Synthetic report on the economic

analysis including a sensitivity

analysis for each selected study

areas, and the link with the conceptual model Deliverable I2.4 of the Aquaterra EU research project

BRGM/RP-55074-FR November, 2006

C.Hérivaux, M.Bouzit, N.Graveline (BRGM) E.Ansink (WUR) P.Strosser (Acteon)

1

Project no. 505428 (GOCE) AquaTerra

Integrated Modelling of the river-sediment-soil-groundwater system; advanced tools for the management of catchment areas and river basins in the context of global change

Integrated Project

Thematic Priority: Sustainable development, global change and ecosystems

Deliverable No.: I2.4 Title: Synthetic report on the economic analysis including a sensitivity analysis for each selected study areas, and the link with the conceptual model.

Due date of deliverable: September 2006 Actual submission date: November 2006

Start date of project: 01 June 2004 Duration: 60 months

Organisation name and contact of lead contractor and other contributing partners for this deliverable: Cécile HERIVAUX; Madjid BOUZIT; Nina GRAVELINE (BRGM) Erik ANSINK (WUR) Pierre STROSSER (Acteon)

Revision: D. Darmendrail, J. Barth

Project co-funded by the European Commission within the Sixth Framework Programme (2002-2006) Dissemination Level PU Public PP Restricted to other programme participants (including the Commission Services) RE Restricted to a group specified by the consortium (including the Commission Services) X CO Confidential, only for members of the consortium (including the Commission Services)

3

SUMMARY

Through five case studies this report presents the use of the DPSIR framework to analyse the main economic activities that may exert pressures on the soil- sediment-water system of a River Basin and those that may be potentially affected by a degradation of this system. For each case study an integrated conceptual model has been developed, integrating both bio-physical processes of concern and socio-economic components. The five selected case study areas are: (i) the Geer basin and groundwater nitrate contamination (Meuse - BE); (ii) soil contamination by heavy metals in the Kempen area (Meuse – BE/NL); (iii) surface water salinisation in the central Ebro valley (Ebro – Spain); (iv) the Ksrko kotlina aquifer and groundwater agricultural diffuse pollution (Danube – Slovenia); (v) transboundary issue of low flows in the Meuse (Meuse – BE/NL).

MILESTONES REACHED (from DOW II p. 81 to 86)

I2.5 Analysis of the economic behaviours completed for study areas (BRGM, WUR) Month 26.

I2.2e. Version 4 Integrator Conceptual Model Post-Validation report and Platform for I3

I3.4. First reception and analysis of scientific results from the other SPs of Aquaterra. Month 30

The five case studies will put here the first steps of a broader collaboration/ integration between SPs. For instance in the Geer basin, the work carried out with the other SPs (BASIN, TREND) will show how physical science and socio- economic results may be integrated.

5

Glossary

CEA cost-effectiveness analysis

CBA cost benefit analysis use values values associated with both consumptive and non-consumptive use of water non-use values values that may occur when the groundwater is not devoted to any use

DGRNE Direction Générale des Ressources Naturelles et de l’ Environnement (Région Wallone)

AERM Agence de l’Eau Rhin Meuse (France)

EPIC-grid model Quantitative and qualitative modelisation of catchment hydrology and at field scale developed by the University of Gembloux

NSN Nitrate Survey Network

CILE Compagnie Intercommunale Liégeoise des Eaux

SWDE Société Wallonne de distribution des Eaux”

VMW Vlaamse Maatschappij voor Water -voorziening

AEAG Adour Garonne French Water Agency

DWU drinking water unit

CIEAU Centre d’Information de l’Ea (www.cieau.com)

CAP common agricultural policy

PIRENE project Water and Environment Integrated research project of the Walloon Region.

SUF3D model Hydrogeological model developed by the University of Liege (see BASIN deliverable)

IA Integrated Assessment

BeneKempen Flemish-Dutch envirnmental partnership

OVAM Openbare Vlaamse Afv alstoffenmaatschappij (Public Wate Agency of Flanders)

FAVV federal agency for the safety of the food chain

(IRF) irrigation return flows

CAT Consoci Aiguas de Tarragona

TDS Total dissolved solids

Table of contents

List of figures...... 11

1. Introduction...... 13

2. Methodology and economic concepts...... 15

2.1. The overall framework...... 15

2.2. Building integrated conceptual models...... 16 2.2.1. Defining boundaries and sub-systems ...... 16 2.2.2. Capturing the functioning of the different sub-systems ...... 18

2.3. From conceptual models to support to decision making...... 19

2.4. Case studies application...... 21

References ...... 22

3. The Hesbaye aquifer (Meuse, Walloon region): nitrate pollution in groundwater...... 24

3.1. Introduction – Context and aim of the study ...... 24 3.1.1. General context - Nitrate contamination of aquifers ...... 24 3.1.2. The Geer basin / Hesbaye aquifer – general characteristics...... 25 3.1.3. Overall objectives of the case study...... 25

3.2. Analysing DPSI in the Geer basin ...... 26 3.2.1. Economic activities exerting pressures on the Hesbaye aquifer (Drivers and Pressures). 26 3.2.2. Nitrate concentration in the Hesbaye aquifer (State)...... 28 3.2.3. Economic activities potentially affected by the degradation of groundwater quality (Impacts) 28 3.2.4. Integrated Conceptual model ...... 31

3.3. Capturing the functioning and relationships between the different sub systems ...... 32 3.3.1. Main factors influencing drivers and pressures on groundwater resource (from Drivers to Pressures)...... 32 3.3.2. Relationships between change in agricultural practices and evolution of nitrate concentration in groundwater (from Pressures to State) ...... 34 3.3.3. Relationships between groundwater degradation and adaptation of affected economic activities (from State to Impacts)...... 36

3.4. Conclusion...... 39

References ...... 41

4. The Kempen area (Meuse, Flanders & the Netherlands): soil contamination by heavy metals... 43

4.1. Introduction – Context and aim of the study ...... 43 4.1.1. General context – Heavy metal contamination...... 43 4.1.2. Kempen case study: General description...... 44 4.1.3. Overall objective of the case study...... 46

4.2. Applying the DPSIR framework ...... 46 4.2.1. Drivers...... 47 4.2.2. Pressures...... 47 4.2.3. State...... 48 4.2.4. Impacts of contamination ...... 49 4.2.5. Responses ...... 51

8

4.3. Identifying the relationships of the DPSIR ...... 52 4.3.1. Relationship D – P: pollution source assessment ...... 53 4.3.2. Relationship P – S: mass flux model...... 53 4.3.3. Relationship S – I ...... 53 4.3.4. Relationship R – [DPS]: scenario analysis ...... 53

4.4. Remediation Measures...... 55 4.4.1. Potential technical measures ...... 55 4.4.2. Costs of the potential technical measures...... 56

4.5. Conclusion...... 57

References ...... 58

5. Ebro River Basin (Spain): soil and water salinisation ...... 60

5.1. Introduction – Context and aim of the study ...... 60 5.1.1. General context...... 60 5.1.2. Problem – Issue ...... 61 5.1.3. Overall objective...... 61 5.1.4. Link with other AquaTerra activities ...... 61

5.2. State of the water: spatial and temporal variability of salinity in the Ebro basin...... 62 5.2.1. Surface water...... 62 5.2.2. Groundwater ...... 63

5.3. Drivers and Pressures...... 64 5.3.1. Natural contributions ...... 64 5.3.2. Diffuse pollution from agriculture...... 65 5.3.3. Industrial sources of pollution...... 68 5.3.4. Road deicing with sodium chloride...... 70 5.3.5. Waste water treatment plant residues...... 70 5.3.6. Atmospheric contribution...... 71

5.4. Impacts of salinity...... 71 5.4.1. Impacts on ecosystems...... 72 5.4.2. Impacts on the drinking water sector...... 72 5.4.3. Agriculture...... 75 5.4.4. Fisheries...... 78 5.4.5. Industry and public equipment ...... 79 5.4.6. Synthesis of the impacts of salinisation...... 80

5.5. External Drivers and tendencies : a first overview...... 80 5.5.1. Natural conditions ...... 80 5.5.2. Economic conditions - environmental and agricultural policies ...... 81

5.6. Responses-measures...... 82

5.7. Conclusion...... 83

References ...... 85

6. The Krsko kotlina aquifer (Danube, Slovenia): nitrates and pesticide pollution in groundwater 87

6.1. Introduction - Context and aim of the study...... 87 6.1.1. General context...... 87 6.1.2. The Krsko kotlina aquifer – general characteristics...... 88 6.1.3. Overall objective of the case study...... 89

9

6.2. Analysing DPSI in the Krsko aquifer...... 89 6.2.1. Main pressures & drivers...... 89 6.2.2. State...... 91 6.2.3. A preliminary review of today’s impacts: water uses affected by today’s groundwater pollution 92 6.2.4. In summary ...... 93

6.3. Looking at trends and baseline...... 93

6.4. Potential responses for restauring groundwater quality in the Krsko aquifer...... 96

6.5. Summarising the Conceptual model for the Krsko aquifer...... 98 6.5.1. Application of the DPSIR framework to the Krsko aquifer ...... 98 6.5.2. Main assumptions made for defining the system and its components ...... 100 6.5.3. Presenting the overall system considered and its components...... 100 6.5.4. Key variables for the main economic sub-systems and decision making processes considered 102

6.6. Conclusion...... 103

References ...... 107

7. Low flows in the Meuse river basin...... 108

7.1. Introduction – Context and aim of the study ...... 108

7.2. Overview of water use...... 110 7.2.1. Industry ...... 110 7.2.2. Agriculture...... 111 7.2.3. Energy...... 111 7.2.4. Navigation ...... 111 7.2.5. Drinking water ...... 111 7.2.6. Total water use...... 111

7.3. The conceptual model for the water flows in the meuse river basin ...... 113

7.4. Functioning of the different sub-systems...... 113

7.5. Conclusion...... 114

References ...... 115

8. Conclusion ...... 117

10

List of figures

Figure 1. Main soil-sediment-water management issues identified in the Integrator river basins characterisation reports...... 14 Figure 2. The DPSIR framework...... 16 Figure 3. A simplified representation of a soil-sediment-water system...... 17 Figure 4. From input variables to production level to pressures, an example for an arable farm...... 19 Figure 5. Use of the DPSIR components in cost-effectiveness and cost-benefit analysis...... 20 Figure 6: Location of the Geer basin in the Meuse river basin (map from IMC, 2005)...... 25 Figure 7. Land use (from DGRNE, 2005) ...... 27 Figure 8. Crops and pastures evolution from 1997 to 2005 on the Geer basin (Source : Arlon department of the University of Liege)...... 27 Figure 9. Spatial trend distribution in the Geer basin (From Batlle et al., 2005) ...... 28 Figure 10. Water abstraction in the Meuse groundwater bodies of the Walloon region (Data source: HGUlg; DGRNE, 2005)...... 29 Figure 11. Abstration of groundwater for drinking water production (Data source : HGUlg)...... 29 Figure 12. Wells and galleries in the Geer basin (based on maps from DGRNE, 2005 ; Orban et al., 2006) ...... 30 Figure 13. Abstration of groundwater by types of industry (Data source : HGUlg) ...... 31 Figure 14. Estimated parameters for domestic water consumption...... 31 Figure 15. Conceptual model of the Geer case study...... 32 Figure 16. Nitrate concentration trend of the main water abstraction points of the Hesbaye aquifer (Data source : HGULg)...... 35 Figure 17. Relationship between status indicator and damage ...... 36 Figure 18. Three levels of precision for the conceptual model of the Geer case study...... 40 Figure 19. Location of the Kempen area and the Dommel catchment as part of the Meuse River Basin... 44 Figure 20. Localisation of the industrial activities in the Kempen Area (source: OVAM) ...... 45 Figure 21. The pressure of industrial pollution on soil-sediment-water system (source: OVAM, 2006)...... 48 Figure 22. Cd concentration in the Kempen Area (source: OVAM, 2006) ...... 49 Figure 23. Concentration of Cd and Zn in some vegetables and crops in Limburg (in mg/kg) ...... 50 Figure 24. Trend of Cd concentration in the surface water in two sub-catchements of the Kempen area (source: van der Grift 2004)...... 54 Figure 25. Potential technical remediation measures and costs...... 57 Figure 26. Data and information needs and availability...... 58 Figure 27 Location of the Ebro river basin in Spain. Total dissolved salts exported from river basins to the sea in tons per square kilometer per year for different continents and Ebro (Data source: Meybeck, 1979) ...... 61 Figure 28 Conductivity in groundwaters in the Ebro basin (source: www.chebro.es) ...... 64 Figure 29. Xerosols among soil types in the Ebro basin: Xerosols are in blue (others: cambisols in brown, vertisols in dark pink) (source: EEA, soil map of Europe, 2005) ...... 65 Figure 30. Irrigated areas in the Ebro basin (in grey), 783,900 ha in total (source: CHE, 2005) ...... 66 Figure 31. Importance of large irrigation systems in the Ebro basin : 58% of the total irrigated area (source: www.chebro.es )...... 66 Figure 32. Localization of industries register in EPER with chlorides emissions for 2004 in the Ebro basin (Lila area) (source : ) ...... 70 Figure 33. Atmospheric deposits - Source : École des mines de Douai - Audition du 20 février 2002 dans qualité de l’eau en France ...... 71

11

Figure 34. Threshold for salinity parameters and their impact on ecosystems (Bremond 1979) ...... 72 Figure 35. Norms and guideline for salinity parameters in drinking water ...... 73 Figure 36. Cost evaluation of on site effect of salinisation in agriculture (cost is beard by farmers)...... 75 Figure 37. Adaptation of farmers practice with increasing salinity and according net income per hectare of crop...... 76 Figure 38. Table of effects for agriculture (Bremond, 1979) ...... 76 Figure 39. Relative yield losses for wheat, corn, alfalfa, tomatoes and barley according conductivity levels of irrigation water expressed in dS.m-1 ...... 77 Figure 40. Distribution of irrigated crops on the Tauste community...... 78 Figure 41. Requirements on water quality for several industries (Bremond 1979) ...... 79 Figure 42. Conceptual model for the Ebro case study...... 84 Figure 43. Hydrological boundaries of the Krsko kotlina aquifer...... 88 Figure 44. Key features of the Krsko kotlina aquifer...... 90 Figure 45. Past trends in nirate concentrations in the Krsko kotlina aquifer (1998-2004)...... 91 Figure 46. Yearly concentrations for atrazin and desetilatrazin in Krsko kotlina (2003-2004) ...... 92 Figure 47. Trends in concentrations of selected pesticides in Krsko kotlina (1997-2004) ...... 92 Figure 48. Estimated parameters for municipal water use(2005) ...... 94 Figure 49. Trends in people connected and drinking water abstraction for Drnovo and Brege wells (1997- 2004) ...... 94 Figure 50. Estimated parameters for Catez Spa water use (2005)...... 95 Figure 51. Trends in concentrations of selected pesticides in Krsko kotlina (1997-2004) ...... 95 Figure 52. Conceptual model for the Slovenian case study...... 101 Figure 53. Summary description of the agriculture sector for the Krsko kotlina aquifer case study...... 102 Figure 54. Summary description of the municipal (household) water service sector for the Krsko Kotlina aquifer case study ...... 102 Figure 55. Summary description of the disconnected household sector for the Krsko Kotlina aquifer case study...... 103 Figure 56. Summary description of the thermal tourism sector for the Krsko Kotlina aquifer case study . 103 Figure 57. Estimated parameters for municipal water use(2005) ...... 105 Figure 58. The Meuse river basin...... 108 Figure 59. Relevant branches of the Meuse...... 110 Figure 60. Net water abstraction for each branch (m3/s) (Source: Raadgever, 2004)...... 112 Figure 61. Net water abstraction for each sector (m3/s) (Source: Raadgever, 2004)...... 112 Figure 62. Conceptual model of the Meuse related to water use...... 113 Figure 63. Driving forces for industry and their effects ...... 113 Figure 64 Driving forces for agriculture and their effects ...... 114 Figure 65. Driving forces for energy and their effects...... 114 Figure 66. Driving forces for drinking water and their effects...... 114 Figure 67. Knowledge needs and availability...... 115 Figure 68. Main socio-economic sub-systems considered in the conceptual models of the INTEGRATOR case studies...... 117

12

1. Introduction

Worldwide, river basins are under pressure of economic activities that affect their chemical and ecological status and deplete available soil-sediment-water resources. Because water is both an input to many production processes and a sink for pollution and wastewater, there is a two-way interaction between economic activity and river basin resources that needs to be understood in order to support policy decisions dealing with both economic sectors and environmental issues.

The wide range of economic activities and the hydrological complexity of many river basins, both in terms of the functioning of the soil-sediment-water system and of the links between quality and quantity and economic activities, make the integrated analysis and modelling of river basins difficult and challenging – in particular when policy support is one of the aims of such analysis and modelling. A first step in such integrated analyses and modelling is the development of integrated conceptual models expressing the relation between economic actors and their use of river basin resources.

The development of integrated conceptual models is the focus of the present report – building in particular on the framework of the generic conceptual model developed in the INTEGRATOR 1 sub-project of AquaTerra (Herivaux et al. , 2005). The objective of this report is to investigate the development of integrated conceptual models with main focus on economic activities related to the soil-sediment-water system. Such integrated conceptual models will need to capture both economic activities that impact soils, sediments and water resources and those that depend on these resources – thus considering the cause-effect chains between:

• Water quality/water status and economic sector activities,

• Economic sectors’ activities and water status/water quality, and

• External drivers and global changes that might impact on both the economic sectors and on the soil-sediment-water system.

The report presents the development of conceptual integrated models for a series of case studies, following a series of simple steps proposed for characterising the different elements of these integrated conceptual models. The case studies selected reflect a range of management issues (Figure 1) identified in the INTEGRATOR river basin characterisation reports (Bouzit et al. , 2005; Strosser et al. , 2005; Maring et al. , 2005; Chapman et al. , 2005). They include:

• The Geer Catchment (Meuse, Walloon region) – diffuse nitrate pollution in groundwater;

• The Kempen area (Meuse, Flanders and Netherlands) – soil contamination by heavy metals;

• The central Ebro (Ebro, Spain) – soil and surface water degradation due to high salinity;

• The Krsko kotlina aquifer (Danube, Slovenia) – groundwater pollution by nitrates and pesticides;

• The Meuse river basin (Flanders & Netherlands transboundary region) – water quantity (low flows, high flows) problems.

13

Figure 1. Main soil-sediment-water management issues identified in the Integrator river basins characterisation reports.

The report is structured as follows. In section 2, the overall framework and methodological issues are presented and discussed. This section proposes a series of simple steps for developing an integrated conceptual model that are then applied to the case studies – the results of these applications being presented in Sections 3 to 7. Section 8 summarises the different results and conclusions, stressing in particular areas where follow-up activities might be proposed in the context of I3 activities of INTEGRATOR.

14

2. Methodology and economic concepts

2.1. THE OVERALL FRAMEWORK

The development of integrated conceptual models is based on the overall framework proposed in the INTEGRATOR 1 sub-project of AquaTerra (Herivaux et al. , 2005) that structures a given policy-relevant system (in our case the soil-sediment-water system) into different components: Driving forces, Pressures, State, Impacts and Responses. Figure 2 presents this so-called DPSIR framework in it general form, where:

• Driving forces are the underlying causes of environmental pressures. Examples are agricultural production and farming, energy production, industrial activities, tourism…. These Driving forces are themselves influenced by a series of external drivers and/or global changes such as sector policies, climate change and institutional changes.

• Driving forces lead to pressures on the environment, for example water abstraction or the discharge of nutrients from agricultural soils to surface water and groundwater;

• Pressures in turn affect the state of the environment. This refers to the quality of the various environmental media (soil, groundwater and air for example) and their consequent ability to support the demands placed on them. For example, pollution of water bodies affects their ability to act as a source of drinking water. Global changes can directly affect pressures, e.g. changing climatic conditions that influence leaching to water;

• Changes in the state of the system may have social, economic, and/or ecological impacts on human health, ecosystems, biodiversity, amenity value, financial value and so on. Here also, climate change can have a direct impact on the state, for example changes in temperature may to changes in the aquatic ecosystem;

• From the assessment of impacts, or in application to the precautionary principle, decision-makers have to determine appropriate responses , in order to mitigate impacts or prevent future impacts.

It is important to stress that responses can target different parts of the soil-sediment-water system. In the case of driving forces the response can be a change in agriculture policy resulting in new prices for agricultural output or fertilisers. Pressures from municipal wastewater could be addressed by building a wastewater treatment plant reduces pressures. The state of the aquatic environment could be improved by the building of artificial wetlands to help control water quality and impacts could be reduced by supporting the installation of denitrification plants for ensuring good quality drinking water, or providing drugs that might deal with possible illness).

15

Figure 2. The DPSIR framework

2.2. BUILDING INTEGRATED CONCEPTUAL MODELS

To understand the relations between the different components of the DPSIR framework and to build integrated models that can help to support policy decisions, a wide range of socio- economic, decisional and bio-physical processes need to be investigated. Integrated assessment can be defined as the interdisciplinary process of combining, interpreting and communicating knowledge in such a way that the entire cause– effect chain of a problem can be evaluated and thus provide useful information to decision makers (van Asselt et al. , 1996).

A key step in the development of integrated models is its conceptual phase. The end results of this phase include two main aspects:

• The identification of the different sub-systems of the whole soil-sediment-water system (from Driving Forces to Pressures to State to Impact) that need to be investigated and the understanding of the relationships between these sub-systems, and

• The understanding of the variables/factors that characterise each sub-system and which relationships need to be investigated and modelled.

These are further described and discussed in the following paragraphs.

