pesticide application.Key words farming systems; groundwater quality; India; in situ groundwater; recharge


Impact of land-use change on groundwater in the Punjab-Haryana plains, India

R. B. SINGHDepartment of Geography, University of Delhi, Delhi 110007, Indiae-mail: [email protected] / [email protected]

Abstract In order to fulfil the requirements for agricultural, domestic and industrial purposes, the dependency on groundwater in Punjab-Haryana plains is rapidly increasing. Agriculture is the main source of livelihood of the rural population and the heavy dependence on groundwater is evident in that groundwater is used for irrigation in 95% of the total irrigated area. Several questions which the planners and decision makers are confronted with relate to the quantity and quality of groundwater and how the groundwater resource is affected by the location of recharge areas, the temporal and spatial variability of recharge, the inter-linkage between groundwater and surface water, existing hydraulic gradients, and the water table situation, and regional groundwater flow. Major groundwater resource problems result from indiscriminate exploitation, particularly for irrigation, and contaminant inputs from a variety of sources such as urban runoff, fertilisers used in agriculture, seepage from contaminated industrial sites, and industrial discharges. Improved water availability and safe water supply can be guided by effective public policies, plans, and local technologies, in addition to political, socio-economic, and other factors. Key words groundwater depletion; groundwater monitoring; India; land-use change; quality assessment; socio-economic dimensions




Effects of urbanization, land-cover changes and groundwater flow on subsurface temperature in Japan

MAKOTO TANIGUCHIDepartment of Earth Sciences, Nara University of Education, Nara 630-8528, Japane-mail: [email protected]

YASUO SAKURADepartment of Earth Sciences, Chiba University, Chiba 263-8522, Japan

YOHEI UCHIDAGeological Survey of Japan, Tsukuba 305-8567, Japan

Abstract Inversions in temperature–depth profiles due to surface warming occur in big cities, such as Tokyo, Osaka, and Nagoya (Japan), and are attributed to urbanization, land-cover changes, and recent global warming. The surface warming extends deeper in the groundwater recharge area but is shallower in the discharge area. Thermal transport analyses, using heat conduction and convection under surface warming conditions, agree with values obtained from the water balance, hydraulic potentials, and tracer methods. The inversion due to surface warming may be a good tracer of the groundwater flow system.Key words groundwater flow; land-cover change; subsurface temperature; urbanization


Modelling nitrate transport in deep aquifers: comparison of model results and field measurements

GERARD J. M. UFFINKNational Institute of Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven, The Netherlandse-mail: [email protected]

Abstract The nitrate distribution in deep aquifers is being studied. Simulations were carried out for a study area in the east of The Netherlands (40 30 km2). Model results are compared with data from the Groundwater Quality Monitoring Network. Based on preliminary runs modifications in the model are proposed. In a second series of runs these modifications are eval-uated. A major factor is the vertical nitrate distribution. The steep vertical concentration gradients shown by the field data can only be simulated if vertical dispersion is reduced to the level of molecular diffusion. Several set-ups of the denitrification parameter are considered. Key words nitrate; nitrate modelling; particle tracking technique


Inverse modelling of groundwater flow and groundwater mass transport



JOHAN VALSTARNetherlands Institute of Applied Geoscience–TNO, National Geological Survey, PO Box 80015, 3508 TA Utrecht, The Netherlands e-mail: [email protected]

Abstract An inverse algorithm for groundwater flow and groundwater mass transport modelling has been tested for a rather heterogeneous aquifer. Results show that a limited number of measurements (four head and 45 concentration measurements) are sufficient to provide detailed information about the head and concentration distribution. The estimate of the conductivity values showed a significant improvement as the estimate captures most of the large-scale structure of the real conductivity field. Variation on a scale that is smaller than the density of the measurements cannot be estimated.Key words data analysis; groundwater modelling; heterogeneity; inverse modelling


Pesticides and nitrate in groundwater and rainwater in the province of Limburg, The Netherlands

JAN VAN MAANEN, MIKE DE VAANUniversity of Maastricht, Department of Health Risk Analysis and Toxicology, PO Box 616, 6200 MD Maastricht, The Netherlandse-mail: [email protected]

BERT VELDSTRAProvince of Limburg, Department of Environment and Water, Section of Law Enforcement, PO Box 5700, 6202 MA Maastricht, The Netherlands

WIM HENDRIXDirectorate-General of Public Works and Water Management, Directorate Limburg, PO Box 25, 6200 MA Maastricht, The Netherlands