2.2.1. Defining boundaries and sub-systems

The first task for the development of the conceptual model is the identification of the main sub-systems that compose the entire system and that will need to be investigated in order to support policy decision making, along with the boundaries of the system under investigation.

Defining the different sub-systems can start with the identification of the main actors and decision making processes that are both influenced by and influence the soil-sediment-water system. How actors’ decisions impact on the natural system can help to identify how to disaggregate the natural system into a limited number of sub-systems within the structure of the DPSI system, including the links between both the different sub-systems and the external (exogenous) factors (considered as constant for the policy question under investigation) and the different sub-systems.

16

Several issues relevant to the definition of the system’s boundaries and its sub-systems must be considered.

• The policy question or range of policy questions that need to be addressed influences both the boundaries and the sub-systems that need to be identified. For example, if the policy question requires an understanding of the markets for agricultural products, such markets will need to be considered as sub-systems. This stresses already that talking about conceptual models in general without reference to specific policy questions or a range of policy questions is neither useful nor relevant.

• The term “boundary” needs to be understood in its wide sense. A boundary does not reflect only hydrological boundaries that are usually considered in technical studies. Socio-economic issues and related units such as markets, social systems, institutional boundaries also need to be considered. Following on from the previous example, if markets for specific goods are pre-dominant in explaining changes in the soil-sediment-water system and if these markets are European markets, then the system might include other European actors active in these markets.

• In defining sub-systems, one needs to consider early on the types of responses that might be considered early on, as this will define the cause-effect chain/relationship that must be investigated in order to address specific policy responses. For example, if a possible policy response is the establishment of an environmental tax for solving nutrient pollution in surface water, one would need to understand (i) the impact such a tax will have on the decision making of the main economic sectors, (ii) the relationship between actors’ decisions and pressures, and finally (iii) how pressures influence the state of the water body (this last component may be separated into different sub-systems such as sub-soil, deep soil, groundwater, surface water and so on).

• The scale at which impacts might take place needs to be considered in defining the limits of the system under investigation.

The final product of this step is a simplified representation of the system under investigation that presents the different sub-systems inter-linked in a schematic manner (see Figure 3). This representation often becomes a powerful means of stimulating discussion and interaction on highly complex issues and responses.

Figure 3. A simplified representation of a soil-sediment-water system

17

Proportionality is a key issue when building an overall integrated system, as one need to decide how far to go in terms of the boundaries and level of details and disaggregation of the system in sub-systems. On one side, it is important that the main processes are well captured and differentiated. On the other side, it is important that the level of details does not become a constraint in itself keeping all complexity intact (while the representations aim at providing a simplified picture of the system relevant to policy discussions and modelling).

2.2.2. Capturing the functioning of the different sub-systems

The second task is to identify the inputs, characteristics/descriptive parameters and outputs for each sub-system, along with the main relationships that link these different variables.

For the sub-systems representing biophysical and natural processes, this task has often been done by compiling data from individual Aquaterra SP activities – often restricted to the selected biophysical processes investigated in details apart from COMPUTE which aims to develop models of the different biophysical processes and their relationship to global changes.

In the case of sub-systems that represent socio-economic components and decision-making processes, the identification of the different variables needs to be complemented by the identification of the overall objectives of the decision-making process or actor. In general, such decision-making models build on explicit assumptions on behaviour by firms and people grounded in microeconomic theory. Two basic assumptions are usually proposed (Mas-Colell et al. , 1995):

• Firms maximise profits: Given a vector of prices (i.e. firms are considered price- takers), and a production set (formed by technological constraints), the firm’s objective is to maximize its (expected) profits. The price-taking assumption is reasonable, given that we analyse production at catchments or basins level, whereas most products are traded at world market-level.

• People maximise utility: Given a vector of prices, and personal wealth level, people choose their most preferred consumption bundle as to maximise their (expected) utility.

For some actors, however, in particular those that are not from the private sector, both basic assumptions and proposed objectives might not apply. Additional objectives may include the delivery of basic services to a population or the protection of a protected natural area. A municipal water service operator, for example, will need to deliver drinking water of a given quality to its customers, and profit maximisation may not be its main objective (although cost- minimisation might be a constraint to its objective).

We can reasonably assume that based on given set of initial conditions - including prices, but also other conditions as will be shown later - people and firms choose a certain consumption and production level. In this decision they typically do not take into account adverse effects of their consumption and production on environmental quality, because there is no market for many aspects of environmental quality. The absence of a well defined market for environmental quality (often referred to as market failure) causes pollution levels to be higher than desired by society (Perman et al. , 2003). This notion of “over-pollution” and its causes are important to work within INTEGRATOR, because it clarifies why and how economic activities affect and are affected by the quality of the soil-sediment-water system in a river basin. It can be used to describe what drives production and consumption decisions and how the available quality and quantity of water affects profits of firms and utility of people. It also shows that the driving forces and pressures in the DPSIR model can be influenced by

18

responses when the right conditions of firms or people are targeted. These conditions will differ for different firms and different people.

As an example, here is a short list of variables and factors that might influence the production decision of an arable farm: (i) crop area, (ii) crop price, (iii) fertilizer input cost, (iv) machinery cost, (v) labour cost, (vi) irrigation cost, (vii) water availability, (viii) water quality, (ix) climate data, etc. The production level of this farm determines the pressures that it puts on the soil- sediment-water system, in the form of nutrient- and pesticide leaching for example. Its production level is determined by the maximisation of its profit function (F) where the conditions are variables of this function. Here, water is both an input to the production process as well as a sink for pollution. Figure 4 summarises how a sub-system can be characterised.

Figure 4. From input variables to production level to pressures, an example for an arable farm

Clearly, the level of complexity in identifying variables and relationships will not be the same for all the different sub-systems, as some might represent simple processes or be less important for the policy question identified. As understanding of the sub-systems functioning increases, new issues might be discovered that lead to proposed changes for the overall conceptual model.

2.3. FROM CONCEPTUAL MODELS TO SUPPORT TO DECISION MAKING

Conceptual models are not an end in themselves – but a basis for improved understanding of the system under investigation and for the development of computer based models integrating both technical and socio-economic aspects. These models can help to support decision making, in particular:

• By assessing the impact of global changes and identifying economic sectors that will be impacted negatively (and by how much). This impact assessment can then be used for justifying the need for action at different scales (from local to global);

• By providing relevant information for undertaking economic assessments of possible policies, projects and measures – for example cost-effectiveness analysis or cost- benefit analysis (see Box 1 for a summary of selected economic assessments).

19

Box 1 – Economic concepts and methods Economic analysis is often an explicit part of studies on integrated river basin management, mainly in two forms: cost-effectiveness analysis (CEA) and cost benefit analysis (CBA): CEA: CEA can be applied to evaluate a programme of measures in order to select the least-cost option. This approach is commonly used when (i) a specified objective has been established by policy (such as a pollution level to be achieved or a risk level considered as unacceptable) and is not subject to be tested, or (ii) the estimation of benefits is infeasible or surrounded by too much uncertainty (USEPA, 2003; Perman et al. , 2003). The main methodological steps of CEA are: (i) the development of a programme of measures that could be implemented to reduce a certain pressure on the soil-sediment-water system in a river basin, (ii) an assessment of a reference unit cost value for each measure, (iii) the planning and selection of the relevant scale for the implementation of measures, and (iv) an ex ante cost assessment of the implementation of the measures. Cost assessment of potential measures should include investment cost and recurring costs (operation and maintenance), direct and indirect costs. CBA: CBA can be applied to evaluate a programme of measures in ways that correct market failures (Perman et al. , 2003). This approach is commonly used when reliable estimates of both costs and benefits of the measures are available. CBA is used to select that measure that maximises the difference between its benefits and costs. Costs of environmental projects are mostly easily observed using market data. Benefits of environmental projects are usually assessed as the avoided damages. Damage may be considered here as the negative consequences of pressures on the soil-sediment-water system (in terms of quality or quantity). For the case of water pollution, damage may lead to negative impacts on a range of use and non-use values. Elements to be considered might include (i) costs incurred by drinking water utilities, (ii) loss of income for households that switch to bottled water; and (iii) loss of recreational value due to the deterioration of wetlands – losses that can be valued in monetary terms using specific methodologies (e.g. stated preference methods or revealed preference methods). CEA and CBA are methods for economic analysis that are useful in comparing and selecting from a programme of measures. These methods already have an important part to play in current policy development, such as the economic analysis required for the implementation of the Water Framework Directive, and CBA recommended by the French approach of contaminated land management.

Figure 5 presents the different components of the DPSIR framework that can be considered when selecting possible measures and undertaking a cost-effectiveness and/or cost-benefit analysis. For the purpose of policy analysis, it is necessary to identify at least two scenarios in the future – one scenario representing the base case with no policy action (which in turn might lead to deterioration of the natural environment with negative impacts on uses/the natural ecosystem) and the second scenario representing the possible policy response that will influence different components of the system under consideration.

Figure 5. Use of the DPSIR components in cost-effectiveness and cost-benefit analysis

20

The main steps to be carried out for supporting the policy would then include the following:

a. Identify the reference/base case scenario (“without policy”). This scenario should (i) identify the main factors DA which could affect the quality or quantity of the soil- sediment-system, (ii) assess the main pressures PA exerted on the system, taking into account global change (climatic change, politic change, etc…), (iii) assess how the current quality and quantity will change ( SA) using for example Aquaterra physical models/results if available and finally (iv) describe the main economic sectors that would be affected by the potential natural system degradation and the related economic impacts IA.

b. Identify and describe potential responses, i.e. the “with policy” scenario(s). The objective is to identify potential measures that aim to limit the degradation of the soil- sediment-water system in SA and to assess the costs of their implementation. The same analysis as in the reference scenario should also be done in order to assess (i) the main driving factors DA, (ii) their related pressures, (iii) the change in the current quality and quantity of the system SB after the measure(s) implementation and (iv) related economic impacts IB.

c. Perform cost-effectiveness analysis and/or cost-benefit analysis. Comparison of the quality and quantity of the natural system between the scenario with or without policy (∆S = S B - S A) allows to assess the effect of the proposed measure(s) and may be integrated in a cost-effectiveness analysis. The comparison of the economic impacts (∆I = I B - I A) between the two scenarios would support the assessment of the benefits of the proposed measure(s)/policy and thus would form the basis of a cost-benefit analysis.

d. Undertake a sensitivity analysis – assessing how results of the cost-effectiveness or cost-benefit analysis would change if the values of some key factors/parameters for the different components (D, P, S and I) would be modified by given percentages. In addition to identifying the factors that mostly explain the sensitivity of the end results, the analysis would identify both the parts of the system/analysis that are robust/do not change within a certain range of values – and also the components of the proposed policies that will be beneficial whatever the circumstances.

These steps and the building of computer-based models that integrate socio-economic and technical aspects of the soil-sediment-water system are not dealt with in the present deliverable. They have been summarized here, however, to clarify the overall policy support context under which conceptual models will be developed for the different case studies. They will be part of the follow-up activities proposed under activity I3 of INTEGRATOR – building in particular on the results of other technical work within Aquaterra that investigates the (bio-) physical components of the soil-sediment-water system and on the “societal system knowledge’ (socio-economic, juridical and governance issues) partly addressed by INTEGRATOR and EUPOL SP.

2.4. CASE STUDIES APPLICATION

The two steps described above have been applied to the different case study areas (i.e. the Geer Catchment, the Kempen area, the central Ebro basin, the Krsko aquifer and the Meuse river basin) to identify the main components of integrated conceptual models for the soil- sediment-water systems of these areas. The results of these applications are presented in the following chapters of the report.

The development of the conceptual models in each case study area was based on:

21

• A review of literature to identify both technical and socio-economic issues was derived from research reports produced by administrative bodies, universities and other research institutes and information from existing databases. The recent Article 5 reports, developed by Member States for the implementation of the Water Framework Directive, proved useful in this context;

• Interaction with local experts – during workshops organised through the INTEGRATOR 1 work package of Aquaterra, during bilateral discussions on specific issues;

• Interaction with experts from other (technical) SPs of Aquaterra for case studies areas where parallel activities from other SPs are implemented. This was particularly fruitful in the case of the Geer catchment and Kempen area.

In addition to building the conceptual model, each case study addressed the issue of data and knowledge availability. The existing information and knowledge on the functioning of the soil-sediment-water system in each area was compared with the information and knowledge that would be required for investigating the different components, variables and relationships identified in the integrated conceptual model. In reviewing existing information and knowledge, priority was given to information and knowledge from (i) the Aquaterra project developed in the case study area and (ii) from the Aquaterra project developed in other case study areas but potentially relevant to the issues at stake in this case study. This has helped to identify current gaps in information and knowledge and provides the basis of an assessment of the relative effort one might face if an integrated computer-based model integrating economic and decision-making processes would need to be built for the case study considered.

Note: The content and analysis level of the conceptual models developed for each case study may vary from one to another chapter, depending on (i) the nature of the selected environmental issue and (ii) the availability of data.

REFERENCES

Bouzit, M., C. Hérivaux, et al. (2005). A case study report on the Meuse by BRGM in relation with EUPOL and BASIN. Deliverable I1.1c of the Aquaterra project.,Montpellier, BRGM: 64.

Chapman, A. and P. Bardos (2005). Case study on the Ebro River Basin (characterisation). Deliverable I1.1f of the Aquaterra project., R3 Environmental Technology, Department of Plant Science, University of Reading, UK.

Hérivaux, C., S. Loubier, et al. (2005). Generic conceptual representation of river basin and methodological guidelines to construct such a representation with a participatory approach. Deliverable I1.3 from Aquaterra project. May 2005. 52p. BRGM, Montpellier.

Maring, L., L. Gerrits, et al. (2005). Elbe River Basin characteristics. Soil, Sediment and Water in the Elbe River Basin. Deliverable I1.1d of the Aquaterra project., The Netherlands, TNO.

Mas-Colell, A., M. D. Whinston, and J. R. Green (1995). Microeconomic theory. Oxford University Press, New York.

Perman, R., Y. Ma, J. McGilvray, and M. Common (2003). Natural resource and environmental economics. Pearson Education Limited, Harlow.

Strosser, P., E. Ansink, et al. (2005). Danube River Basin Characterisation. ). Deliverable I1.1e of the Aquaterra project., Wageningen, WUR, Acteon.

22

USEPA (2003). Integrating Ecological Risk Assessment and Economic Analysis in Watersheds: A Conceptual Approach and Three Case Studies, Prepared by the National Center for Environmental Assessment, Cincinnati, OH. EPA/600/R-03/140R. Available from: National Technical Information Service, Springfield, VA, PB2004-101634; and .

Van Asselt, M. & Rotmans, J. (1996). Uncertainty in perspective. Global Environmental Change , 6(2), 121-157.

23

3. The Hesbaye aquifer (Meuse, Walloon region): nitrate pollution in groundwater

For further information, please contact Cécile Hérivaux (BRGM) – [email protected]

3.1. INTRODUCTION – CONTEXT AND AIM OF THE STUDY

3.1.1. General context - Nitrate contamination of aquifers

Diffuse agricultural pollution is a major groundwater management issue in the Meuse River Basin (IMC, 2005a). The overall quality of the groundwater system becomes degraded from the upper to the lower stretch of the Meuse River Basin (Bouzit et al. , 2005). Results of water quality monitoring show that 100% of the measured concentrations in the French part are below 50 mg/l (AERM, 2004). Whereas 6% of the measurements in the Walloon stretch and 20% of the average concentrations in the German aquifers exceed 50 mg/l 1, more than 50% of the shallowest aquifers in the Netherlands are contaminated with concentrations that can reach 100 mg/l (DGRNE, 2005; RBO-Maas, 2004). Historic trend analyses show a general increase in groundwater nitrate concentration. Due to the already high nitrogen contents in the soil, 18% of the Walloon Region, 20% of the French stretch of the Meuse basin and the entire area of the Basin in the Netherlands are classified as vulnerable areas under the Council Directive 91/676/EEC 2 (DGRNE, 2005; AERM, 2004; NL-Water, 2004). It must be noted that concentrations of nitrates in groundwater have increased in all European countries during the last decade (DGRNE, 2005).

Diffuse pollution of aquifers is a subject of high importance in the Meuse River Basin, as groundwater is the main drinking water resource: about 1 billion m 3 are used every year in the Meuse River Basin for drinking water production, including 725 million m 3 abstracted from groundwater resources (IMC, 2005b). High concentrations of nitrate in groundwater may thus be a threat to human health. The European Directive 98/83/EC sets a limit for the nitrate concentration in drinking water of 50 mg/l. However, given that the transfer time of the water between the surface and the aquifers is sometimes in the order of years to decades, the groundwater quality compliance with European drinking water standards may not be ensured everywhere. Economic damage to the drinking water sector may thus occur. High concentrations of nitrate in alluvial groundwater may also lead to the eutrophication of water bodies through transfers between groundwater and surface water.

In order to recommend relevant policies, a proactive management approach is needed. This should be based on the natural scientific understanding of the soil and water system on the one hand and on the socio-economic understanding of the functions of this system for various land and water uses on the other hand (Halm et al. , 2005). Preventive measures should be taken, leading to a decrease in the economic damage by shortening the time of groundwater contamination.

1 From « Dokumentation der wasserwirtschaflichen Grundlagen (Bestandaufnahme NRW) 2004 » of Schwalm, Niers and Roer available at www.rur.nrw.de, www.niers.nrw.de, and www.schwalm.nrw.de. 2 Council Directive 91/676/EEC of 12 December 1991 concerning the protection of water against pollution caused by nitrates from agricultural sources.

24

3.1.2. The Geer basin / Hesbaye aquifer – general characteristics

The Geer basin (480 km²), is located within the Meuse River Basin, in the eastern part of Belgium, North-West of Liege (Figure 6). A very important groundwater resource is located in this basin: the Hesbaye aquifer. The aquifer is characterized by a chalky layer of several meters (from 10 to 70m) and surmounted by a thick eolian loess deposit (Orban et al. , 2006). The aquifer supplies drinking water to about 350,000 inhabitants in Liege and its suburbs. Approximately 22 million m 3 are abstracted annually by galleries and pumping wells.

Due to its relatively flat topography and to the loess deposits, the Geer basin is predominantly agricultural: crops and pastures cover 83% of the catchment area. The remaining area is divided between housing (10%), forest (2.5%) and other uses (4%) (Orban et al. , 2006). The region is intensively cultivated. Presently, the mean nitrate concentration in groundwater (40 mg/l) is close to the drinking water limit. The Hesbaye aquifer has been identified as the groundwater body most affected by agricultural pressures in the Walloon Region (DGRNE, 2005). Future groundwater quality trend estimates show that the mean nitrate concentration of the water body will exceed the drinking water limit in the coming years. The main groundwater user – the drinking water sector – is therefore very concerned with this contamination issue, especially since there is no sustainable alternative resource identified at the present time for the drinking water supply of Liege and its suburbs.

Figure 6: Location of the Geer basin in the Meuse river basin (map from IMC, 2005)

3.1.3. Overall objectives of the case study

One of the major issues at stake in the Geer basin is to estimate if groundwater quality will comply with European drinking water standards in the coming decades and thus avoid the need for the implementation of costly treatment measures by the affected sectors. Even if preventative actions (commonly recommended) are undertaken, their effectiveness - in terms of decreasing groundwater nitrate concentration - is uncertain. No direct link has been established between the implementation of preventive measures and their benefits (avoided damage). For this purpose, an integrated approach including a range of socio-economic, decisional and bio-physical processes needed to be developed. Therefore the main aims of this case study was to illustrate how the DPSIR framework may be used to assess the potential environmental and economic impacts related to the evolution of nitrate

25

concentration in the Hesbaye aquifer and the potential benefits of the implementation of preventative actions.

During 2005, several meetings were organised by the Brgm team to better understand the different sub-systems that need to be investigated to build a conceptual model of the system under study. These meetings involved the Hydrogeology Group of the University of Liege (HGULg) 3, the Arlon department of the University of Liege 4, the University of Gembloux (FUSAGx) 5 and the main drinking water company located in the Geer basin (CILE) 6. These various meetings and discussions led to (i) the characterisation of the different components of the DPSIR framework and their relationships, (ii) a better identification of the local stakeholders’ needs with respect to the nitrate issue and (iii) the identification of the existing or lacking information and knowledge.

This chapter presents the main results of these investigations. It is structured as follows:

- Identification and analysis of the different sub-systems of the entire soil-sediment- water system regarding groundwater nitrate contamination (3.2);

- Understanding of the factors that characterise each sub-system and understanding of the relationships between them (3.3).

3.2. ANALYSING DPSI IN THE GEER BASIN

3.2.1. Economic activities exerting pressures on the Hesbaye aquifer (Drivers and Pressures)

Agriculture is a dominant activity in the Geer basin (DGRNE, 2005). Crops and pastures cover 83% of the total basin surface. It represents the main source of nitrate loads in groundwater, followed by the domestic effluents. According to Dautrebande et al. (2004), the respective contributions of diffuse agricultural and dispersed domestic sources in the Geer basin in relation to nitrogen losses by leaching near groundwater are 88% and 12% respectively. This chapter will only focus on the diffuse pressure exerted on groundwater by nitrate (NO 3) from agricultural activity.

3 The Hydrogeology Group of the University of Liège (HGULg) is involved, for years, in different project to study this aquifer. In particular, different groundwater flow and solute transport models at the local or at the basin scale have been developed. A complete description of the Geer basin, of the available datasets and a synthesis of the previous studies can be found in the Deliverable R3.16. The groundwater flow and solute transport model developed by HGULg in the framework of the Aquaterra can be used to assess the relation load of nitrogen – nitrate concentration in the groundwater. 4 Water and Environment department ( http://www.dsge.ulg.ac.be/index.php?pg=100&unite=11) 5The University of Gembloux ( http://www.fsagx.ac.be/fac/en/default.asp ) is involved in the development and the application of the EPIC-Grid model for most watersheds in the Walloon Region in the framework of the PIRENE project (Water and Environment Integrated research project of the Walloon Region). 6 http://www.cile.be/

26

Figure 7. Land use (from DGRNE, 2005)

Farms located in the Geer basin mainly specialise in field crops and cattle (dairying and fattening). In 2005 cereals and industrial crops (mainly sugar beets, flax and chicory) represent the main part of the agricultural land use (41% and 29% respectively). Pastures use about 14% of agricultural land. Figures of the evolution of agricultural land use from 1997 to 2005 show a decrease in pasture area (-11%), cereals (-91%) and sugar beet (-16%), while other industrial and horticultural crops area increased (flax: +48%, chicory: +105%, horticulture: +96%) during the same period (Figure 8).

Figure 8. Crops and pastures evolution from 1997 to 2005 on the Geer basin (Source : Arlon department of the University of Liege)

Diffuse agricultural pressures on groundwater have been assessed with the EPIC-grid model developed by the University of Gembloux for the Walloon Region in the framework of the PIRENE project (Dautrebande et al. , 2004). Results show a mean NO 3 concentration in leaching water (at a depth of 1.5 m) of 57.1 mg /l. More than 73% of the groundwater body surface is affected by NO 3 concentration in leaching waters exceeding 50 mg/l.

27

3.2.2. Nitrate concentration in the Hesbaye aquifer (State)

According to DGRNE (2005), the Hesbaye aquifer is the most affected groundwater body by agricultural pressures in the Walloon Region. The Hesbaye aquifer has been classified as a vulnerable area. Given to the results of the quality monitoring network (21 points), more than a third of the monitoring points exceed 40 mg/l. However, spatial variations in nitrate contents in the Hesbaye aquifer have been observed (Batlle et al. , 2005). Nitrates are almost absent in the North of the basin (confined conditions of the aquifer) while concentrations are close to the drinking limit in the South (unconfined conditions) 7.

Figure 9. Spatial trend distribution in the Geer basin (From Batlle et al., 2005)

Historic trends in nitrate concentration in the Hesbaye groundwater (1950-2003) were studied by the Hydrogeology group of the University of Liège (HGUlg) using mainly nitrate concentration time series from the Nitrate Survey Network (NSN) established by the Walloon Region Government (Batlle et al. , 2005). The results show a general upward trend (Figure 9), especially in the Southern part of the aquifer where nitrate concentrations have risen annually at an average rate of 1 mg/l from 1960. In the Northern part nitrate has not been detected or at very low concentration.

3.2.3. Economic activities potentially affected by the degradation of groundwater quality (Impacts)

The Hesbaye aquifer is one of the most exploited groundwater bodies in the Walloon Region, with about 24 million m 3 abstracted in 2003 8 (Figure 10). The main water user is the drinking water sector (85%), followed by the industrial sector (14%, mainly for cooling), then agriculture and services (1%). The increase in nitrate contamination could thus be a threat for these economic sectors in the coming decades.

7 According to Batlle et al. (2005), there are two main assumptions for the absence of nitrate in the Northern part of the aquifer: (i) the occurrence of denitrification processes in the confined part of the aquifer or (ii) the occurrence of very old, still uncontaminated groundwater. 8 Data on water abstraction were obtained for years 2002 and 2003 (source : Hydrogeology Unit – University of Liège.

28

Figure 10. Water abstraction in the Meuse groundwater bodies of the Walloon region (Data source: HGUlg; DGRNE, 2005)

Drinking water sector

Three companies exploit the Hesbaye aquifer for drinking water production: (i) the Compagnie Intercommunale Liégeoise des Eaux (CILE); (ii) the Société Wallonne de distribution des Eaux (SWDE); (iii) the Vlaamse Maatschappij voor Water-voorziening (VMW). The abstracted volumes are given in Figure 11. The locations of wells and galleries are shown in Figure 12.

Drinking water company Abstracted volume in 2003 (million m3) CILE 16.7 (78%) SWDE 3.0 (14%) VMW 1.6 (8%) Total drinking water sector 21.3 (100%)

Figure 11. Abstration of groundwater for drinking water production (Data source : HGUlg)

The CILE

The production and distribution of drinking water in Liege have been the responsibility of the CILE since 1979. A total network of 48 km of galleries oriented ENE-WSW 9 exploit the Hesbaye aquifer, allowing a production of approximately 17 million m 3/ year (45,000m 3/day on average).

These galleries, dug in chalk between 30 and 60 meters of depth, are subdivided in two networks: the northern gallery and the southern gallery. The southern gallery uses a gravity feed system and a series of underground aqueducts to supply the Hollogne and Ans reservoirs. The total volume abstracted in these reservoirs is about 16 million m3/ year, making it possible to supply approximately 75,000 households in Liege and its neighbouring

9 Perpendicularly within the meaning of underground water run-off.

29

communities. Three wells ( Jeneffe , Waroux , Lantin ) pump water directly in the southern galleries in order to feed the villages of the Geer basin (approximately 1 million m 3/ year).

Figure 12. Wells and galleries in the Geer basin (based on maps from DGRNE, 2005 ; Orban et al., 2006)

The water collected in the northern galleries is raised by three pumping stations ( Kemexhe , Puits regulating and Juprelle ) before being discharged via underground aqueducts into the southern gallery. Water from northern galleries is mainly used when the production of the southern galleries is insufficient or when the nitrate concentration is too high (dilution of water).

The SWDE and VMW

The SWDE collects groundwater through 8 wells located in the northern part of the Hesbaye aquifer. In 2003, the abstracted volume was about 3 million m 3. Waremme-Bovenistier (4 wells) and Remicourt exploit the aquifer in the free part of the aquifer (approximately 2.5 million m 3 in 2003). Along the Geer River, some wells belonging to SWDE ( Eben-Emael and Bas-Slins ) and VMW ( Wonck and Roclange-sur-Geer ) exploit the semi-captive part of the aquifer (approximately 500,000 m3 in 2003).

The industrial sector

The industrial sector may also be affected by deterioration in groundwater quality, depending on the nature of the activity. According to Rinaudo et al. (2004), three principal groups of industrial activities can be distinguished: (i) activities non sensitive to the nitrate concentration of the water resource used (e.g. paper mills and heavy industry such as steelworks); (ii) activities sensitive to the nitrate concentration such as the sectors electronics, pharmaceutical or chemical sectors, for which the industrial processes require a very pure water; (iii) the agro-food sector, where water is a basic ingredient and must correspond, at least, to drinking water requirements.

A first analysis of the abstracted water quantity gives the following results (Figure 13):

30

Branch of industry Abstracted volume in 2003 (million m3) Cooling 1.36 (53%) Agro-food production 0.90 (35%) Cleaning services 0.30 (11%) Others 0.03 (<1%) Total industrial sector 2.59 (100%)

Figure 13. Abstration of groundwater by types of industry (Data source : HGUlg)

Households

It is estimated that approximately 150,000 households are supplied with drinking water coming from the Hesbaye aquifer, representing a population of approximately 350,000 inhabitants (Figure 14). Degradation of groundwater quality may affect households through an increase in water prices. Households may also develop alternative options to improve the quality of their drinking water such as the purchase of individual purification systems or an increase of bottled water consumption, for example.

People connected to drinking water produced from the Hesbaye aquifer 350,000 Estimated yearly population growth [1] 0,27% Annual groundwater abstraction for drinking water production [2] 21.3 million m 3 Annual drinking water consumption [3] 17.4 million m 3 Mean annual tap water consumption per inhabitant in 2004 [4] 50 m 3 Mean annual bottled water consumption per inhabitant in 2001 [5] 127 litre Mean domestic tap water price [6] 2.65 €/ m 3 [1] Source: INS, http://www.statbel.fgov.be/figures/d23_fr.asp [2] in 2003 (source: HGUlg) [3] estimated with a network yield: 83% (source CILE, 2004) [4] in 2004 (source CILE, 2004) [5] in 2001 (source: Aquawal http://www.aquawal.be/xml/fiche-IDC-179-IDD-333-.html ) [6] in 2006 (Source: CILE)

Figure 14. Estimated parameters for domestic water consumption

3.2.4. Integrated Conceptual model

The integrated conceptual model for the Geer basin case study combining the different elements considered for DPSI is presented in the following synthesis figure (Figure 15).

31

Figure 15. Conceptual model of the Geer case study

This scheme represents the main components of the DPSI conceptual model applied to groundwater nitrate contamination. It should be noted that a specific economic sector considered here as potentially impacted could also be a driver for another soil-sediment- water management issue. For instance the drinking water sector may be affected by contaminated groundwater but at the same time it could also directly affect the groundwater system in terms of water quantity. The industrial sector may also exert pressures and affect groundwater quality by discharge of dangerous and toxic substances that may ultimately result in groundwater contamination.

3.3. CAPTURING THE FUNCTIONING AND RELATIONSHIPS BETWEEN THE DIFFERENT SUB SYSTEMS

The implementation of the conceptual model aims to analyse the consequences of changes in drivers on the degradation of groundwater resources and on the economic impact that could affect specific sectors. To perform this analysis, we need (i) to understand the factors influencing the agricultural activities exerting pressures on groundwater (from Drivers to Pressures), (ii) to relate the change in agricultural practices to the evolution of the nitrate concentration in the groundwater (from Pressures to State) and (iii) to understand the adaptation of potentially affected sectors to a change in groundwater nitrate concentration (from State to Impacts).

3.3.1. Main factors influencing drivers and pressures on groundwater resource (from Drivers to Pressures)

The need to assess change in agricultural land use and farm practices

To assess the future evolution of groundwater quality we need to consider not only actual agricultural land use and practices but also historic ones (considering that the transfer time of nitrate between soil and groundwater may vary from 10 to 70 years) and future ones (how agricultural land use and practices will evolve in the coming years according to current and future agricultural and environmental policies?). Historic and actual agricultural practices data on the Geer basin already exist and have been collected by Dautrebande et al. (2004). On the other hand there is a need for tools to understand how agricultural activities (and related nitrate pressures) may change in the coming years.

32

A wide range of economic modelling tools have been developed in Europe since the 90s to analyse the economic and environmental effects of national policies aimed at reducing diffuse nitrate pollution (quotas, taxes or incentives) 10 . Economic modelling may be developed and applied from the farm scale to the country scale, depending on the aims of the model, the data available and their precision.

The main components to be investigated to understand the farmers’ behaviour and to build a conceptual model for the Geer case study may be summarized and simplified as follows. NO3 concentration in leaching waters depends on (i) crop surface area; (ii) agricultural practices and (iii) meteorological conditions. If we consider distribution of crop surfaces and agricultural practices as decision variables for the farmers, these variables are dependent on various factors such as crop prices, crop yields, available labour forces, machinery, energy prices, fertiliser prices, obligations or incentives (taxes, subsidies) to undertake better agri- environmental practices. External drivers may also be considered, including change in agricultural markets and policies (CAP reform, WTO negotiations…); change in environmental policy; climatic change and change in energy policy.

Agri-environmental policies

The following points outline recent agri-environmental policies related to the agricultural use of nitrate:

• Since the Hesbaye aquifer was classified as a vulnerable area in 1994, specific regulations have been developed in the Walloon Region program for a sustainable use of nitrogen in agriculture (PGDA) 11 . This consists of a program of measures concerning (i) maximum permissible organic nitrogen fertilisation; (ii) maximum permissible in total (mineral + organic) nitrogen fertilisation; (iii) specific conditions including prohibition of fertilisation during different time periods of the year; (iv) specific conditions for manure storage facilities.

• The implementation of agri-environmental incentive schemes applied to the Walloon Region 12 should also be assessed in the Geer basin. For instance, two agri- environmental measures aiming at reducing nitrate diffuse pollution are proposed in the Walloonian agri-environmental program of measures: (i) growing winter crops to provide soil cover in winter, to capture remaining nitrate in the soil and to limit nitrogen leaching and (ii) reduction of fertiliser input on cereals.

• Potential measures related to the establishment of Water Protection Areas in the Geer basin could also be assessed.

The actual current (and future) implementation of these measures by the farmers of the Geer basin could be the first aim of the development of a simplified economic model. The effects of these measures on the agricultural land use and practices could then be related to any changes in nitrate pressures to the aquifer.

10 For a complete literature review, refer to Loubier (2004). 11 The “Programme Wallon de gestion durable de l’azote en agriculture » (PGDA) is the Walloon application of the Nitrate Directive. For more information, please refer to http://www.nitrawal.be/pdf/pgda_resume_fr.pdf 12 Development of a national agri-environmental program of measures as an application of the European Rural Development Regulation (Council Regulation (EC) No 1257/1999 of 17 May 1999). For more information, please refer to RW (2006)

33

Simulating NO3 pressures in the coming decades

Box 2. Nitrate pressure on the groundwater resource (Source: HGUlg)

There is no direct relationship between the load of nitrogen on the crops and the nitrate concentration leaching to groundwater. Different factors can affect the fate of nitrogen spread on the land such as the meteorological conditions, the kind of crop and the crop rotation. Two kinds of approach can be used to estimate the nitrate fluxes to the groundwater: (1) a soil model approach or (2) an empirical approach based on statistics. These nitrate fluxes will be used as an input for the groundwater model.

The Soil model EPICgrid

The risk of groundwater nitrate pollution from environmental pressures on soil was evaluated for most watersheds in the Walloon region by the semi-distributed model EPICgrid (Dautrebande et al. , 2004) as part of the PIRENE project. At a resolution of 1 km², the model simulated crop growth, agricultural practices and different water and mass fluxes. The simulated fluxes included direct runoff, percolation, groundwater recharge, subsurface lateral flows, real evapotranspiration, nitrate fluxes. The model is physically based, without calibration. The model also simulates the transfer of water and nitrate through the unsaturated zone. In the framework of the PIRENE project, water and nitrate fluxes to the groundwater were computed at the mean groundwater level depth. Based on historical meteorological data and agricultural statistics, a simulation was performed for the period 1970-2000.

The empirical approach

On the basis of land use maps (for example, the Corine project) and on agricultural statistics (published for example by the Agricultural Center of Economics or the National Institute of Statistics), it is possible estimate the temporal evolution of the load to crops by agricultural region. Based on simplifying assumptions, it is the possible to estimate the temporal evolution of the mean nitrate concentration in the water fluxes beneath the crops.

3.3.2. Relationships between change in agricultural practices and evolution of nitrate concentration in groundwater (from Pressures to State)

Unfortunately, the load of nitrogen applied to the crops can not be directly linked to the nitrate concentration in a particular point within the basin. Statistical trend analysis may be used in a first approach to assess future evolution in groundwater concentration, but this method is not adapted to take into account various possible changes in drivers and pressures. The groundwater flow and solute transport model developed by HGULg in Aquaterra could be used to assess the relationship (if any can be established) between nitrogen loading and nitrate concentration in groundwater.

The use of statistical trend analysis

Box 3. Statistic trend analysis (Source: HGUlg)

In the framework of the workpackage TREND2, the Hydrogeology Group of the University of Liège has used statistical tools to study the temporal evolution of the groundwater nitrate contamination (Batlle, 2005). The analysis shows a general upward trend; especially in the Southern part of the aquifer where nitrate concentrations have risen at an average rate of 1 mg/l per year from 1960. In the Northern part, nitrate has either not been detected or detected at very low concentrations.

The results, provided by HGUlg, enable an estimate of when the drinking water limit will be exceeded in each point. Except for the points located in the Northern part of the aquifer the limit will be exceeded everywhere in between 10 and 70 years (Figure 16). No downward trend has been foreseen by this analysis.

34

Figure 16. Nitrate concentration trend of the main water abstraction points of the Hesbaye aquifer (Data source : HGULg).

The use of modelling tools

In Aquaterra, HGULg has developed a distributed large scale groundwater flow and solute transport model for the Geer basin to perform nitrate concentration trend prediction. This model can be used, for example to investigate the impact of nitrates on groundwater.

Box 3. Development of a large scale groundwater flow and solute transport model (Source: HGUlg)

The large scale approach

Large scale groundwater solute transport models have to face different problems related to (1) the difficulty in quantifying/or scaling transport processes and (2) the numerical solution of the equation classically used for modelling transport processes. The challenge consists thus in finding a good compromise between the physical description of the phenomena governing groundwater flow and solute transport and the numerical approach of the model. HGULg has developed a general approach for modelling large scale contaminant transport in groundwater at the basin scale. Besides the classical flow and advection-dispersion equations, different mathematical and numerical solutions of the groundwater flow and transport equations have been implemented in the SUFT3D code (Saturated Unsaturated Flow and Transport in 3D). These different equations can be chosen depending on the extent of knowledge of the hydrogeological conditions. A complete description of the methodology is proposed in Deliverable R3.18.

The Groundwater model developed for the Geer basin

The groundwater flow and solute transport model developed in the framework of the Aquaterra project is a 3D multiplayer distributed model. The definition of appropriate conditions at the boundaries of the model allows adequate simulation of recharge, exchanges with rivers and the water leaving the aquifer through galleries and pumping wells. Horizontally, the limits of the modelled area have been defined as corresponding to the Geer hydrological basin. Vertically, the different layers define the model.

Input of nitrate leaching in the groundwater model

The unsaturated zone of the aquifer plays a key role in the dynamics of nitrate transfers. Many datasets coming from the Geer basin exhibit clear variations in nitrate concentration. As discussed by Brouyère et al. , (2004), such periodic variations are explained by groundwater table fluctuations in the variably saturated dual-porosity chalk. Nitrate spread over the land surface progressively infiltrates across the unsaturated zone, then migrates slowly through the unsaturated chalk matrix. Under low groundwater level conditions, the nitrate contamination front is disconnected from the aquifer and nitrate concentrations in the aquifer tend to diminish due to dispersion and mixing processes. When groundwater levels rise, the contamination front is quickly reached and nitrate concentrations are likely to increase rapidly in the saturated zone. It is therefore important to represent adequately the unsaturated zone. The groundwater recharge and the nitrate fluxes transmitted by UHAGx are computed at the mean groundwater level. Because the aquifer is unconfined, these fluxes computed at the top of the chalk layers would be more adequate to represent the time variations in groundwater levels and in nitrate concentrations in the unsaturated zone.

35

3.3.3. Relationships between groundwater degradation and adaptation of affected economic activities (from State to Impacts)

For each potentially affected economic sector, a threshold value generally characterises the state of the resources when damage could occur to the sector. According to Görlach et al. (2003), this threshold value may differ according to whether groundwater is used as drinking water, as an input in the food and beverage industry, as drinking water for livestock, for irrigation, for industrial processes or simply as cooling water. A damage function which relates pollution to economic impact will thus be discontinuous. Figure 17 is a simplified scheme of the relationships between the State, the threshold value and related economic damage.

Figure 17. Relationship between status indicator and damage

For each affected sector i, a damage function Di may be defined. For instance in scenario A (without policy) let d i (t) be the annual damage that occurs to the sector i when the threshold value is exceeded, T i the time when quality and/or quantity exceed the threshold value and CA T i the time when the quality and/or quality go under the threshold value (Figure 4): S A

i TSA 1 D i = .d i (t) A ∑ + t t=T i 1( a) C A a is the discount rate.

For each potentially affected sector, damage may thus be assessed as a function of nitrate concentration at the location of the abstraction point.

36

Box 4. Pumping wells, galleries and rivers (Source: HGUlg)

As the developed model is spatially distributed, the evolution of the concentration can be computed in every location in the basin. However, the model has to be first calibrated and validated. At the moment, only the groundwater flow model is calibrated in steady state. In the next months, the solute transport model will be calibrated for transient conditions.

The pumping wells, galleries and rivers are the natural or anthropogenic outlets of the aquifer. It is important to represent them adequately if we want to study the impact of the contamination for the different users or the surface water dependent ecosystems. In large scale models, it is impossible to take into account all the pumping wells or the river networks. In the model, only the galleries, the limit of the different layers and the boundaries of the hydrological basin were considered explicitly to build the 3D mesh. The fluxes pumped from wells have been taken into account by sink terms defined in the elements in which the well screens are located. Interactions between the rivers and the aquifer are modelled using face-based Cauchy boundary conditions, the exchange fluxes being a function of the difference of water level between the river and the aquifer.

Drinking water sector

Which adaptation in the case of contamination?

As shown in the Figure 16 , nearly 80% of wells will have exceeded the drinking water limit within 40 years if no additional preventive measures are taken. Even if it is still possible to use water from the northern gallery to allow the limit to be observed, this would not be possible in the event of generalized contamination. The contamination of a well requires quick decision-making if the manager wishes to continue the production and the distribution of drinking water. For this purpose several alternatives are possible for the managers. In the short term, however, these can be only curative actions.

In order to better understand which strategies are likely to be selected in the event of groundwater contamination, an expert of the CILE was consulted. The type of solutions to be considered is a question that has not yet been resolved in the CILE , but the expert suggested three main types of strategies, depending on the duration of the contamination and the mode of production (galleries or wells): (i) the dilution of the contaminated water with surface waters of better quality; (ii) treatment by denitrification; (iii) treatment by reverse osmosis.

The first two options are recommended in the event of short-term contamination (less than 5 years). The dilution of groundwater with surface water of better quality is under study in the CILE . The surface water must be bought to another producer that abstracts from surface water. Its production cost is higher than Hesbaye groundwater (production itself, treatment and transport). Considering a dilution of 15%, the additional cost would be approximately 0.48 €/m 3. Treatment by denitrification could be used for the small intake points (approximately 5% of the production of the galleries). The economic synthesis carried out by the Adour Garonne Water Agency in France (AEAG, 2003) may be used initially to consider the costs related to the establishment of a denitrification station.