Abstract The purpose of this study was to investigate the occurrence of high concentrations of pesticides and nitrate in groundwater and rainwater in the province of Limburg, The Netherlands. Eight wells were sampled, six in the north and two in the south, and analysed for a suite of pesticides and nitrate. Rainwater also was sampled and analysed from two locations. Triazines were detected in groundwater; atrazine and simazine exceeded the groundwater human-health standard of 100 ng l-1. In rainwater, 13 of 23 pesticides were detected, of which several had high concentrations; e.g. atrazine (>200 ng l-1). Two of the pesticides detected in rainwater (-HCH and atrazine) exceeded the groundwater standard. Seven pesticides in rainwater exceeded the Target value and three pesticides exceeded the Maximum Tolerable Risk value (DDT, heptachlor and heptachlorepoxide A), which are used as ecotoxi-cological standards in The Netherlands. For atrazine in rainwater, exceedance of the TDI (Tolerable Daily Intake) level of 0.5 µg kg -1 day-1

was observed using the model HESP. Groundwater nitrate concentrations regularly exceeded the standard of 50 mg l-1.Key words groundwater; groundwater and ecotoxicological standards; nitrate; pesticides; rainwater; risk evaluation; The Netherlands


Analytical solution and numerical evaluation of the radial symmetric



convection–diffusion equation with arbitrary initial and boundary data

ED VELINGDelft University of Technology, Faculty of Civil Engineering and Geosciences, PO Box 5048, 2600 GA Delft, The Netherlands e-mail: [email protected]

Abstract The analytical solution to the convection–diffusion equation in a radial velocity field with arbitrary initial data F(r) and an inhomogeneous mixed boundary condition G(t) at the well radius, is presented. These formulas are helpful in the interpretation of tracer injection experiments. To prevent numerical problems during the evaluation of the analytical solution, due to the oscillating character of the integrands, a more appropriate numerical inversion procedure is suggested. This new procedure circumvents oscillating integrands by deforming the Bromwich inversion integral contour through the complex plane using the steepest descent path. Along this path the integrands behave like exponentially decreasing positive functions which makes the integration easier.Key words Airy function; convection–diffusion; Laplace transform; numerical inversion; radial flow field; steepest descent


The method of impulse response moments: a new method integrating time series-, groundwater- and eco-hydrological modelling

JOS VON ASMUTH Delft University of Technology, Faculty of Civil Engineering and Geosciences, PO Box 5048, 2600 GA Delft, The Netherlands e-mail: [email protected]

KEES MAASKiwa N.V. Research and Consultancy, PO Box 1072, 3430 BB Nieuwegein, The Netherlands

Abstract The impulse response (IR) function describes the way in which the water table responds to an impulse of precipitation, and plays an important role in time series analysis. The moments of the IR function can, however, be directly calculated from both time series models and groundwater models, and can also be used in eco-hydrological models as moments characterize the dynamic behaviour of the water table. In this paper the outline of the method of impulse response moments (IRM) is presented. This method integrates the above mentioned fields of hydrological modelling as subsystems from which moments can be derived and between which moments can be mutually exchanged, thereby offering an opportunity to combine their specific advantages. Future research will focus on the further development of the IRM method and on quantifying the consequences of the assumptions made (i.e. linearity of the hydrological system and a predefined form of the IR function).Key words eco-hydrology; groundwater level fluctuations; groundwater modelling; method of impulse response moments; time series modelling; water table dynamics


Analysing the capabilities and limitations of tracer tests in stream–

aquifer systems

BRIAN J. WAGNERUS Geological Survey, 345 Middlefield Road, Menlo Park, California 94025, USAe-mail: [email protected]

JUDSON W. HARVEYUS Geological Survey, 430 National Center, Reston, Virginia 20192, USA

Abstract The goal of this study was to identify the limitations that apply when we couple conservative-tracer injection with reactive solute sampling to identify the transport and reaction processes active in a stream. Our methodology applies Monte Carlo uncertainty analysis to assess the ability of the tracer approach to identify the governing transport and reaction processes for a wide range of stream-solute transport and reaction scenarios likely to be encountered in high-gradient streams. Our analyses identified dimensionless factors that define the capabilities and limitations of the tracer approach. These factors provide a framework for comparing and contrasting alternative tracer test designs. Key words model uncertainty analysis; stream tracer test design


Aquifer storage and recovery: a feasibility study

JOYCE C. WAKKER, ERIC J. C. CASTENMILLER & ROB J. S. M. BECKERSWaterleiding Maatschappij Limburg, Postbus 1060, 6201 BB, Maastricht, The Netherlandse-mail: j [email protected]