The third option would be considered in the event of pollution of longer term pollution (> 5 years) and consists of carrying out a generalized water treatment, possibly coupled with a softening process (the hardness of Hesbaye water is approximately 42 French degrees). The operating cost of water treatment by reverse osmosis is currently estimated at approximately 0,13 €/m 3 produced. 13

Within the framework of a business as usual scenario, we estimate here that once the drinking water limit has been exceeded, the nitrate concentration in groundwater will remain higher than 50 mg/l for an indefinite period. In this case, the third option would be

13 Investment cost may be estimated with data from the Fédération des collectivités de l’eau website (http://www.fcehn.fr/Upload/medias/traitementdesnitrates.pdf)

37

implemented by the CILE and the second option would be implemented by the other drinking water companies.

Main factors influencing the economic damage

In a general way, the value of the impacts of nitrate contamination on the drinking water D sector DW can be expressed in the following way:  T  = = 0 0 λ φ DDW ∑ Di ∑ ∑ fi ([ NO ]3 i ,Tc i ,Vi , ,C( i ), a,T ) = i i t Tc i 

Di is the value of the impact of the contamination for a drinking water unit i (DWU i). 0 [NO ]3 i is the average nitrate concentration of DWU i at the year t 0. Tc i is the year at which the average nitrate concentration is likely to exceed the drinking water limit. 0 Vi is the volume abstracted by DWU i at the year t 0. λ is the annual growth rate of the volume abstracted by DWU i (%), based on the forecast of the demographic growth rate. φ C( i ) φ is the cost of implementation of a palliative solution i to the pollution of DWU i, including the investment and recurring costs. a is the discount rate. T is the year at which the evaluation stops.

Industrial sector

Trend extrapolation carried out by HGULg and applied to the industrial intake points shows that the standard of 50 mg/l could be exceeded within approximately 80 years. We have not continued at the present time with the assessment of industrial sensitivity to groundwater nitrate contamination. Contacts have been established by HGUlg with the biggest agro-food enterprise that could be affected by nitrate pollution.

Households

Which adaptations in the case of contamination?

Households may be affected by the progressive degradation of the resource by increasing the quantity of bottled water in their daily water consumption for example, or by using individual purification systems. Although the nitrate concentration of distributed water would not exceed the limit of 50 mg/l, the quality degradation may encourage households to consume bottled water, which results in additional costs. Nevertheless, it is difficult to know precisely what the proportion of bottled water consumption related to nitrate pollution of the water resource would be (commonly the first evoked reason is the bad taste of the tap water 14 ).

14 Source: http://www.aquawal.be/xml/fiche-IDC-177-IDD-334-.html

38

Moreover the degradation of the water resource may also lead to additional costs in the coming years for drinking water producers and thus consequently for users (impact on the water price).

Main factors influencing the economic damage

An assessment of the additional costs related to the contamination of groundwater resources was carried out on the Alsace aquifer (Rinaudo, 2004). As an illustration, we will use the main assumptions of this study, adapted by using data relating to the Walloon Region when they are available. The current function of damage can be expressed as follows:

D 0 = f (Pop 0 ,α 0 , β 0 , p , p ) H b d

α 0 is the mean average bottled water consumption per inhabitant (l/inh./year)

β 0 is the part of the bottled water consumption due to the fear of tap water contamination by nitrates (%)

pb is the price of bottled water (€/l)

pd is the price of tap water (€/l)

In a scenario of progressive groundwater quality degradation, we may reasonably think that the bottled water yearly consumption will increase.

D (t) = f (D 0 ,t) = f (Pop ,α, β , p , p [, NO ],3 t) H H b d

If we refer to the evolution of bottled water consumption in the Walloon region 15 since 1980, and if it is considered that consumption will continue to grow at the same rate as during the 1980 – 2001 period, the annual additional cost related to the bottled water consumption would grow of 5.4% per year (a doubling in 13 years). Nevertheless, these results should be treated with caution since they are based on a significant number of assumptions. In order to improve and provide quality control for this analysis a survey could be conducted with the local population.

We should also note that the increased bottled water consumption generates an environmental cost which is not negligible. The production and transport of bottles requires much more energy than tap water production. Plastic bottles may also be a source of pollution for environment.

Moreover a decrease in tap water consumption may also affect water price. If purchase of tap water decrease, the part of investment cost of the drinking water producer per cubic metre (investment cost = constant, water volumes = decreasing) will increase.

3.4. CONCLUSION

A simplified integrated conceptual model has been built in this chapter to analyse one of the main groundwater management issues at stake in the Geer basin. It shows how the main components of the system may evolve and interact between them in the coming years.

15 Source: http://www.aquawal.be/xml/fiche-IDC-179-IDD-333-.html

39

Several analysis levels were initially considered for the development and the application of the conceptual model (Figure 18). These levels describe (with an increasing precision) how relationships between Drivers (external and internal), Pressures, State and Impacts may be understood in a conceptual model. The first level is mainly based on the use of statistical trend analysis tools: it is considered as the simplest level as it can not take into account the effects of the change in one component of the system to another. The second level is more complex as it requires the use of economic and hydrogeological modelling tools: at this level an integrated model (integrating TREND, BASIN and INTEGRATOR) could be expected. The third level integrates also climate change data that could be provided by HYDRO H1. Currently knowledge and data are sufficient to apply the first level of the conceptual model, based on trend extrapolation.

Figure 18. Three levels of precision for the conceptual model of the Geer case study

Further investigations will be made in the coming months to simulate potential economic impacts due to change in agricultural practices and/ or change in groundwater nitrate concentration (from drivers to pressures to state to impacts) taking into account TREND, BASIN and HYDRO new developments. The aim will be to improve the level of analysis by the coupling of the evolution of each component of the system (from the 1 st level to the 3 rd level in Figure 18).

This conceptual model could be used in Integrator 3 work package to illustrate the assessment of (i) economic damage that could occur due to nitrate pollution of groundwater in the coming decades (no-action scenario) and (ii) the effects (in terms of effectiveness and/ or benefits) of the implementation of preventative measures (in the framework of Water

40

Protection Areas designation for instance) 16 . This application could be an illustration of a decision support tool analysing diffuse agricultural pollution of groundwater at a small basin scale. Further investigations would be required to develop such a decision support tool at a larger scale.

REFERENCES

AEAG (2003). Surcoûts supportés par les usagers domestiques du fait des pollutions par les nitrates et les pesticides - Synthèse des données disponibles version 3 - novembre 2003.

AERM (2004). Eléments de diagnostic de la partie française du district Meuse et Sambre. DCE. Etat des lieux des districts Rhin et Meuse - partie française.

Ansink, E., Ruijs, A. & van Ierland, E. (2005). Report with characterisation of impact of global change on economic activities (having an impact on - or depending on water-soil resources) in the four river basins. Deliverable 2.2 from Aquaterra project. Environmental Economics and Natural Resources Group, Wageningen University.

Batlle Aguilar, J., Orban, P. & Brouyere, S. (2005). Point by point statistical trend analysis and extrapolated time trends at test sites in the Meuse BE (ULg). extract from the TREND 2.4 deliverable "Report on extrapolated time trends at test sites". Aquaterra project.

Bouzit, M., C. Hérivaux, et al. (2005). A case study report on the Meuse by BRGM in relation with EUPOL and BASIN. Montpellier, BRGM: 64.

Brouyere, S., A. Dassargues, et al. (2004). “Migration of contaminants through the unsaturated zone overlying the Hesbaye chalky aquifer in Belgium: a field investigation.” Journal of Contaminant Hydrology 72(1-4): 135-164.

Dautrebande, S. & Sohier, C. (2004). Modélisation hydrologique des sols et des pratiques agricoles en Région wallone (Sous-bassins de la Meuse et de l'Escaut). Rapport final du Programme Intégré de Recherche Environnement-Eau (PIRENE) Mars 2001-Octobre 2004. Faculté Universitaire des Sciences Agronomiques de Gembloux (FUSAGx) Génie Rural & Environnemental - Unité d'Hydrologie & Hydraulique agricole (HA-FUSAGx).

Defra. (2004). Strategic review of diffuse water pollution from agriculture. Initial appraisal of policy instruments to control water pollution from agriculture. Department for Environment, Food and Rural Affairs.

DGRNE (2005). Etats des nappes d'eau souterraine de la Wallonie, Ministère de la Région Wallone - Direction Générale des Ressources Naturelles et de l'Environnement.

Görlach, B. & Interwies, E. (2003). Economic Assessment of Groundwater Protection:A Survey of the Literature. Ecologic. Final report ENV.A.1/2002/0019.

Hallet, V. (1998). Etude de la contamination de la nappe aquifère de Hesbaye par les nitrates: hydrogéologie, hydrochimie et modélisation mathématique des processus d'écoulement et de transport en milieu saturé. Thèse. In Laboratoires de Géologie de l'Ingénieur, d'Hydrogéologie et de prospection géophysique, Université de Liège - Faculté des sciences.

Halm, D. and P. Grathwohl (2005). Integrated Soil and Water Protection: Risks from Diffuse Pollution. Research needs defined by SOWA. Tübingen (Germany), University of Tübingen, Center for Applied Geoscience: 65.

16 See the methodological guidelines developed in § 2.3

41

IMC (2005a). International River District Meuse. Characteristics, Review of the Environmental Impact of Human Activity, Economic Analysis of Water Use, Roof report. Liège, International Meuse Commission. March 2005.

IMC (2005b). The International River District Meuse: a status assessment. Liège, International Meuse Commission. November 2005.

Loubier, S. (2004). Modélisation du comportement des agriculteurs: revue de littérature. Rapport final, BRGM: 22p.

NL-Water (2004). Karakterisering Nederlands Maasstroomgebied. Rapportage volgens artikel 5 van de Kaderrichtlijn Water (2000/60/EG). Definitive rapport, 21 December 2004, Government of the Netherlands.

Orban, P., Batlle Aguilar, J., Goderniaux, P., Dassargues, A. & Brouyère, S. (2006). Description of hydrogeological conditions in the Geer subcatchment and synthesis of available data for groundwater modeling. Deliverable BASIN R3.16 of the Aquaterra project. University of Liège.

RBO-Maas (2004). Karakterisering Nederlands Maasstroomgebied - Rapportage volgens artikel 5 van de Kaderrichtlijn Water (2000/60/EG) - Definitief rapport.

Rinaudo, J., Arnal, C., Blanchin, R., Elsass, P., Meilhac, A. & Loubier, S. (2004). Assessing the cost of groundwater pollution: the case of diffuse agricultural pollution in the upper Rhine valley aquifer.

Rivington, M., Matthews, K. B., Bellocchi, G., Buchan, K., Stockle, C. O. & Donatelli, M. (2005). An integrated assessment approach to conduct analyses of climate change impacts on whole- farm systems. Environmental Modelling & Software, In Press, Corrected Proof.

RW (2006). Les subventions agri-environnementales instaurées par l'AGw du 28 octobre 2004, Vade- mecum, édition du 27 janvier 2006, Ministère de la Région Wallonne. Direction générale de l'agriculture. Division des aides à l'agriculture. Direction du secteur végétal.

42

4. The Kempen area (Meuse, Flanders & the Netherlands): soil contamination by heavy metals

For further information, please contact Madjid Bouzit (BRGM) – [email protected]

This chapter will provide an overview of the preliminary investigation and discussions on the implementation of the DPSIR framework for soil-sediment-water system contamination by heavy metals in the Kempen area, located within the Meuse River Basin. The heavy metal contamination in the Kempen area is the second case study selected for analysis of the socio-economic impacts of management scenarios and environmental future change in the system.

4.1. INTRODUCTION – CONTEXT AND AIM OF THE STUDY

4.1.1. General context – Heavy metal contamination

While diffuse contamination is difficult to localise, local contamination (or point source) problems occur in specific sites. A contaminated site is defined as one with a confirmed presence of dangerous substances (e.g. heavy metals) caused by man at such a level that they may pose a risk to a “receptor” and remediation is needed.

Heavy metal contamination is one of the main threats affecting the soil-sediment-water system in European river basins. Typical heavy Metal contaminants include cadmium (Cd), lead (Pb), chromium (Cr), copper (Cu), zinc (Zn), mercury (Hg) and arsenic (As). Contamination comes mostly from non-ferrous metal industries, power plants and the iron, steel and chemical industries. Other source include sewage sludge spread for agricultural purposes, discharge from waste incineration plants and the use of contaminated manures in agriculture.

Point source contamination affects both the soil itself (primarily at a local level) and other media (e.g. water and sediment). Soil contamination restricts the buffering and substance conversion capacities of soils. Leaching processes can contaminate both surface and groundwater, and can potentially have significant effects on both human and ecological health. The different impacts of soil contamination include: • Risk to human health for people living on and in the surroundings of a contaminated site (through different exposure paths, such as the consumption of food grown in contaminated areas, or drinking water extracted from contaminated aquifers); • Contamination of surface water, mainly through run-off of contaminated sediments and contamination of groundwater; • Risk of ecotoxicicological conditions for the flora and fauna living in the soil on the site and around the contaminated area, resulting in loss of biodiversity and biological activities; • Loss of soil fertility due to disrupted nutrient cycles, • Restrictions on land use, hindering future redevelopment and reducing the area of productive and valuable soil available for other activities (agricultural and forestry production, recreation etc.); • Depreciation of land and real estate value.

43

Remediation of heavy metals contamination has strong links with EU environmental policies such as soil and air policies, industrial pollution control, as well as the water and groundwater directives.

4.1.2. Kempen case study: General description

This section gives a general description of the Kempen area. It is based on the information and data that are currently available. Despite the significant amount of data and information on site contamination by heavy metals, the following section is restricted to the Cadmium (Cd) and Zinc (Zn) pollutants.

Location

The Kempen region is located at the border of Belgium and the Netherlands. It includes the provinces of North Brabant, Limburg-NL (in the Netherlands), Limburg-Fl and Antwerpen (in the Flemish region). The Kempen region is within the Dommel river catchment (Figure 19). Hydrologically, the Dommel water system is one of the important tributaries of the Meuse. The catchment area covers about 1,700 km 2. It is characterized by a large diversity of habitats, has high potential ecological values and serves as an important research investigation area in the AquaTerra work packages for the Meuse River Basin (refer to the AquaTerra meeting Dommel/ Meuse - January 31 st , 2006).

Figure 19. Location of the Kempen area and the Dommel catchment as part of the Meuse River Basin

44

For the purpose of the DPSIR analysis, the study area is limited to the area with high concentrations of metals in the soil, referred to here as the “Kempen area”. The total surface area represents about 700 km 2. The environmental boundaries are based on the delimitation of BeNeKempen project area and are slightly different than those of the AquaTerra project. 17

Heavy metal contamination issue

The Kempen area is one of the most important non-ferrous metal production sites in Europe. According to the OVAM 18 , nine historical or operational industrial plants are localised in the area (Figure 20): • Three operating zinc-ore plants are located within 10 km of each other (Overpelt, Balen and Budel); • Two other former plants (Lommel and Rotem) in Belgium were shut down in 1970’s; • Three lead plants (Hoboken, Beerse and Olen) are located in the eastern part of the Kempen area. The Hoboken and Olen plants are still in operation. • An arsenic production plant (Reppel) was closed in the same period.

The industrial plants in operation are owned by Umicore (Belgium - the former Union Minière, for the sites of Balen, Olen, Overpelt and Hoboken) and the Budelco Zink Company (The Netherlands) for the site in Budel.

Considering only the Zn-plants, around 600,000 tonnes of zinc products are manufactured each year at the Overpelt, Balen, and Budel sites, using both from zinc ores and recycled zinc-containing materials as raw material.

Figure 20. Localisation of the industrial activities in the Kempen Area (source: OVAM)

17 AT activities in the area differ in terms of spatial scale of analysis (part of Dommel catchement), component of the system studied (soil, sediment or groundwater) and pollutants investigated (Pb, Zn, Cd, Nitrate, etc.). 18 OVAM (Openbare afvalstoffenmaatschappij voor het Vlaamse Gewest) is a Public Waste Agency of Flanders (http://www.ovam.be/jahia/do/pid/1287).

45

Heavy metal contamination has its origin in past industrial activities, started around 1900. At each site a large variety of different metal contaminants are represented (zinc, cadmium, lead and to lesser extent arsenic and copper). Due to the long history of industrial activities, the emissions of oxide metals have been dispersed over the surrounding area impacting upon the environmental system.

Besides the smelting of heavy metals, different pollutants such as sulphuric acid and sulphur dioxide were also produced. In the 1960s, emission controls were introduced focused mainly on sulphur dioxide due to concerns related to forest decline. Persistent heavy metals were not considered a priority at that time.

Since the seventies, clean industrial production processes have been introduced, but heavy metals have already polluted all components of the soil-sediment-water system and the process will continue for decades unless specific actions are taken.

The issue of heavy metal contamination was addressed separately in the Flemish and the Dutch parts of the Kempen region. In 2002, the Belgium and Dutch government signed a memory in which they agreed to cooperate in finding a solution for heavy metal contamination in the Kempen area. High attention is being given to the costs and environmental efficiency with respect the cleaning of Cadmium and Zinc contamination.

4.1.3. Overall objective of the case study

The main objectives of this chapter was to develop a comprehensive conceptual framework (i.e. DPSIR) applied to contamination that would help in establishing links between AquaTerra activities in developing physical and economical models and formulation of scenarios and management measures. For this purpose and for the purpose of the economic analysis to be carried out in Integrator WP, contacts with other projects were established including:

BeNeKempen project

BeNeKempen (for Belgium - the Netherlands Kempen) is an Interreg III project started in 2004. The project aims to combine existing data and actions to make a complete inventory of contamination issues, to implement cross-border measures in managing soil and water contamination by heavy metals. By 2008, remediation measures for the entire region are expected to be defined and to become available for implementation.

AbdK project

In the Netherlands, the project agency 'Actief Bodembeheer de Kempen' (AbdK or Campine Active Soil Management) has since 1998 been involved in the development and the implementation of a socially responsible management program of soils polluted with heavy metals in and around the Dutch Kempen area.

4.2. APPLYING THE DPSIR FRAMEWORK

The DPSIR conceptual model has been used to represent the issue of heavy metal contamination in the Kempen area. This case study focuses specifically on cadmium and zinc, which are the most widespread pollution threat in the area. The objective was to specify the different parameters (4.2) and relationships (4.3) of the DPSIR components that need to be investigated for the economic assessment of potential responses (4.4).

46

4.2.1. Drivers Past industrial activities are the main driver that affects the type and extent of zinc and cadmium contamination in the Kempen area. Usually, emission (tones/year) or atmospheric deposition (g/ha/year) is used as an indicator to assess the driver. Historical atmospheric deposition figures were estimated for the period 1880-1975 by van der Grift et al. (2005): • 15 - 642 g/ha/year for cadmium; • 730 – 25,000 g/ha/year for zinc. The above figures represent average values estimated for nineteen locations in the Netherlands part of the study area. These values vary strongly with the distance from the Zn- plants.

In addition to the past smelting activities, the spread of pollutants was aggravated by the following activities: • Agricultural (and to a lesser extent gardening) activities using of contaminated compost to improve the organic content of agricultural soil. In the past, farm activities in the area changed from dairy farming to intensive livestock farming (particularly due to the introduction of the maize crop in Brabant). The manure from this type of farming is spread on a relative small area of land, leading to a large load of pollutants including metals (i.e. cadmium and zinc). The average agricultural load is 1.48 g/ha/year for Cd and 605 g/ha/year for Zn ( van der Grift et al., 2005). • Irrigation with contaminated surface water can also spread contaminants to agricultural land. However, the agricultural load of heavy metals is small compared to historic deposition in the vicinity of the smelters. • The use of industrial residues (ashes, slag and muffles) for the hardening of public roads, bicycle paths, industrial lands and soil improvement around farms. Currently, it is known that in the Flemish provinces of Antwerp and Limburg about 490 km of roadways have been constructed with materials containing residues of zinc and/or lead distributed over the former industrial lands. In the Netherlands, about 833 km of roadways have been registered. • Within the water cycle, the direct discharge of waste water from industrial operations into surface water has led to the contamination of several layers of groundwater. Besides these anthropogenic activities, natural factors such as flooding and climate change can also be considered as drivers for heavy metal contamination.

4.2.2. Pressures

Exhaust fumes from industrial smelters have emitted oxides of heavy metals for about one century: these have reached the soil either by dry atmospheric deposition or have precipitated out with rainfall. Soil acts as the key zone for the storage of metals and has become a source of diffuse pollution releasing contaminants to adjacent compartments of the system such as sediments; surface water and groundwater. Due to filtration, the groundwater is also heavily contaminated. It was estimated that at least 30,000 kg zinc and 1,000 kg cadmium has entered the Dommel water system through run-off and leaching originating from the polluted soils and groundwater ( Owens and Edlman, 2003 ). Cadmium adheres to suspended particles and sediments. Annually 980 ha of the Dommel floodplain are inundated, thus cadmium contaminated sediment is deposited. Cadmium leaches from floodplain soils and is transported to and through the groundwater.

47

The interaction between different compartments of the system has finally lead to a complex and heterogeneous heavy metal pollution case, covering an extended area and having been spread out to different environmental components including soils, sediments, surface water and groundwater. Figure 21 gives a schematic representation of this interaction.

Figure 21. The pressure of industrial pollution on soil-sediment-water system (source: OVAM, 2006)

4.2.3. State

The extent of pollutants, especially cadmium (Cd) and zinc (Zn) on the soil-sediment-water system has been examined since the beginning of the eighties and most of the spread has been mapped. The indicative concentration values given here are based on available data.

Soil

In areas adjacent to industrial plants high contaminant concentrations (i.e. 10 to 100 times higher than average) are found in surface top soils (0-30 cm). On average Cd concentrations in contaminated soils range between 1.8 and 8.7 mg/kg in the Netherlands and between 10 and 67 mg/kg in Flanders. It was estimated that about 500 km² (in both the Netherlands and Flanders) have a concentration Cd > 1 mg/kg of top soil (Figure 22).

48

Figure 22. Cd concentration in the Kempen Area (source: OVAM, 2006)

River sediments

Cadmium concentrations from 3 to 30 times higher than background levels are reported in surface layers of sediments as a result of soil and water contamination. Concentrations in river sediments show increased concentration in Cadmium in most Dommel upper tributaries. In polluted rivers, levels range from approximately 30 to 400 mg/kg in sediment. Extremely polluted river sediments can reach 800 mg/kg and even higher, concentrations increasing upstream in the direction of the source of pollution. In total it has been estimated that about 61 km 2 of river sediments of the Dommel system contain more than 5 mg/kg cadmium.

Water

In the study area, the groundwater layers are sandy clay, limestone and gravel and are vulnerable for leaching due to the geological condition (see Deliverable Trend 2.1). Groundwater is known to be affected by pollution near the industrial plants. Concentrations in cadmium from 1 µg/l to 300 µg/l and in zinc from 10 µg/l to 50,000 µg/l have been observed in groundwater of Dommel catchments. In the shallow groundwater layers, cadmium concentrations were found to vary from detection limit (0.1 µg/l) to 25 µg/l, with a mean value of 3 µg/l. 19

In surface water, cadmium concentrations vary between 1 and 80 µg/l and zinc concentrations between 30 and 2,100 µg/l.

4.2.4. Impacts of contamination

The state of the soil-sediment-water system discussed above led to adverse impacts on the socio-economic system in an extended area around Kempen site. There are a number of stakeholders which may be affected by contamination. These include householders, farmers, commercial and industrial businesses, state government agencies, public utilities and local municipalities. Metal contamination may also have adverse impacts on the environmental

19 Source: European Chemicals Bureau (2000), IUCLID dataset – substance ID 7440-43-9 (Cadmium).

49

system. In the following sections, potential impacts for humans, agriculture and ecosystems are qualitatively described.

Impacts on public health

Cadmium is toxic at low concentrations. Poisoning symptoms occur at 10 mg/l of blood (malfunctioning of the kidneys, increasing bone porosity, hypertension) and can become fatal at 325 mg/l. According to the Word Health Organisation, the maximum permitted load for cadmium is 400-500 µg/person/week.

Presently, there is a consensus that exposure to Cd at contaminated sites can result in a potential increase of human health risk (30% more than for people living in an area which is not contaminated). 20

Exposure risk is mainly due to the following pathways: indoor dust inhalation / ingestion; soil ingestion; and consumption of contaminated vegetables. Recent investigations in the Kempen area indicate that exposure through soil is as high as exposure due to consumption of vegetables. Metals readily accumulate in crops especially in acidic soils with low binding capacity. Albering et a l. (1999) have evaluated heavy metal exposure risks for inhabitants in the Limburg province through the analysis of the extent of heavy metal uptake by vegetables and crops harvested in the area during winter of 1993. The Cd concentration level in the main vegetables are summarised in the following table (Figure 23). The result shows that the maximum Cd concentrations can easily exceed the standard limits of the Dutch commodity acts for certain crops.

Heavy metal Cd Zn Vegetables and crops Range Standard (1) Range Standard Lettuce 0.03–0.21 - 5.4-9.1 - Potatoes 0.02–0.12 0.1 1.8-6.1 - Beans < 0.03 - 4.3-6.3 - Wheat 0.01-0.26 0.15 19-41 - Silage maize 0.14-6.8 1 - Ryegrass 0.03-0.84 1 - -

Figure 23. Concentration of Cd and Zn in some vegetables and crops in Limburg (in mg/kg)

Impacts on agriculture

Soil contamination by heavy metals is often discussed in relation with the food-chain safely issue as outlined above. This can directly impact upon the agricultural production activities. For instance, production losses when metal concentrations exceed the legal standards for concentration in vegetables and animals.

Agriculture and livestock production is an important activity in the provinces of the Kempen area. Besides production figures in the area, other economic impacts on agriculture may include: • Reduction in the economic value of agricultural land due to soil contamination. • Reduction of farm productivity and loss of contaminated production. • Restriction on the exports of food and meat produced in the area.

20 Copius et al. (1989). The intake of cadmium in the Kempen, an area in the south of the Netherlands. Ecotoxicology and Environmental Safely, vol. 18, issue 1, pp 93-108.

50

Impacts on urban areas

The economic impacts of contamination within urban areas include: • Loss in real estate transactions (the market value of property will decrease). • Cost incurred by soil cleaning in urban parcels (individual properties). In the Flemish part of the area, soil clean up around the industrial site is under investigation. • Cost of removal zinc ashes from roads.

Impacts on ecosystems

Soil contamination may disturb the ecosystems and change biodiversity (soil habitats and species). In the Kempen area, several studies have outlined ecotoxicity of Cd and Zn accumulation in natural organisms. For instance, Gorree et al . (1995) have estimated and modelled the risk of Cd contamination for terrestrial vertebrates through the food chain. The results indicated high Cd concentrations in the area posed a risk for the species considered in the study area.

Additional impacts • Potential restrictions on groundwater use for drinking purposes and increased production costs of the water supply (cost of water treatment). Cadmium belongs to the list of the 11 priority hazardous substances established by the Water Framework Directive. 21 • Decrease of public appreciation of the natural reserve in the area, which may impact recreational activities and the tourism sector. • Monitoring costs incurred by public authorities and agencies for monitoring environmental, food and health parameters.

4.2.5. Responses

Adverse impacts may be mitigated by specific responses or measures. Different levels of responses can be envisaged. First, responses could be: (i) technical measures, affecting pressures or state (such as soil remediation and water treatment); (ii) mitigation measures aimed at reducing pressures (e.g. reduce metal uptake by crops); (ii) curative measures aimed at reducing impacts (e.g. public health campaign) (vi) institutional (policy) measures directed towards driving forces (e.g. legislation, standards on emission control/reduction, new industrial technology). Secondly, these responses could be dedicated to either one media of system or to the whole soil-sediment-water system. Thirdly, the responses could be addressed locally (e.g. on-site remediation) or at a more global level such as policy measures.

Following the DPSIR scheme, some examples of existing or possible responses in the study area are listed below. This list is not exhaustive and the future actions to be undertaken are still under study jointly in Flanders and the Netherlands.

For the driving forces component measures have been taken to reduce industrial emissions such as: • Installation of filters and control / reduction of heavy metal emissions in the zinc smelters that are still in operation;

21 The priority hazardous substances will be subject to cessation or phasing of discharges, emissions and losses within an appropriate timetable that shall not exceed 20 years.

51

• Industrial pollutant discharges into surface water have been restricted since the 1990s. A large portion of treated water is re-used as process water by the industry; • Use of enclosed rail wagons for transporting zinc-ore to reduce the spreading of ore;

• Removal of slag from roads to reduce diffuse contamination to groundwater. The inventory of the roads contaminated with metal slag has been completed in Flanders and the Netherlands.

For the pressures and state components, possible actions could aim at reducing the heavy metal concentrations in the soil-sediment-water system:

• Contaminated sediments will be dredged and removed to a controlled landfill. A sediment trap has been installed in the Netherlands (near Eindhoven) in order to keep the Dommel river free of contaminated sand.

• Groundwater contamination at the industrial sites has to be controlled by pump and treat technology or alternative solutions (i.e. permeable reactive barriers, in situ treatment techniques, …). In some cases, the effluent from this treatment can be used as industrial process water.

• Limitation of the use of contaminated groundwater resources can be implemented (it will be forbidden for drinking water purpose);

The best available technologies for soil and groundwater remediation and/or industrial emission control could be used. A review of these technologies is detailed in section 5.

For the impact component, precautionary measures are focused on human health. For instance, in Flanders, the following measures have been taken:

• Cultivation of food crops has been forbidden, or limited to certain crops (with restricted metal uptake characteristics). For instance in 2004-2005, the federal agency for the safety of the food chain (FAVV) prevented the distribution of carrots and ‘schorseneren’ produced in the Kemen area. The Flemish government was in charge of financial compensation to farmers.

• The export of old cattle has been forbidden and kidneys of cattle from the area are now removed – to be in agreement with EU regulation and to avoid the export of contaminated food.

• Highly contaminated areas are being cultivated with special Zn-resistant grasses and soil additives; the plant cover should prevent the dispersion of metal-laden dust.

4.3. IDENTIFYING THE RELATIONSHIPS OF THE DPSIR

The next step in the conceptual model development was to identify the relationships between the components of the DPSIR framework, which in the original framework was simply a cause-effect matrix of indicators. This section aims to outline the needs of quantitative models, relating each component of the framework to the integrated assessment of heavy metal contamination in the area.

52

4.3.1. Relationship D – P: pollution source assessment

In the environmental pollution literature, this type of relationship is often referred to as the source-pathway-receptor approach (see Welcome 22 project for example), which relates driving forces to their pressures on the environment. For the case studied, the following general formula can be used:

Contaminant load = Atmospheric deposition * Intensity * Penetration factor

Where contaminant load represents the actual input of heavy metal into the soil component in the area, Intensity represents the annual atmospheric deposition per unit of surface area (Kg/ha) and the penetration factor incorporates a possible retardation factor of contamination.

4.3.2. Relationship P – S: mass flux model

Empirical or analytical mass flux models are generally used for describing the relationship between pressures and the resulting state of the soil-sediment-water system. Such models are usually established on the basis of physical, chemical and ecological processes between the time of emission and the time when this emission reaches the soil-sediment-water system.

In AquaTerra project, the P-S relationship is investigated under the Flux 2 work package. A diffuse transport model is being developed to analyse the leaching of heavy metals from the topsoil to subsurface water and groundwater ( Valstar et al., 2005). Based on the preliminary modelling of van der Grift et al . (2004), three geohydrological systems were distinguished (i) the topsoil and unsaturated zone, (ii) the saturated zone and (iii) the flux from the groundwater to the surface water system. Leaching of cadmium and zinc from topsoil to groundwater in the Kempen area is considered spatially highly variable and depending on parameters such as: input load of the metals by atmospheric deposition, land-use, groundwater depth, soil type and precipitation.

4.3.3. Relationship S – I

Risk analysis models may be used to assess the links between the state of the system and its socio-economic and ecological impacts (i.e. agriculture, public health, and ecosystems). The actual impacts of contamination are not quantified for the studied area but have been described qualitatively in the previous section of this chapter.

Global S-I relationships have not yet been studied in the AquaTerra project. However, different studies have reviewed the impacts of heavy metals contamination in terms of risk- based analysis (see Bardos et al., 2000 and the CLARINET project 23 ) or in terms of monetary assessment ( Darmendrail et al, 2004 and Görlach et al., 2004 ).

4.3.4. Relationship R – [DPS]: scenario analysis

The R – [DPS] relationship investigates different scenarios of change. First, trends of driving forces, pressures and state have to be modelled and calibrated using statistical approaches or expert-judgement methods. Secondly, these models have to be applied to assess the future impacts of alternative responses and to develop future scenarios.

22 http//www.welcome.org. 23 Clarinet (Contaminated Land Rehabilitation Network for Environmental Technologies in Europe) final reports are available at http://www.clarinet.at/.

53

For the area studied, the trend of Cd and Zn concentration in groundwater (here taken as an indicator of the State of the study area) was analysed by Van der Grift (2004) for three sub- catchments of the Dutch part of the Kempen area (Beekloop-Keersop, Aa and Tungelroijsche Beek). Figure 24 gives the trend of cadmium load by subsurface outflow of groundwater to surface water in the Beekloop-Keersop and Tungelroijsche Beek sub-catchments. The modelled trend of concentration shows an increase for the next decades, reaching an average value of 5.5 µg/l in 2050.

Figure 24. Trend of Cd concentration in the surface water in two sub-catchements of the Kempen area (source: van der Grift 2004)

Within AquaTerra project, further trend modelling is being undertaken within the Trend 2 work package. The overall objective is to quantify and extrapolate the trends of heavy metal concentrations in groundwater bodies at the Dommel catchment scale. Scenarios of change in groundwater quality will be linked with change of land use, climate and contamination history.

It should be noted that this trend modelling is only being undertaken for groundwater quality. An equivalent approach may be needed for the soil and sediment compartments in the conceptualisation of the whole environmental system.

For the identification of scenarios, a number of assumptions can be made. In the implementation of the Biochem DSS in the Dommel catchment, the Basin 3 work package has introduced three sets of scenarios of change:

• Baseline scenario, without any new actions (no remediation measures);

• Worst case scenario, assuming higher contamination than the baseline scenario. This can be based on the overall trends of contamination in the vicinity of smelters;

• Best case scenario in which sustainable corrective measures will be undertaken. This situation would arise with trans-boundary cooperation between Flemish and Dutch stakeholders.

54

4.4. REMEDIATION MEASURES

In the frame of the DPSIR model, economic analysis aims to assess the appropriateness and the effectiveness of responses in reducing the impacts and the risks of heavy metal contamination on the system (Responses - Impacts relationship) for the different scenarios.

An economic analysis as applied to the Kempen area is presently being investigated within Integrator work package. In particular the cost-efficiency analysis of potential technical measures for soil and groundwater remediation will be developed. A preliminary step of the cost-efficiency analysis will be the identification of potential measures and their costs.

4.4.1. Potential technical measures

Beside the policy and precautionary measures focusing on human health, there are a range of technical measures for remediation of heavy metal contaminants from soil, surface water and groundwater. Most of them have been demonstrated in full-scale de-pollution projects and are presently commercially available. A comprehensive list of these technical remediation measures is reviewed in CLARINET (2002) and Evanko et a l. (1997). Usually remediation technologies are classified according to the type of treatment and include:

Isolation measures

Isolation or sealing measures attempt to prevent the migration of contaminants by containing them within a restricted area. These measures are used to prevent further contamination of surface water and groundwater for a site. Capping systems and subsurface barriers such as vertical barriers are examples of isolation measures.

Immobilization measures

Immobilization techniques are designed to reduce the mobility of contaminants by altering the physical or chemical characteristics of the pollutants to make them more stable in soils. A variety of technologies are available for the immobilization of metal contaminants, including (i) solidification/stabilisation treatment processes by injecting chemical agents into the contaminated soils and (ii) vitrification processes using thermal treatment to physically bind the contaminated soil or sediments.

Most of these processes can be performed ex-situ or in-situ. In situ remediation processes are preferred due to the lower labor and energy requirements. Ex-situ remediation requires excavation, transport and disposal of the treated material.

Treatment measures

The toxicity and the mobility of heavy metal contaminants can be altered by physico- chemical, chemical reactions and/or biological processes.

Three types of chemical reactions can be used: (i) oxidation (modification of the oxidation state of the metal through loss of electrons), (ii) reduction (by adding electrons) and (iii) neutralization reactions (pH adjustment of extremely acidic or basic contaminated soil or water).

Biological treatment processes are commonly used for the remediation of organic contaminants and are beginning to be applied for heavy metal remediation in contaminated sites. However, most of the applications to date in Europe have been implemented at a pilot scale ( CLARINET, 2002 ). Biological treatment exploits natural biological processes that allow certain plants and micro-organisms to aid in the remediation of metals. These processes occur through a variety of techniques, including:

55

• Bioaccumulation: involves the uptake of metals from contaminated media by living organisms or dead, inactive biomass. Active plants and micro-organisms accumulate metals as the result of normal metabolic processes;

• Phyto-remediation: some plants have the ability to remove ions selectively from the soil to regulate the uptake of metals. Most metal uptake occurs in the root system, usually via absorption, where many mechanisms are available to prevent metal toxicity due to high concentration of metals in the soil and water. Potentially useful phyto-remediation technologies for the remediation of metal-contaminated sites include phyto-extraction (the removal of metals from the soil by absorption into roots of the plant), phyto-stabilization (the use of high tolerance plants to limit the mobility and bioavailability of metals in soil) and rhizo-filtration (the removal of metals from contaminated groundwater via absorption, concentration and precipitation by plant roots).

• Bioleaching and biochemical processes: some micro-organisms dissolve metal contaminants either by direct action of the bacteria (bioleaching) or can producing chemical agents that can directly oxidise and reduce metal contaminants (biochemical processes). These processes can be used in-situ or ex-situ to aid the removal of metals from soils. This process is being adapted from the mining industry for use in the remediation of metal contamination.

Physical techniques

Physical separation is an ex-situ process that aims to separate the contaminated soil from the rest of the soil by exploiting certain characteristics of both the metal and the soil. These techniques are most effective when the metal is in the form of discrete particles in the soil. Physical separation is often used as a form of pre-treatment in order to reduce the amount of material requiring further treatment. Several techniques are available for the physical separation of contaminated soils including screening, classification, gravity concentration, magnetic separation and froth flotation.

Heavy metal extraction can be achieved by putting a solution containing extracting agents into contact with the contaminated soil (soil washing by chemical or physical treatment and in-situ soil flushing) or by electro kinetic processes. The contaminated fraction of soil and/or process water is separated from the remaining soil and disposed or treated.

4.4.2. Costs of the potential technical measures

These technical measures can be used for many types of contaminants but the specific technologies selected for treatment of Cadmium and Zinc will depend on the site-specific characteristics and the targeted level of contamination (acceptable risk). For more cost- effective remediation, two or more of these measures are often combined. The indicative costs of the individual remediation measures are summarised in the following table (Figure 25):

Target Indicative range of Technical remediation measures Application scale (1) compartments operating costs Isolation or sealing Soil and surface In-situ to isolate 0- 80 €/ Tonne (soil) water contaminated site Immobilisation by Soil and Limited polluted area 60 - 300 €/ Tonne solidification/stabilisation (Chemical groundwater 3 processes) 60 - 120 €/ m Immobilisation by vitrification Soil Limited polluted area 300 - 800 €/ Tonne (Thermal processes) (in-situ)

56

Target Indicative range of Technical remediation measures Application scale compartments operating costs (1) Chemical treatments Soil and Large area 150 - 450 €/ Tonne groundwater Biological treatments Soil – diffuse Low level of pollution, Long 45 - 75 €/ Tonne (Bioaccumulation, Phyto- pollution duration (bioremediation) remediation, Bioleaching or biochemical ) Physical separation (or soil Soil with high Small area (former site) 100 – 200 €/ Tonne exchange) concentration/risk Extraction (soil washing) Soil and Small area ~ 75 €/ Tonne groundwater (1) Source: adapted from Evanko et al. (1997) and CLARINET (2002).

Figure 25. Potential technical remediation measures and costs

Presently, the identification of potential measures to be undertaken is under investigation by stakeholders involved in the contamination management in the Kempen region (e.g. BeNeKempen and AbdK projects).

4.5. CONCLUSION

Heavy metal contamination is a serious threat for soil, sediment and water resources in the Kempen area. There is a clear need for a better understanding of contamination of the system as a whole. Various research and development activities are presently carried out in many interdisciplinary projects such as AquaTerra, BeNeKempen and AdbK projects.

In order to try to rationalise and integrate AquaTerra sub-projects research activities on the case study area, the DPSIR framework has been investigated for the issue of heavy metal contamination. The DPSIR implementation has an advantage to stress on the knowledge availability in terms of data, information and/or models. The knowledge throughout the entire DPSIR elements and relationships is concisely summarised in the following table.

DPSIR AquaTerra research & Non-AquaTerra research & Elements & Data & Information needed Knowledge in the case Knowledge in the case relationships study study D Quantification of historical and Available with Basin 3. Various information, e.g. from current emission of heavy Emissions from agricultural OVAM and Umicore in metals. sources are also studied (Flux Flanders, AdbK in the Characteristics of the socio- 2). Limited to the Dutch part of Netherlands. economic activities (e.g. area. industry, agriculture) P Heavy metal deposition on Limited to the Dutch part of Various studies. Mostly limited soil/ sediments and leaching area (Basin 3, Trend 3 and to small area and/or one sub- to surface and groundwater. Flux 2). system. S Assessment of concentration Studied for sediments and BeNeKempen project aims to of contaminant in soil, groundwater. Only the Dutch combine existing data and sediment and water system. part of the area. information. Special distribution of contaminant.

57

DPSIR AquaTerra research & Non-AquaTerra research & Elements & Data & Information needed Knowledge in the case Knowledge in the case relationships study study I Identification and No research of AquaTerra in Various studies, mainly quantification of impacts to this field focusing on human and different socio-economic ecosystem impacts. Former sectors, including ecosystem studies for the impacts on and human impacts. Cost of households. damages. R Identification of existing and No directly investigated in Currently undertaken by potential responses AquaTerra. General policy BeNeKempen responses investigated in EUPOL. D-P Integrated Mass-flux model Information available for soil Van der Grift and al. (2005). for soil, sediment and water. and lesser for sediment. No study made in the Flemish Long-term accumulation Dutch part only. part. model. P-S Empirical Models/ tools to Model developed in Flux 3 for Van der Grift and al. (2005). analyse effect of pressure on groundwater. Includes organic No study made in the Flemish the state of soil, sediment and pollutant. Dommel sub- part. water. catchement in NL. Hydrological modelling in Compute 2 at the small test- area. R-[DPS] Scenarios development of Trends of heavy metal in flood Scenarios construction at the pollution with respect to plain sediments under three case study level are missing. management measures. scenario (Biochem DSS, Physical efficiency of Basin R3.13). Limited to small measures in reducing D, P natural reserve area. and/or S. R-I Cost of remediation Integrator 3 (cost efficiency Research in other case measures. analysis). studies/ projects (e.g. Economic efficiency of Welcome, Alterra, Clarinet mitigation measures in projects) reducing impacts. Policy relevant, stimulated by the WFD.