Abstract Aquifer Storage and Recovery (ASR) is a water management technology in which an amount of water is pumped into and stored underground in a suitable aquifer during times of surplus, and recovered in times of shortage. If treated water is pumped in, a drinking water bubble, with a certain volume, is created underground and will be available for direct use when needed. The aquifer needs to be prepared to minimize the potential of water quality change during storage. The practical experience of a two-year deep infiltration test at the site of Dizon was used to design the ASR experiment at Herten, The Netherlands.Key words aquifer storage and recovery; water management technology


Estimation de la recharge et modélisation de nappe en zone aride: cas de la nappe de Kairouan, Tunisie

YAHAYA NAZOUMOU & MUSTAPHA BESBES Laboratoire de Modélisation en Hydraulique et Environnement, Ecole Nationale d’Ingénieurs de Tunis, BP 37, le Belvédère, 1002 Tunis, Tunisiee-mail: [email protected]

Résumé Le comportement hydrodynamique d’un aquifère sur un historique de 30 années de suivi piézométrique en zone semi-aride a été simulé à l’aide d’un modèle semi-couplé d’écoulements



superficiels et souterrains. L’ajustement en régime permanent sur l’état de janvier 1969 montre que les apports naturels au système aquifère s’élèvent à 65 Mm3 an-1. Le calage en transitoire sur cinq années coïncidant avec un événement exceptionnel et la validation sur un historique de 30 ans ont permis de quantifier la variation de la recharge. Le modèle simule de manière satisfaisante le comportement du système aquifère et peut ainsi être utilisé pour la prédiction de l’impact des nouveaux barrages sur l’évolution des niveaux piézométriques et de la ressource en eau du bassin.Mots clés zone aride; eaux souterraines; eaux de surface; modèle semi-couplé; recharge de nappe

Recharge Assessment and Groundwater Modelling in Arid Conditions: Case Study at Kairouan, TunisiaAbstract To study the hydrodynamic behaviour and estimate recharge of the Kairouan aquifer, a hydrological semi-coupled model integrating both surface water and groundwater flow processes has been developed. Surface water flows are modelled with a tank model, taking into account the propagation and the infiltration of floods in the wadi beds. It also provides the hydrological balance of the floods in order to quantify the efficiency of the infiltration flux. The unsaturated zone is treated as a cascade of tanks using the so-called Nash model, a global transfer approach of efficient infiltration that will reach the aquifer and constitute the recharge. Numerical resolution of the Boussinesq equation by finite-difference, associated with the transferred recharge flux then allows integration of the groundwater flow processes. The steady state calibration of the groundwater model was realized using piezometric data from January 1969. It has allowed calculation of the aquifer water budget, estimated at 65 Mm3 year-1. The unsteady state calibration has focused on the largest recorded flood which occurred in autumn 1969 and whose effects on the water table level persisted for almost five years. It has shown that approximately 192 Mm3

reached the water table from only this event. This model has been validated over the period from January 1969 to December 1998, in order to estimate recharge using all the available historical data. The results obtained demonstrate the model’s ability to simulate the groundwater behaviour and this can be used for the prediction of the impact of dam construction on the evolution of the water table level and resources of this aquifer.

Key words arid zone; surface water; groundwater water; semi-coupled model; groundwater recharge; Tunisia


Analytical relations between model input statistics and output reliability for verification of a numerical groundwater model

WILLEM JAN ZAADNOORDIJKHydrology and Ecology Section, Faculty of Civil Engineering and Technical Geosciences, Delft University of Technology, The Netherlandse-mail: [email protected]

Abstract Analytical relations between input parameters, output variables and statistics for confidence are derived in order to verify automatic parameter optimization and model reliability packages to be used with a groundwater flow simulation package. The relations are based on the analytical solution for a semi-confined circular island with an extraction well in the centre. Piezometric heads are considered as well as the capture zone of the well. The relations have been used to test the calibration and confidence module TrCalCon of the groundwater flow simulation package TRIWACO. The module allows both linear-variance and Monte-Carlo confidence calculations. The latter show that the nonlinearity of the test problem causes significantly wider confidence intervals in the model results than the output of the former, and is tested with the


analytical calculations.Key words analytic solution; automatic parameter optimization; confidence analysis; numerical model

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Modelling of nitrate transport in the Mateur aquifer (Tunisia)hydrologie.org/redbooks/a269/P269 description, conten… · Web viewedited by Hans Gehrels, Norman E. Peters, Eduard