Figure 26. Data and information needs and availability

REFERENCES

Albering J.H., S.M. van Leusen, E.J.C. Moonen, J.A. Hoogewerff and Kleinjans, J. C. S. (1999). Human Health Risk Assessment: A Case Study Involving Heavy Metal Soil Contamination After the Flooding of the River Meuse during the Winter of 1993-1994. Environmental Health Perspectives Volume 107, Number 1 January 1999.

Bardos, P., C. Mariotti, F. Marot, and Sullivan T., (2000). Framework for Decision Support used in Contaminated land Management in Europe and North America. NATO/CCMS special session, Wiesbaden, Germany.

CLARINET (2002). Remediation of Contaminated Land Technology Implementation in Europe. CLARINET report – Working Group 7. Available from http://www.clarinet.at .

Darmendrail, D., Cerdan, O., Gobin, A., Bouzit, M., Blanchard, F. & Siegele, B. (2004). Assessing the Economic Impacts of Soil Degradation. Volume II: Case Studies and Database Research Final Version, December 2004. European Commission DG Environment Study Contract ENV.B.1/ETU/2003/002.

58

Evanko, C.R. and Dzombak, D.A., (1997). Remediation of Metals-Contaminated Soils and Groundwater. Technology Evaluation Report TE-97-01. GWRTAC, Pittsburgh.

Görlach, B., Landgrebe-Trinkunaite, R., Interwies, E., Bouzit, M., Darmendrail, D. & Rinaudo, J.-D. (2004). Assessing the Economic Impacts of Soil Degradation. Volume IV: Executive Summary. Final Version, December 2004. European Commission DG Environment Study Contract ENV.B.1/ETU/2003/0024.

Gorree, M., W.L.M. Tamis, T.P. Traas, M.A. Elbers (1995) BIOMAG: a model for biomagnification in terrestrial food chains. The case of cadmium in the Kempen, The Netherlands. The Science of the Total Environment -168 (1995) p. 215-223.

Owens, Ph. N. and T. Edlman, (2003). SedNet – WP2, Sediment management at river basin scale. Minutes of river Dommel case study, SedNet second annual conference, 29 th – 30 th September 2003, Venice, Italy.

Sonke, J. E., Hoogewerff, J. A., van der Laan, S. R. and Vangronsveld, J. (2002). A chemical and mineralogical reconstruction of Zn-smelter emissions in the Kempen region (Belgium), based on organic pool sediment cores. The Science of the Total Environment, 292(1-2), 101-119.

Valstar, J., Wipfler, L., and Middelorp., P. (2005) Set of all relevant processes and data at the interface between groundwater and surface water for all sub -catchments studied. Chapter 3: Construction of conceptual model and relevant processes in the Dommel (Kempen). AquaTerra project – Deliverable Flux 2.1. van der Grift, B., Passier, H., Rozemeijer, J. & Griffioen, J. (2005). Integrated Modeling of Cadmium and Zinc Contamination in Groundwater and Surface Water of the Kempen Region, The Netherlands. Netherlands Institute of Applied Geoscience TNO - National Geological Survey, Utrecht, The Netherlands.

59

5. Ebro River Basin (Spain): soil and water salinisation

For further information, please contact Nina Graveline (BRGM) – [email protected]

5.1. INTRODUCTION – CONTEXT AND AIM OF THE STUDY

5.1.1. General context

Salinisation of water and soil are natural phenomena. Soil salinisation consists of the accumulation of soluble salts of sodium, magnesium and calcium in soils to the extent that soil fertility is severely reduced. Water salinisation is the presence in high levels of these ions in fresh water. Different causes, including natural activities, can explain the presence of high salinity levels in soil and inland waters. Nevertheless these phenomena can be exacerbated beyond their natural limits as a result of human activities.

In many semi-arid countries, salinisation is the main threat to water resources (Williams, 2001). Salinisation is a severe problem and has affected several places worldwide since the earliest days of civilization. Presently, it is estimated that between 80 and 110 million ha of irrigated land (i.e. between 34 and 47% of all irrigated land in the world) has been effected by salinisation to some degree (FAO, 1990). However the environmental and economic impacts of this process have not been quantified.

There are various potential anthropogenic causes of salinisation. Marine water intrusion has occurred in aquifers along the Mediterranean coast due to widespread groundwater abstraction, or potash or iron mining can result in leaching of large quantities of salts that reach both soil and water (diluted salt or tailings). Natural salinisation can occur in the presence of salt rich geology through erosion or the evaporation of salt-rich water on the soil surface

In Spain, the problem of salinisation is acute: 3% of the 3.5 million hectares of irrigated land is severely affected by salinisation, significantly reducing its agricultural potential, while another 15 % is under serious risk of salinisation 24 . The Ebro basin is particularly affected due to a combination of large, salt rich geological formations and intensive irrigated agriculture in an area that is one of the most important agricultural areas in Spain.

The Ebro basin extends over 85,000 km 2 in Spain and 300 km 2 in France (Figure 27)25 . The geological structure is characterized by high contents of evaporatic minerals (mainly halite and gypsum) present in the central Ebro valley around the region of Zaragoza. The high salinity levels in soils are due to the mobilization of salts from the subsoil via irrigation. In addition water dissolves the rock, increasing the levels of salts, which are then transported to the soil interface through capillary action. High salt loads are consequently present in the soil, in contact with crops and are also added with return flows from irrigation water. The inefficiency of irrigation systems (more water is applied than is needed by the crops) further increases this phenomenon and is exacerbated further in cases of reuse of highly saline water by agriculture, which concentrates salts through evaporation.

24 Montanarella communication available on www.lada.virtualcenter.org 25 See also the Characterisation of the Ebro basin – deliverable INTEGRATOR I.2.4c (Chapman et al, 2005)

60

90 80 70 60 50 40 30 TDS TDS t/km2/an 20 10 0

a a ia ld ro c c sia n b A Afri eri urope ea wor E m E Oc otal T North americaSouth a

Figure 27 Location of the Ebro river basin in Spain. Total dissolved salts exported from river basins to the sea in tons per square kilometer per year for different continents and Ebro (Data source: Meybeck, 1979)

5.1.2. Problem – Issue

Salinisation may affect both the ecosystem and the socio-economic system represented by the different water users in the basin. It is foreseen that the salinisation problem and its related impacts will worsen in the future. Integrated management should be considered to safeguard the soil-water system at the basin level.

Albiac (2005) states that there is an acute scarcity of information for both biophysical processes involved in non-point pollution sources and associated damage in Mediterranean agriculture. This implies that remediation policies and measures are neither relevant nor efficient. Indeed, improved comprehension of the phenomenon would enable calculations of its future economic damage taking into account the cost of the measures and their efficiency on the system.

5.1.3. Overall objective

The aim of this case study is (i) to describe the DPSIR scheme which is the common simplified representation used for Aquaterra project case studies and to use it to identify the economic activities that are responsible for salinity pollution and those that are affected by it; (ii) to produce an overview of the data necessary to assess the impacts of salinisation on different socio-economic sectors and ecosystems with respect to their current state, (iii) to outline preliminary trends in the evolution of salinisation in relation to changes in the main drivers identified.

This case study will present an outline for a possible way to develop an economic analysis of a contamination problem which is largely natural.

5.1.4. Link with other AquaTerra activities

AquaTerra activities in the Ebro basin deal mainly with the physical and chemical processes of the soil-sediment-water system. For instance, physical modeling is being developed to

61

analyze the fluxes of chemical substances such as TDS (Total Dissolved Salts) and individual minerals in different tributaries of the basin in order to make mass-balances of specific elements (FLUX sub project).

This work considered within a whole decision support tool could provide decision makers with an indication of where to focus efforts, both in terms of location and remediation strategies. In parallel the economic analysis can provide an assessment of the damage caused by salinisation to water users downstream. Finally an economic assessment of the benefits and costs of remediation measures would provide valuable information for decision makers within the basin.

The workshop held in Barcelona to launch the Ebro case study by gathering experts’ views of the Ebro River Basin, has not contributed much to the present work as the geographical scale was poorly adapted (most people were concerned by the inland basins of Cataluña outside the Ebro basin).

Nevertheless, besides salinisation, the major issues identified by the audience at the workshop were: (i) Water is nearly free and the irrigation price does not cover the “full cost”: this is a reason for the inefficient use of water in the basin and the misuse of water by the agricultural industry as a whole, for whom water prices are not deterrent; (ii) The most urgent action required with regard to water scarcity is to stop agricultural land extension (irrigation plan), more than improving irrigation techniques (Chapman et al. 2006).

5.2. STATE OF THE WATER: SPATIAL AND TEMPORAL VARIABILITY OF SALINITY IN THE EBRO BASIN

The state of the Ebro water system (surface and ground waters) can be defined according to the following “salinisation” indicators:

- Total Dissolved Salts, TDS (in mg/L);

- Conductivity EC (dS/m or µm/cm);

- Chloride (Cl -) concentration (in mg/L);

- Sulphate concentration (in mg/L).

It should be noted that chlorides are naturally present in all surface waters; the concentrations are generally lower than 10 mg/L or even 1 mg/L. In groundwater chloride concentration can reach a few grams per litre. Freshwaters have concentrations of less than 150 mg/L (in Cl -) and saline waters have concentrations greater than 10,000 mg/L.

5.2.1. Surface water

The River Ebro is 910 km long and crosses nearly the whole of Spain from North West to South East, from its source in Cantabria to the Mediterranean Sea in the South of Cataluña. The main western tributary is the Jalon (224 km) and the eastern tributaries coming from Pyrenees are the Aragon, the Gallego, the Arba, the Arga and the Segre. They are characterized by high flows with a seasonal variability. Mean discharge of the Ebro can reach 263 m 3/s in Zaragoza.

Salt content increases along the River Ebro: chlorides and sulfates are the main ions present that contribute to salinity. The chemical composition of rivers indicates that the salinity is the

62

result of halite and gypsum rocks in the basin (Isidoro, 1995). The problem is greatest in Aragon and Cataluña (Chapman et al., 2005).

Water quality is also very variable through the year as the concentration of salts depends largely on river flow and the agricultural activity. In low flow periods, the concentration of salts and contaminants increases significantly, but loads are highest during the runoff period (as irrigation return flows are gathered by tributaries). In the lower Ebro, where water return flows from the entire River Basin are collected the mean conductivity is about 1,000 µS/cm, which is higher than the limit recommended by the European Union for pre-drinkable waters (Directive 75/440/EEC).

Alberto et al. (1986) made a water and salt balance in the Ebro basin for the period 1974- 1979 and showed that tributaries from the eastern side of the Ebro basin contribute 90% of the salt load. This is due to a larger extension of territories (58%), higher precipitation (65%) and more irrigated areas. Among the five principal Ebro tributaries, the Cinca, Segre and Aragon rivers have a diluting role whereas the Arba and Arga rivers contribute with above average salt concentrations.

5.2.2. Groundwater

Groundwater is also affected by salt problems in the Ebro basin. The extent of salinisation is partly 26 given in Figure 28. The most affected groundwater body is the Ebro depression, which includes the large alluvial aquifers of the basin where the mean salinity reaches 3,200 mg/L (median 1,200 mg/L) 27 . Mean hardness of water is about 75°F. The sulphat es are the main salt ions present in the central Ebro depression followed by chlorides, bicarbonate, sodium, calcium and magnesium. These levels would induce limitations on water use for drinking purposes. Other groundwater resources of the Ebro basin have lower mean mineral contents as their contents have a greater influx of water from rain in the Pyrenees, but they can have sporadically high salt contents due to local geology (CHE, 2004).

The WFD basin characterization 28 identifies the salt issue as being a major point-source pollution problem for groundwater. Critical points are identified are in Miranda de Ebro (provincial de Burgos), Merindad del Rio Ubierna (provincial de Burgos), Pamplona (Navarra) and Noain (Navarra) 29 . It would be of great value to know if the salt affected groundwater communicate with downstream river waters and particularly with those in the Ebro depression.

26 Only the points that are monitored within this network 27 Mean of 2,200 µS/cm and median of 1,400 µS/cm 28 Available at www.chebro.es 29 Greenpeace communication Agua - La calidad de las aguas en España-Un estudio por cuencas available at ww.rivernet.org

63

Figure 28 Conductivity in groundwaters in the Ebro basin (source: www.chebro.es)

5.3. DRIVERS AND PRESSURES

Drivers are defined as being the activities or natural elements which are the sources of salts. Drivers and related pressures contributing to water salinity are various. Overall salt concentrations are very high due to various emissions which might individually not be a threat to water quality. Partly it is the result of natural phenomena. Anthropogenic behavior both increases these effects and, independently from natural conditions, leaches considerable amounts of salts. The following descriptions and analyses are mainly qualitative. When possible, quantitative figures are given in order to be able to compare the effects of different drivers.

Potential anthropogenic sources include all activities that (i) use salts as a raw material or (ii) that produce salts as a by-product or as a final product. In some cases it can be assumed that some effort will be made to minimize losses to the environment and recycle components when economic conditions are a deterrent (recycling of residues or purification to minimize salt levels). Behaviors to limit pollution will also largely depend on the type of mineral and its economic value.

The analysis within this case study is limited to the potential emissions of chlorides and sulphates in the environment.

5.3.1. Natural contributions

Salts (presents in different forms - sodium chlorides (NaCl), potash chlorides (KCl) and calcium chlorides (CaCl)) in general are naturally present in this river basin.. The natural presence in water of chloride ions is largely due to water leaching through salt rich rocks and soils. Sodium is one of the main components of the earth’s crust and is present in all waters as its salts are very soluble and sulphates can be present in iron deposits and are characteristic of gypsum (CaSo4 · 2H2O).

The Ebro basin geology is characterized by the presence of both halite (main geological formation in the area – NaCl) and gypsum, two types of salty rocks which are responsible for the natural presence of salt in water after the dissolution of evaporites (rocks formed from the

64

evaporation of old inland lakes or seas). Other significant geological features are the hypersaline lakes of the central Ebro basin in the Monegros area: there are 111 natural depressions, of which about 16 are inundated seasonally. In the past these saline areas were used as a source of salt for human consumption30 .

Soils of the Ebro basin also have saline characteristics. Both aridisols (arid moisture regime) and xerosols (Figure 29) are present and contribute to water salinisation by leaching.

Soil salinity may also have an impact on agriculture and an important role in the water salinisation phenomenon. According to Alberto (1986) (quoted by Causapé (2003)) more than 300,000 ha of soils could be affected with salts in the Ebro basin.

Figure 29. Xerosols among soil types in the Ebro basin: Xerosols are in blue (others: cambisols in brown, vertisols in dark pink) (source: EEA, soil map of Europe, 2005 31 )

Thermal waters also exist in the Ebro basin. They are exploited for medicinal purposes as a result of their high salt content. An inventory has listed 314 sources, of which 22 have concentrations above 2g/L of salt 32 .

5.3.2. Diffuse pollution from agriculture

Irrigation represents about 90% of the water use in the Ebro basin. The irrigated land has been developed over the last 2,000 years and covers more than 784,000 ha. It is expected that irrigated areas will increase in the future. The current irrigated crops include alfalfa, winter cereals (barley and wheat), maize, vegetables, sunflowers, fruit trees (apples and peaches), horticultural crops and rice (mainly in the delta). Vineyards also occupy a significant area of the basin (2% of the total agricultural area, mainly in Castilla La Mancha and La Rioja). Almost no crops, except winter cereals with poor yields, could be grown without irrigation in this geographical area.

The salt contribution of agriculture can vary according crop type and location. Agriculture emits chlorides and sulphates through the use of fertilizers (like other minerals - potash, calcium, magnesium - that are provided by fertilizers). Sulphates are largely used by vineyards, while breeding produces chlorides and sulphates (from manure). These contributions of minerals are not specific to the Ebro basin and a detailed assessment has

30 Valero Garces available at 31 Available at http://www.eea.europa.eu/ 32 www.chebro.es

65

not been undertaken. A more specific contribution of agriculture in the Ebro basin is the leaching of natural salt from agricultural land through irrigation.

Figure 30. Irrigated areas in the Ebro basin (in grey), 783,900 ha in total (source: CHE, 2005)

There are two types of irrigated lands: small entities for which irrigation is organized individually and large irrigated perimeters, where irrigation management is made by communities (“communidades de regantes”). This differentiation is important to understand how agriculture can change. An irrigated farm belonging to a large perimeter is not able to stand alone on the issue of a change of irrigation technique for instance. Those changes are mainly driven by community agreements. In addition, large irrigation systems depend on the supply of large water supply canals 33 . The main irrigation systems are Lodosa, Tauste, Imperial de Aragón, Delta (margen derecha y margen izquierda), Bardenas, Riegos Del Alto Aragón, Aragón y Cataluña, Urgel and Najerilla.

Name of the canal Area (ha) Name of the canal Area (ha) Canal margen derecha del Ebro 15.170 Sistema Monegros II 800 Canal margen izquierda del Ebro 12.690 Canal del Cinca 42.600 Canal margen derecha del Najerilla 2.785 Canal de Bardenas I (Bardenas) 56.952 Canal margen izquierda del Najerilla 5.015 Canal de Bardenas II (Bardenas) 3.749 Canal Imperial de Aragón 26.508 Canal de Aragón y Cataluña - zona alta 54.046 Canal de Lodosa 28.888 Canal de Aragón y Cataluña - zona baja 44.156 Canal de Lodosa (riegos de invierno) 3.930 Canal Auxiliar de Urgel 23.500 Canal de Tauste 9.022 Canal de Piñana 13.495 Sistema Monegros I 32.664 Canal principal de Urgel 51.500 Canal del Flumen 22.115 Canal principal de Urgel (riegos de invierno) 5.796 total large canals : 455.381 ha

Figure 31. Importance of large irrigation systems in the Ebro basin : 58% of the total irrigated area (source: www.chebro.es )

33 Canals have also secondary uses (drinking water and industries, mainly production of electricity) that must not be forgotten even if less important in terms of quantities.

66

Agriculture in the Ebro basin exerts an indirect pressure on the water quality and salinisation problem. Irrigation dilutes salts in the saline rich soils and in the subsoil. It subsequently transports them by leaching to downstream waters (ground- and surface waters). Thus irrigation “exports” the salt water to wider areas than those naturally affected. This phenomenon is directly linked with the quantity of water used for irrigation because: (i) the more water is used the more salt dilution occurs (ii) pools of stagnant water caused by over irrigation or lack of drainage is evaporated, leading to concentration of salts in the soil until it precipitates, and (iii) evaporation increases the uptake of saline water from the subsoil (when a saline substrate is present) or even the rising of the water table.

In the central Ebro these processes are acute for three reasons:

(i) The climate: potential evapotranspiration is very strong 1,300 to 1,400 mm/year in comparison to an average rainfall of 400 to 500 mm/year;

(ii) Socio-economic reasons: intensive irrigated agriculture;

(iii) The extent of salt affected soils (about 300,000 ha: Alberto, 1986 quoted by Causape, 2003).

Consequently, irrigation return flows are an important factor affecting the salinisation of water in the central Ebro region although water used for irrigation is generally of good quality from the perspective of salinity (water from the Cinca, Monegros, Aragon y Cataluña and Bardenas canals have a water conductivity in the range of 0, 2 -0, 4 dS/m).

Causapé et al. (2004) estimated salt drainage loads from agricultural areas to be relatively high, from 4 t/ha/year in areas with a relatively low presence of salts in the substrate to more than 15 t/ha/year in geologically saline areas. This is explained by high drainage fractions (37-57%). For a given soil type, a significant link could be established between irrigation efficiency and salt loads per hectare. The other determinant affecting salt loads is the salt fraction in soil. They concluded that irrigation efficiency was the main factor that could minimise saline contamination from agriculture fields.

Factors influencing the irrigation return flows (high salt losses) are largely those that contribute to irrigation efficiency. According to a range of studies (Causapé and Claveria et al., 2004; Causapé et al., 2006; Playan, 2000; IEEP, 2000 and Causapé, Auqué et al., 2004) these include:

• The cropping patterns;

• The irrigation technique and management 34 (which are parameters influencing the drainage fraction, but that are very little flexible)

• The irrigation time and period (flexible parameters influencing the drainage fraction).

• The nature of soil (amount of salts present in the sub soil) and the land leveling;

• The climatic characteristics of the year;

• Climatic conditions management (taking into account wind for aspersion for example);

34 Water transport systems water (canals and urban networks) loose about one third of the water. (CHE, 2005 (1))

67

Drainage systems of the irrigated perimeter type lead return flows from agriculture to the Ebro tributaries and ultimately to the Ebro river. The major irrigation technique used was gravity irrigation. In order to have better water productivity and irrigation efficiency, irrigated land is being modernized progressively. Drip irrigation and/or aspersion equipment are installed on fields. The decision of to change irrigation technique depends on economic conditions (cost, return on investments time, price of water 35 , public incentives) and technical conditions (crop requirements, land characteristics and possibilities of change according to the infrastructure for example).

5.3.3. Industrial sources of pollution

Within the industrial sector, two types of salt sources causing contamination can be distinguished:

- Direct discharges into the water system that increase salt concentration in surface waters. These discharges are often not continuous in time;

- Indirect discharges of salts through the dissolution of solid salt residues that can reach both ground- as well as surface waters;

Salt mines

Among mines that produce saline water are salt mines (dissolution), potash mines, coal or lignite mines (coal cleaning), iron and pyrite mines. Several operating and former mines are present in the Ebro basin. The most important are:

• The salt mines of Remolinos (principal mine is the "María del Carmen" mine) are located 35 km North-West of Zaragoza. The salt deposits are included in a Miocene lakeside formation which occupies the eastern side of the Ebro River. This deposit is exploited by the company “Iberica de Sales” who extract about 240,000 t/year. The main part is extracted directly and is used for road deicing and for animal consumption (breeding). Another part is dissolved with water and transferred to “Salinas” where brine evaporates: this salt is used for human consumption (about 14,000 t/year).

• The salt mine of Beriain y Las Arrubias located in the Sierra de Nuestra Señora Del Perdón (Cendea de Galar) near Pamplona (North-East of the Ebro Basin) is exploited by Saldosa S.A. Extraction is done with water and humid salt is sold for the chemical industry. Alimentary salt (contents less than 0.1% humidity) is also used for decalcification and electrolysis systems for swimming pools. Previously a potash deposit was exploited on the same area and had since been abandoned. Residual potash mine water can contain up to 300g/L of chlorides.

• Crimidesa, S.A. exploits a deposit of glauberite and produces 500,000 t/year of sodium sulphate in Cerezo de Río Tirón (province of Burgos). Uses are various: from detergent fabrication to paper, textiles and steel-manufacturing processes.

• Iron mine of the Menera Sierra is located in Ojos Negros (Teruel): production stopped in the 70s but the impact could be still present.

35 Enabling stating the benefit from reduce consumption per hectare

68

Other salt mines exist in Spain (Alicante, Barcelona, Baleares, Huelva, Almeria, Cantabria) and the national production is 3.8 million t/year (of which 66% from salt deposits -potash and halite- and 34% from marine sources) (Estadistica Minera España, 2002).

No information concerning the impact of these activities has been found in the literature. Discharges of these sites are not registered in the European Pollution Emission Register (EPER)36 database, which reports discharges over 2000 t/year (see next section). Thus, it can be assumed that chloride discharges from these mines are less than 2,000 t/ year each 37 . Nevertheless such activities can have a significant impact such as they do in France (Alsace), where the old potash mines (KCl) have caused a large salt plume in the Alsatian aquifer. Today exploitation has been stopped but decontamination of the aquifer is in progress at significant expense. Consequently it is likely that these activities in the Ebro basin will have impacts on water resources.

Salt industrial discharges

In the Ebro basin, the two main industrial areas are the region of Zaragoza in the central area and the province of Alava around Vittoria in the North West.

Sodium chloride is largely used in chemical industry in order to produce chlorate, caustic soda and hydrogen. Sodium chloride is also used in industrial water softeners. A lot of chlorides are released in waste, although industries must recycle waste water according to economic and regulatory constraints (i.e. cost of release / recycling / raw material price). These industries may also, in the case of an accidental incident, emit salts.

The second type of activities that generate salt residues are generally those that require high quality water for their processes with low hardness and low salinity. They employ a process to reduce salt concentrations in water, which traditionally is made with ionic interchange resins (strongly cationic). This process generates large quantities of salt residues/effluents. Disposing of these residues with important volume of residual water increases its conductivity up to 1,500-2,000 µS/cm. This leads to inappropriate water quality for recycling it within the plant process or even for agricultural use. Examples of such industries are the textile industry, the paper industry, the warming and cooling industry, and the agro-food industry. Figure 41 in part 5.4 shows several figures of quality requirements by industry, which indicates which ones are responsible for salt emissions due to their high quality requirements.

Evaluation of quantities of chlorides emitted in the Ebro basin waters

According EPER data Spain is the European country with most important direct chloride waste discharges to surface waters with 7,659,420 tons of chlorides in 2001 (46% of total European Community).

The checking of the EPER database concerning the Ebro basin states that more than 1,000,000 tons per year are emitted directly to the Ebro River Basin.. Chloride is the only parameter contributing to water salinity registered in this database. Only industries with discharge loads of more than 2,000 tons per year of chlorides discharges are registered, therefore figures are an underestimate.

36 http://www.eper-es.es/ and the European register www.eper.cec.eu.int 37 EPER database do not take into account sulphates. Also the old industrial sites are not considered.

69

Figure 32. Location of industries register in EPER with chlorides emissions for 2004 in the Ebro basin (Lila area) (source : )

In the Ebro basin, chlorides emissions are mainly due to combustion plants (about 90%). Chemical industries (organic and inorganic) represent the majority of the remaining 10%. It is likely that major emissions of chlorides in the environment correspond to waste from water treatment (following high quality requirements of industries).

Historical point-source pollutions

An inventory of these sources in the Ebro basin has identified two “black spots” with saline impact on groundwater in the western part of the Ebro basin . These are located in Miranda de Ebro and Merindad del Rio Ubierna (both in the province of Burgos). They are related to partly abandoned large industrial and mining areas (in the case of the Miranda de Ebro) 38 .

5.3.4. Road deicing with sodium chloride

In winter, salt is largely used to deice roads. In the Ebro basin, several roads are located at high altitude (Pyrenees and Sierra Menera) and require deicing in winter.

On the world scale the use of salt for road deicing is considerable: it varies between 8 and 15% of total consumption and these quantities are emitted directly into the environment. France uses 1 204 000 t of salt yearly (sodium chloride in 1996 39 ). Considering the surface of the Ebro territory, it is estimated that 180,000 tons per year would be spread on the roads within the Ebro basin (pro rata from France figure). These salt loads may directly affect soils and waters.

5.3.5. Waste water treatment plant residues

Salt sources in the sewerage network are many and various: chloride in human urine, sodium chloride used in domestic dishwashers and water softeners and industries connected to the public network. Generally salts are not treated in waste water treatment plants, but in certain cases due to particular discharges (industrials for instance) waste water treatment plants could treat salts. Waste water treatment processes as coagulation and ion exchange require the use of products containing minerals. Therefore these processes contribute to

38 Greenpeace communication Agua - La calidad de las aguas en España-Un estudio por cuencas available at ww.rivernet.org 39 http://www.106.us/f/chlorure_de_sodium/index.htm

70

increase salinity through sodium, sulphate and chloride releases 40 . In order to assess the salt contribution from waste water treatment plants, mean wastewater discharges data would be required.

5.3.6. Atmospheric contribution

Some standard data enable an estimate of the salt contribution by atmospheric deposition. Higher bounds correspond to oceanic regions deposits.

Atmospheric deposits (in kg/ha/an): total deposit (min.-max.) Sulphur /sulphate (S-SO4) 5,3 - 47,5

Chlorides (Cl) 5,5 - 436

Figure 33. Atmospheric deposits - Source : École des mines de Douai - Audition du 20 février 2002 dans qualité de l’eau en France

Without any oceanic contribution, the rate of chlorides in rain water is about 2 to 3 mg/L. Taking evaporation into consideration it has been estimated that the contribution to aquifers is about 6 mg/L. These contributions are classified as atmospheric deposits. Taking the lower value of Figure 33 the estimate for the Ebro basin area would be about 100,000 t of chlorides and sulphates (about 50% each).

5.4. IMPACTS OF SALINITY

The aim of the following part is to describe, and if possible quantify, the impacts of water salinity on water uses. Quality requirements in terms of salinity parameters are necessary to estimate impacts and eventually adaptation strategies (implying costs). The spatial dimension is necessary because water quality is very variable: in the Ebro basin upstream surface water users are generally not affected by salinity whereas users from the central part of the Ebro (around Zaragoza) to the delta are affected by high salt loads. Some more upstream points also suffer from saline pollution. The alluvial groundwater corresponding to the Ebro depression is also affected (see the part on State of the water 5.2). The poor quality of Ebro water was an argument used against the transfer of Ebro waters foreseen by the Hydrological National Plan (PHN: Plan Hídrologico Nacional), because it would not have made sense to transfer water that would be improper for most uses. Cost of transferred water would have been to high as it would require treatment due to the high salt levels (among other issues) (Arrojo 2002). The argument was that water could only serve for irrigation with limitations on yields and crops and constraints on drainage in order to limit salinisation of soils 41 .

Agricultural water demand is far and away the highest in the Ebro basin, representing 90% of the total. Urban demand represents 7% while industry represents only 3%. Water flow is largely used to produce energy mainly on tributaries from the Pyrenees.

40 http://www.cnrs.fr/cw/dossiers/doseau/decouv/potable/traitEau.html 41 Jose Lluis Naredo on www.rivernet.org/Iberian/deltaebro/savethedelta_s.htm

71

5.4.1. Impacts on ecosystems

Plants and animals show a wide range of tolerance to chloride and some, which live in saline lakes, may be resistant to very high concentrations. High levels of chloride discharged into freshwater bodies may be harmful to fish and other aquatic organisms which are not adapted to saline environments. Some terrestrial plants and animals may also be sensitive to chloride and be succeeded by those that are more tolerant. In the Duero basin (in the South of the Ebro basin) the disappearance of wetlands has occurred in parallel with salinisation of soils.

Parameter Impact and thresholds Conductivity Rapid change in conductivity can kill cells (fishes) Critical for aquatic ecosystems above 3000 µS/cm Sodium Toxicity: CL50 for Epinoche at 0,5mg/L Sulfates Algae growth requires > 0,5 mg/L Animals : troubles from diarrhoeas to death for rates from 2100-3590 mg/L Chlorides Prevents vegetation growth from 0,2-0,4 g/L an “excessive presence” is toxic for fish and aquatic fauna

Figure 34. Threshold for salinity parameters and their impact on ecosystems (Bremond 1979)

Indirect effects of salinity in water may occur from the combined effects of salinity and other water quality parameters. Available information suggests that the effect on aquatic biota of an increase in salinity alone is less than the effect of an increase in both salinity and nutrients. Additionally, nutrients have been shown to inhibit salinity tolerance (Kefford 1999). Furthermore, if lead is also present in saline water, some insoluble salts can be formed (sulphates and carbonates) which may engender extra impacts on the ecosystem i. It would be reasonable to expect similar types of processes to occur in wild aquatic plants. High salt levels must have an impact on both fauna and flora, but the biological effect of saline water cannot be extrapolated from knowledge of the effect of salinity alone.

As there is no significant presence of any animals or vegetation in groundwaters no considerable “valuable damage” on the ecosystem is considered. Ecosystems impact could be assessed by non marketable values but this would require a special methodology to be elaborated.

5.4.2. Impacts on the drinking water sector

Norms and requirements

EU standards of conductivity, chloride, sulfates and sodium on drinking water and prepotable waters are presented below:

72

Water drinking norm Prepotable limits - Directive Guide (mg/L) - Directive 75/440/EEC value 98/83/EC

A1 Type A2 Type A3 Type

Conductivity at 20°C 2500 1000 1500 2500 1000 (µS/cm =0,001dS/m)

Chlorides (mg/L) 250 200 250 350 200

Sulfates (mg/L) 250 250 250 250 150

Sodium (mg/L) 200 10 - 115 mg/L « acceptable thresholds » (Bremond 1979)

Figure 35. Norms and guideline for salinity parameters in drinking water

Corrosion problems

High salt loads can lead, according to the type of minerals present in water, to corrosion of cement and metals. Light corrosion might be an advantage by “cleaning” tubes when corrosion is constant and moderate. Significant levels of corrosion may imply a more frequent renewing of tubes. This would represent a significant cost (Abdul-Kareem Al-Sofi 2001),(Barberon, Baroghel-Bouny et al. 2005). Another problem is that water that causes corrosion becomes charged and can be “dirty” by the standards of the drinking water industry. High mineral rates in water can also affect users through hardness problems due to carbonates and sulphates.

Taste requirements

Salinity shall comply to organoleptic water criteria such as taste. Concentrations of less than 1,000 mg/litre (1.56 dS/m) are normally acceptable to consumers.

Nominal taste threshold are as follows, but taste is a subjective judgment therefore the level of salts at which a ‘taste’ becomes apparent will vary with the individual:

- Chlorides 400 mg/L;

- Sodium sulphates 200-500 mg/L;

- Calcium sulphate 250-900 mg/L;

- Magnesium sulphate 400-600 mg/L;

The maximum total salt tolerance is 0.1 to 0.5 g/L.

Health impacts

Conductivity should remain, according to the World Health Organization, under 500 mg/L total salt (extreme limit by 1,500 mg/L). However for the majority of the major ions, no health guidelines have been derived. Present guidelines are based on taste and other side-effects of individual ions, such as staining of laundry by iron, or the rotten egg smell of sulphates water (Tanji 2002). Water with high values has laxative effects and can cause diarrhea (especially in alkaline waters) and are to be avoided by people suffering from cardiovascular

73

or kidney diseases. Consumption of highly mineralized water should only be administrated with a therapeutic objective. Chlorides can rise to 700 mg/L without any significant effects.

Impacts for the Ebro water drinking sector

In the Ebro basin surface water would be more and more often inadequate for drinking water uses because quality values exceed pre-drinkable water norms (European standards directive 75/440/EEC). However, as the level of sulphates in surface water is naturally elevated (geology naturally rich in sulphates), the abstraction of water containing sulphates concentration above drinking water guideline levels is tolerated at specific sites.

The main problems for water drinking companies are caused by the sulphates and total conductivity; chlorides seem not to be mentioned. 23 surveillance points from the 146 monitored for raw drinking water control (Article 7 of WFD) exceed the limit for sulphate ions. They are located in the central Ebro depression around Zaragoza. Tributaries affected are the Guadalope (with very high concentrations up to 1,000mg/L), the Matarraña and the Segre rivers. The main problems and highest values occur in summer. Nearly all points are located in the defined water bodies that are “at a high concentration due to natural sulphate conditions” with the exception of 3 points: ‘Segre in Granja de Escarpe’; Huerva en Maria de huerva’ y ‘Canaleta en bot’, where high levels might be due to other sources than natural conditions (CHE 2005).

The main drinking water providers affected by sulphate are the Zaragoza water production company (635,000 inhabitants) and the Consorci de aguas de Tarragona (394,000 inhabitants). Data on frequency of threshold exceeding on sulphates enable to calculate that 25% 42 of the time the 1,100,000 inhabitants supplied by affected waters are supplied with non-potable water (>250 mg/L). The large majority concerns surface water, only 11,000 inhabitants are concerned with groundwater but they are affected by exceeding of thresholds more frequently (45% of the time).

According the CAT (Consorti de Aiguas de Tarragona) water quality with regard to salt is not a real problem; at least it does not engender extra cost. Consumers would not be affected from these high loads of salts (from a taste point of view as well as health concerns). Corrosion was neither cited as a problem, and does not seem to represent a cost at present.

Zaragoza drinking water company abstracts water from the Ebro at two points: one on the Ebro itself and the other on a side channel of the canal imperial de Aragon. Excessive sulphates concentrations oblige them to request a derogation which engenders extra administrative costs. Salts are not treated and until now the only alternative solution would be to turn to another water source 43 .

The impact of saline water and extra costs are not notable in the drinking water sector today, but they may become so in the future if salinisation increases. In for the case of water exceeding 2,500 µS/m at 20°, 250 mg/L chlorides or 250 mg/L sulphates, available treatments are reverse osmosis, reversible electro dialysis, ionic interchange, partial decarbonation. The choice of technique depends on the particular substance involved. One example in Spain is the case of the Aguas de Barcelona Company which abstracts water from the Llobregat River and which is intending to develop a large salt treatment plant to treat the waters. Ultra filtration and reverse osmosis are the likely options to be chosen for this project: the investment costs are 16 and 24 million €. Energy costs represent about 25% and operational and maintenance cost about 30% of total yearly costs (Global Water

42 This has been calculated from the quality monitoring data reported in the CEMAS. Informe de situacion año 2005. CHE

43 Plan de mejora de la gestion y calidad del abastecimiento de agua (2002) -Ayuntamiento de Zaragoza http://cmisapp.zaragoza.es/ciudad/grandesproyectos/plan_mejora.htm

74

Intelligence 2006), but this proportion is likely to reduce as techniques are refined. Costs of treatment of brackish water would be around 0.18 €/m 3 (0.36-0.39 €/m 3 for sea water Arrojo 2002). They may appear in a future scenario. At present, if the water was treated when quality exceeds thresholds it would represent about 5.5 million €44 (a cost that would be probably born by consumers).

5.4.3. Agriculture

Agriculture is highly developed in the Ebro basin and is the most important economic sector of those activities directly related to water (others being water services, energy production and water tourism). In 2002 it generated 2,305 million €1995 (CHE 2005). Agriculture is also the sector most affected by salinity. Two types of effects have to be distinguished:

- On-site effects:

Salinity in the root zone increases osmotic pressure in the soil water and forces plants to exert more energy in taking up soil water to meet evapotranspiration requirements. Despite the fact that the quality of irrigation water is relatively good given the nature of the region (Causape, Quilez et al. 2004), the levels of salts in soil water are very likely to affect crop performance. However it is not possible to assess or estimate the quality of the water as absorbed by the crops Information on the quality of water content in soil would enable stating the relative impact of soil salinisation on crop growth.

The economic impact of salinisation on agriculture has been evaluated by some authors (see Figure 36). The cost varies between 140€ and 810 €/ha for the on-site effects of salinisation.

Place and extend of the Water quality Cost estimation Sources quoted by case study (soil extract) (Causapé 2003)

-1 Gallego catchment 2 dS.m 300,000,000 pesetas 1988 (Albisu 1988) (13 000 ha) ~140 €/ha

Bardenas I - Arba - 135,000 pesetas 1989 / ha (Zekri and Albisu 1993) catchment (56 760 ha) 810 €/ha

Figure 36. Cost evaluation of on site effect of salinisation in agriculture (cost is beard by farmers)

- Off-site effects

Off-site effects are losses in agricultural productivity due to the use of high salinity level irrigation water from surface or groundwaters (return flows from irrigated land diluted to some extent with less saline water). The systems present along the Ebro River around Zaragoza and downstream are those most affected by the off-site effects of salinisation, as water used for irrigation is enriched by return flows.

For both on-site and off-site effects, the biggest impact is a loss of yield, the costs of which are born by farmers. When these effects are very pronounced it is no longer possible to successfully cultivate the land, or at least drastically reduce the range of crops it is possible to cultivate, a position that could result in land desertion. Ultimately the land can become so severely degraded that it is not suitable for any crop and the structure of the soil is destroyed

44 Taking the number inhabitants and the frequency of sulphate exceedance (25% for 1100 000 inhabitants), applied to the mean urban consumption per inhabitant for the Ebro basin of 115 m3/year (basin characterisation, CHE)

75

due to an excess of sodium. Very little information has been found on land desertion in the Ebro basin, but the conclusion of a literature and Internet review is that this phenomenon is relatively insignificant in the Ebro basin at present, although there is a precedent in Australia, demonstrating that this scenario is a genuine possibility.

The adaptation of agriculture to increasing salinisation (Figure 37) will engender different types of costs depending on the nature of each adaptation and the intensity of the problem. Protective work or actions such as installing drainage tubes to reduce water stagnation, which favours evaporation and concentration of salts on the soil, are one potential adaptive measure. Corrosion of certain installations (irrigation equipment) may occur and engender extra costs due to more frequent renewal of materials or the use of reactants to maintain the quality of equipment. Neither drainage installation nor early degradation of materials has been identified in the Ebro basin, but this would need to be to confirmed locally with farmers.

Figure 37. Adaptation of farmers practice with increasing salinity and according net income per hectare of crop.

Other effects from salinity have been identified from a literature review:

Conductivity - Good quality until 750 µS/cm - Between 750 and 1500 µS/ cm depends from ionic composition, above water is not usable for irrigation Sodium - Toxicity >7000mg/L for chicks and > 2000mg/L for game - Aspersion can cause concentration on leaves and cause defoliation Sulfates - N o problems <200 mg/L - Animals : troubles from ditherers to death for rates from 2100-3590 mg/L - Recommended drinking water for animal should be < 1000mg/L Chlorides - I mpacts on vegetation growth above 200-400mg/L - D rinking for animals 200-400 mg/L

Figure 38. Table of effects for agriculture (Bremond, 1979)

The main impact on crops is a reduction in yield. Estimates for two irrigation systems have been made:

• Evaluation of the cost of off-site effects of salinity on the Tauste community (23 900 ha)

76

The first step was to develop functions linking quality of water to yield. For this aim data of (Darmendrail 2004) and (Cuartero and Fernandez-Munoz 1998) had been used. Linear functions were developed for corn, barley, tomatoes, and alfalfa, while a polynomial function was developed for wheat. Barley is very resistant to conductivity whereas tomato plants start to suffer from low concentrations of salts. Above 2 dS/m the impacts of salinisation on tomatoes, corn, wheat and alfalfa start to be considerable.

120 100 o at lfa om lfa 80 T A rn Co 60 eat Wh 40 y % yield loss e Barl 20 0 0 2 4 6 8 10 12 14 EC (ds.m-1)

Figure 39. Relative yield losses for wheat, corn, alfalfa, tomatoes and barley according conductivity levels of irrigation water expressed in dS.m-1

Data on crop areas were gathered on the Tauste community for two systems (i) Canal imperial de Aragon and (ii) Canal de Tauste, whose waters are largely affected by salinisation as a result of collecting an important part of the return flows from irrigation. Alfalfa, corn, barley, wheat and tomatoes have been considered, as other crops are less sensitive to salts 45 . Irrigated land on the Comarca de Tauste extends over 23,900 ha, 14,400 ha on the canal Imperial and 9,500 ha on the canal de Tauste. The distribution of crop types on the irrigated area is shown in Figure 40. 70% of the area is occupied by the 5 crop types for which loss functions were constructed. Data on water quality was then used to assess the relative yield loss per crop. These yield losses were then multiplied by the market price 46 for each crop. The quality of absorbed water by plants has been supposed to be equal to that of the irrigation water (which is an underestimate as evaporation should increase the conductivity of absorbed water). Irrigation water quality has been taken from Causape et al. (2004) who quote a value of 2,2 dS/m in Tauste, where the impacts of the very large Bardenas irrigation return flows have an important impact on both the Ebro and the irrigation channel water quality.

45 The crop areas had been taken from GIS information portal on www.chebro.es as well as the repartition of the area among crops for year 2004 46 yields and prices data were gathered from www.chebro.es - Encuesta sobre superficie y rendimientos del año 2005- and www.mapa.es

77

Wheat 8% Other crops Alfalfa 10% 23%

Barley 3%

Sunflower Corn 11% 33% Vegetables 12%

Figure 40. Distribution of irrigated crops on the Tauste community

Using the functions established previously, water of this quality would result in the following yield losses relative to standard recorded yields in the region: wheat 10%; corn 6%; alfalfa 1%; tomatoes 22%; barley 0%.

Crops vary in their sensitivity to salinity and the cost of increased salinisation to the producer will largely depend on what they grow. Applying these yield losses to the Tauste area gives a total loss of: 6,400,000€ 47 which corresponds to a loss of 271 € / ha and a relative loss of 15% on the product (yield*price).

These numbers are not representative of the situation at the whole Ebro level; the aim is to give an idea of the potential impact of salinisation per hectare with crops that are commonly grown in the central Ebro. To improve this estimate more information on water quality in the irrigation channels in the central Ebro according (data by channel and season) should be gathered.

5.4.4. Fisheries

Fisheries are an important activity in the Ebro basin (94 are registered with the CHE 48 ) and salinity of the water could have significant effects on fish species and stocks, but this depends on changes in both water quality and water levels (Figure 34 on ecosystem impacts shows some thresholds for fish). Although several parameters are checked to establish zones suitable for fisheries, they do not include any measure of salinity: in terms of water quantity a fishery needs 1,000 Hm3 of good quality water per year (CHE, 2005). The main fisheries are located in quiet upstream areas of rivers and very few are located in the central Ebro plain (1 in the region of Zaragoza on the Ebro) and few (about 5) are located downstream, almost in the delta (where the presence of salt could also be due to marine water). Consequently the direct economic impact of salinity on fisheries should be limited, but extra information and direct communication with producers would be required to confirm this conclusion.

47 For the loss estimation we assume that tomatoes correspond to one quarter of the vegetables 48 GIS data available at www.chebro.es

78

5.4.5. Industry and public equipment

Public equipment and infrastructure No information on observed damage to public infrastructure caused by salinity had been found within the Ebro basin in a literature and Internet review, but the effects of salinity on metal corrosion and the degradation of cement and roads were widely cited. Consequently it is probable that salinity problems have not reached the required level to cause this type of damage in the Ebro basin. Nevertheless two types of cost may appear in the future: (i) additional repair and maintenance costs of infrastructure and equipment, (ii) costs associated with the shortened expected lifespan of infrastructure and equipment (roads, vehicles, etc.). In the central Ebro - where salinisation is most significant - roads could be affected. This is most likely to affect Zaragoza and towns and cities downstream of this area.

To illustrate these impacts, some data 49 have been found for Australia, where the salinisation problem already affects 80 towns. The current cost of damage to infrastructure could be as much as Australian 60 millions Euros a year. For example a town like Wagga Wagga could bear a cost of Australian 300 000 Euros to cover the corrosion and degradation of roads, footpaths, parks, sewage pipes and housing by saline seepage.

Industry

Although no reported impacts have been found in the Ebro basin within the literature and Internet review, corrosion and degradation of equipment would also affect industry, whose yearly water demand is 470 Hm 3 (CHE 2005). Industries in the Ebro basin generate a yearly added value of 15.8 billion €1995 for 2002(CHE 2005).

Another specific impact of highly saline water is the need for some industries to treat the water (whether from groundwater or from public network) due to the need for high quality water in their production processes their water quality requirements are high.

Industry type Requirements (maximum salt in mg/L) Effects

All > 100 mg/L sulphates / chlorides corrosion of metals Boiling / warming water 50-3000 mg/L according pressure systems 50 mg/L sodium foaming Agro-food industry 50-100 mg/L dissolved salts Dairy industry 60 mg/L sulphates Sugar industry 200 mg/L sulphates Brewery 100 -500 mg/L dissolved salts 100 mg/L sodium sulphate Textile industry 100mg/L sulphates Paper - thin paper : 200 - Kraft paper 300 (bleached) 500 (none bleached) - sulphate pastes : 250

Figure 41. Requirements on water quality for several industries (Bremond 1979)

Faced with high salinity levels industries have two choices: (i) turn to another water resource if possible, or (ii) implement water treatment processes. Generally solutions for industry in

49 www.abc.net.au/science/slab/salinity/default.htm

79

order to diminish salt and conductivity are (i) for chlorides: demineralization with ionic exchanges, distillation, reverse osmosis, electro dialyses; (ii) for sulphates: softening, in some workshops sulphur acid can be replace with chlorhydric acid (which can be regenerated); (iii) for sodium: demineralization.

The area surrounding Zaragoza is one of the two main industrial areas of the basin, an area where surface and groundwater resources are affected by significant salinisation. A study of the possibility to use groundwater for the industrial and the drinking water supply states that water would not be adequate for these uses partly due to salinisation levels in water 50 . The important hydropower industry is unlikely to be severely affected because it is largely located upstream of the basin are, where water quality (in relation to salts) is good, although there are some important hydropower plants are located downstream of Zaragoza.

Quantitative effects of salinisation on Ebro basin industry have not been evaluated. In order to do so, information on the location of water users and quantities used by each type of industry would be required, as well as information about the strategies (and their cost) chosen by different industries to reduce the salinity of their intake water to a suitable level. This calculation would be of value because a lot of industries are located in one of the more affected regions of the basin and aggregated costs are likely to be important.

5.4.6. Synthesis of the impacts of salinisation Data from Australia on the cost of salinisation to society 51 show that there is a real need to predict impacts on the Ebro basin and plan for the future. Studies in different catchments quantified the annual costs of rising water tables and salinity at Australian 0,6 millions Euros per 5,000 ha of visibly affected land. This cost includes additional repair and maintenance of infrastructure and equipment, the costs of undertaking protective works or actions, costs associated with the shortened expected lifespan of infrastructure and reductions in revenue because of reduced capacity, and charges for extra infrastructure or services. Ghassemi et al. (1995) have commented on the loss of agricultural production due to salinisation in Australia. It would represent about 40 millions Euros annually. To this figure must be added another 70 millions Euros arising from the degradation of infrastructure and lost water resource.

5.5. EXTERNAL DRIVERS AND TENDENCIES : A FIRST OVERVIEW

External drivers that could have an impact on water salinity are those that could have an impact on sectors or systems identified as internal drivers and pressures. Different types of drivers must be distinguished, including: (i) natural conditions; (ii) economic and social conditions and (iii) environmental and agricultural policy.

5.5.1. Natural conditions

As salinity directly depends on the hydrological cycle, climate change is likely to have an impact on the level of salinity in surface waters and groundwaters. Above all evaporation plays a very important role: the more water is evaporated the more salts are concentrated in

50 IGME, CONTENIDO EN METALES PESADOS DE LAS AGUAS SUBTERRÁNEAS EN LA CIUDAD DE ZARAGOZA. Available at www.igme.es (spain geological survey)

51 www.abc.net.au/science/slab/salinity/default.htm

80

the water and precipitated in the soil. Exceedingly high air temperatures may cause a reduced salt tolerance (Tanji 2002).

5.5.2. Economic conditions - environmental and agricultural policies

Water demand and irrigation efficiency

Increase in water demand will have an impact on both water flows and water resources: these are directly linked to final salinity in water as main water uptakes do not “withdraw” salt and therefore salts are concentrated in the remaining water (reducing any dilution effect).

Population growth, increased industrial activity, leisure demand (golf courses for instance) and water prices have an impact on drinking water demand. Demand is forecast to increase from 319 Hm3 (demand stated in the current basin management plan) to 355 hm 3 by 2015 representing an increase of 11% (CHE, 2005). Some new drinking water treatment plants are planned (desalinization plants in la Tordera for instance). Furthermore the objective of a treatment of 90% of the urban discharges that is fixed in the basin management plan should have a positive impact on surface water, also likely on salinity issues.

Direct emissions of salts into the Ebro are another factor likely to be phased out of industrial practices in the relevant industries (mines, heating, chemicals, textile, agro food and paper). General economic policies on industry may have an indirect effect (for instance dispersion of textile or chemical industries would suppress contamination pressure for these industries).

In relation to agriculture, the Irrigation Plan (“Plan National de Regadio”) was launched in 2002 and aims to restructure, modernize and consolidate agriculture in Spain in order to strengthen agricultural economy and society, reduce the problem of water scarcity and the resultant negative environmental impacts. This program will cost more than €5 billion and would reduce, at national level, water demand by 9%, in part by considerably improving the efficiency of irrigation (Barbero 2005). In addition the 2003 Common Agricultural Policy (CAP) reform may exert impacts on crop choices and farming practices. For instance irrigation will no longer be subsidized compared to non irrigated crops, which could have an impact on choices of agricultural practice. Nevertheless, across large areas of the Ebro basin, agriculture is not possible without irrigation; therefore any impacts of CAP reform concerning irrigation might be limited.

In parallel, the National Hydrological Plan (PHN) aims to improve water management and water benefits through water transfers and dam construction in order to (among other aims) extend irrigated areas. Additional irrigation areas may exacerbate the salinisation problem, whereas modernization and increasing the efficiency of irrigation agriculture areas would certainly reduce exported salt loads per hectare. Dams could also have an impact on evaporation and would consequently affect water salinity.

Incentives to reduce direct impacts

Factors influencing industry and agriculture to reduce their emissions include regulatory and economical incentives; voluntary schemes are rare. Regulations include European directives or other national environmental policies in the field of industry or agriculture. Economic constraints include taxes (on discharges, fertilizer uses...) or fines corresponding to the level of impact of the water user. For those industries for which salts are a raw material, market prices of chlorides and sulphates must have an influence on the choices of recycling and the level of use. This is particularly true for extractive industries, namely salt and potash mines.

These factors of change or drivers would have impacts on water quality that could be modelled as part of the State section of the DPSIR scheme. A literature review has identified several trends. During previously measured periods (1981-1986 and 1994-2002) conductivity

81

has risen by 17.6%. Moreover, the Spanish government expects that salinity will increase by 20-50%, which will result in an average salinity of 1,600 S/cm. Taking into account the high seasonal variations, this could lead to conductivity levels of above 2,000 S/cm in autumn (WWF 2003). Other authors suggest an annual increase of 10-15mg/L TDS in the Ebro (Quilez, 1993).

5.6. RESPONSES-MEASURES

The last section of the DPSIR scheme is the responses that could be taken by users or regulators in order to react to the impacts caused by the state of the water and lessen those impacts. Responses can be of various types (see chapter 1).

- Preventive responses that act on pressures and have a subsequent effect on state and impacts;

- Curative responses that act directly on the state;

- Adaptive responses that are taken by users in order to avoid impacts of the state

Furthermore, both salinity focused measures and general measures should be distinguished because they have different objectives. Examples for the salinity problem in the Ebro basin are given below:

Preventive responses

Acting on pressures means a change in production and organization of one or several sectors responsible for salinity. In this case study this could concern industrial, agricultural and infrastructure (deicing) sectors. Focused measures aimed at reducing point source pollution or salt waste disposal could be applied to industries, mines and deicing. Such measures could include regulation (such as a code of practice), quotas or taxes.

Agricultural efforts could concern non focused measures to improve water and land management, mainly in order to reduce water infiltration 52 :

- Optimizing cropping patterns after having stated land vulnerability: minimizing crop impact, for instance putting the less harmful crops on saline vulnerable soils (alfalfa, permanent crops would absorb more water because they have a longer growth period and absorb deeper water);

- Maximizing permanent soil coverage;

- Installing drainage systems in order to limit water stagnation and evaporation which leads to salt concentrations;

- Adopting reduced ploughting land management to reduce deep soil work;

- Favoring organic material accumulation (the more organic matter the more water can be stored in soils);

52 http://www.futura-sciences.com/comprendre/d/dossier645-7.php

82

- Modernization of the irrigation management system in order to improve irrigation efficiency;

- Adjusting water supply to the precise needs of the crops;

- Limitation of percolation of water and return flows to groundwaters outside the cropped area.

Concerning other sectors:

- Optimizing land occupation to land vulnerability (for instance avoiding putting wastes over vulnerable groundwaters or minimizing infiltration through constructions);

- Recycling / treatment of rich salt waste waters of industries;

- Minimizing the use of salt on roads in winter, finding alternative, less harmful, solutions for deicing.

Curative responses

In the case of the diffuse saline pollution, this type of response does not seem to be relevant. Some tests on the use of soil reclamation plants that resist salinity, sodicity (plants used for grazing) were done, without being successful at such a basin level. It is not economically realistic to treat soils and water in the environment unless they were point-sources pollution such as those due to mine slag heaps (phosphate or salt extraction).

Adaptive responses

These responses could be implemented by the water user or a group of users who use the same resource. No significant change in the water state is notable. Some adaptive responses have been proposed by the drinking water or the industrial sector; they do not seem to be cost–efficient or feasible for the agriculture in the Ebro basin (Arrojo 2002) :

• Turning to another water resource,

• Treating water in order to reach quality requirements of industrial processes or imposed quality norms such as electrodialisis, reverse osmosis and nanofiltration: residues can then be evaporated under high pressure or infiltrated into deep aquifers.

It should be noted that the main (preventive) responses concern the agricultural sector, which seems to exert the most pressure on water in relation to salinity. These measures would also have an effect on water consumption (which is one of the main water issues in the Ebro basin). This would mean that the benefits of these measures would not only be for those affected by salinisation (including ecosystems), but also for users affected by quantity issues, although in many cases these are the same users.

5.7. CONCLUSION

This study aimed to describe the DPSIR scheme for the water salinisation problem in the Ebro basin. Elements of the scheme are gathered in the following figure.

83

Figure 42. Conceptual model for the Ebro case study

This description showed that the pollution is not only a point source pollution problem (industry) but mainly a diffuse pollution problem (mainly through agriculture, but also through industry, mines and the deicing of roads). Diffuse pollution is the concern of many different users. The main water bodies and users affected (surface and groundwater resources) are in the central Ebro basin, where nearly all pressures are combined. As this study was primarily based on a literature and Internet review, results on likely pressures and impacts must be treated with caution, but they show the types of pressures and their impacts on conditions of existence and ways users may react. Users exerting pressure and affected by impacts are often the same, but they are not necessarily in the same areas: farmers are both the source and receptors of the salt Pressure. Industries that emit salt are often those that have high requirements for water quality with regard to salt and therefore produce salt in their outputs after water treatment. The high number of actors involved and the fact that the pollution is largely due to natural sources makes economic analysis even more difficult.

Another objective was to explore the economic impact of the salinisation problem. A general quantification for the Ebro basin would require a much larger work than this study, but some figures were calculated or derived from literature. From this information it is possible to state that the main economic impacts seem to be for the agricultural sector (both those present on saline soil and those using irrigation water affected by irrigation return flows in the central valley corridor). Although no detailed study has been made, it is likely that industries bear a considerable cost of salinisation whether for their high quality requirements or because they are affected by corrosion. Roads and public infrastructure are also likely to be affected. The drinking water sector is not affected today (unless asking for derogation for temporary exceedences), because water quality is still acceptable, but future treatment costs or even costs due to a change of water resource (pipelines, wells..) might appear in the Ebro basin. The impact of land salinisation due to intensive irrigation on saline soils and subsequent

84

desertion of the land has not be calculated here but it is another likely future cost of water salinity combined with human uses which could be tremendous.

The short overview of the likely impacts of global change on salinisation showed that the salinisation problem may increase in the future, implying cost for users, even for those that don’t bear any direct cost of salinisation today (drinking water and industrial sectors). The future case study work could aim at evaluating these future costs by (i) constructing a prospective framework of salinisation drivers and (ii) identifying future direct costs and adaptive strategies for affected users. To seriously assess the costs of the future impact of salinisation, biophysical and hydrological modeling would be required or at least expert advice in order to make a link between pressures and state (and then impact). If point pollution sources are quite easy to extrapolate to impacts for surface waters (dilution), diffuse pollution phenomena are more complex (such as the impact of the dilution of salts in soil on available water quantities) and involve an important number of parameters. One shortcut would be to gather available studies of the future state of water in order to evaluate future costs. This approach would not enable analysis of “responses and measures” impacts and benefits as would be required for a cost-benefit analysis of programs or measures.

REFERENCES

Abdul-Kareem Al-Sofi, M. (2001). "Seawater desalination -- SWCC experience and vision." Desalination 135(1-3): 121-139.

Alberto, F., Aragues, R., Quilez, D. (1986). "Balance de sales en la cuenca del Ebro." Sistema integrado del Ebro: Estudio interdisciplinar: 279-291.

Albiac, J., Martinez,Y.,Tapia,J. (2005). Water quantity and quality issues in Mediterranean agriculture. OECD Workshop on Agriculture and Water: Sustainability, Markets and Policies, Australia.

Albisu, L. M., Gil, JM., Aragues, R. (1988). "Impacto economico de agua salina en la agricultura de la cuenca del Gallego." Communicaciones INIA, Serie economia 25.

Arrojo, P. (2002). Analisis del documento de Evaluacion Ambiental Estratégica del PHN presentado por el Gobierno Español a la Comision Europea.

Barbero, A. (2005). The Spanish National Irrigation Plan. Agriculture and water : sustainability, markets and policies, Australia.

Barberon, F., V. Baroghel-Bouny, et al. (2005). "Interactions between chloride and cement-paste materials." Magnetic Resonance Imaging

Proceedings of the Seventh International Conference on Recent Advances in MR Applications to Porous Media 23(2): 267-272.

Bremond, R., Perrodon,C. (1979). Les paramètres de la qualité des eaux, Ministère de l'environnement et du cadre de vie.

Causapé, J. (2003). Revision bibiliografica sobre la eficiencia del riego e impacto medioambiental en los recursos hidricos de zonas regables de la cuenca del Ebro, CHE- Oficina de planificacion hidrologica: 61.

Causapé, J., L. Auqué, et al. (2004). "Irrigation effects on the salinity of the Arba and Riguel Rivers (Spain): present diagnosis and expected evolution using geochemical models." Environmental Geology 45(5): 703-715.

Causapé, J. and I. Claveria (2006). "Drought as an agri-environmental determinant of irrigation land: the case of Bardenas (Spain)." Environmental Geology: 1-8.

85

Causape, J., D. Quilez, et al. (2004). "Assessment of irrigation and environmental quality at the hydrological basin level: II. Salt and nitrate loads in irrigation return flows." Agricultural Water Management 70(3): 211-228.

Chapman, A. S. & Bardos, P. (2005). Case study on the Ebro River Basin (characterisation). Deliverable I1.1f of the Aquaterra project., R3 Environmental Technology, Department of Plant Science, University of Reading, UK.

CHE (2005). Analisis economico del uso de agua, Ministerio de Medio Ambiente.

CHE (2005). Control del estado de las masas de agua superficiales (CEMAS). Informe de situacion.Año 2005.

CHE, C. H. D. E. (2005). Informe de situacion. CEMAS.

Cuartero, J. and R. Fernandez-Munoz (1998). "Tomato and salinity." Scientia Horticulturae 78(1-4): 83-125.

Darmendrail, D., Cerdan, O., Gobin, A., Bouzit, M., Blanchard, F., Siéguele,B. (2004). Assessing the Economic Impacts of Soil Degradation. Volume 2: Case Studies and Database Research, Consolidated Version, March 2004, Study Contract ENV.B.1/ETU/2003/0024.

Global Water Intelligence (2006). Market profile : desalinisation market 2007 preview. 7.

Institute for European Environmental Policy (IEEP) (2000). The environmental impacts of irrigation in the European Union Commission. London.

Isidoro, D., Quílez, D. (1995.). Caracterización iónica de las aguas superficiales de la cuenca del Ebro. XIII Jornadas técnicas sobre riegos, Tenerife.

Kefford, B. J. (1999). "The effect of salinewater disposal : implications for monitoring programs and managment." Freshwater ecology.

Meybeck, M. (1979). "Concentration des eaux fluviales en élements majeurs et apports aux océans." Revue de géologie dynamique et géologie physique: 215-246.

Tanji, K. K. K., Neeltje C. (2002). Agricultural Drainage Water Management in Arid and Semi-Arid Areas. F. I. A. D. PAPER. Rome, FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS.

Williams, W. D. (2001). "Anthropogenic salinisation of inland waters." Hydrobiologia 466(1 - 3): 329- 337.

WWF, F. N. C. d. A. (2003). Water quality in the Ebro river- Summary.

Zekri, S. and L. M. Albisu (1993). "Economic impact of soil salinity in agriculture. A case study of Bardenas area, Spain." Agricultural Systems 41(3): 369-386.

86

6. The Krsko kotlina aquifer (Danube, Slovenia): nitrates and pesticide pollution in groundwater

For further information, please contact Pierre Strosser (Acteon)- [email protected]

6.1. INTRODUCTION - CONTEXT AND AIM OF THE STUDY

6.1.1. General context

Much attention has been given in recent years to the status and quality of surface water and groundwater resources in Slovenia in the context of the implementation of the WFD and the preparation of the Article 5 report submitted to the European Commission. Overall, the assessments developed for the characterisation report have investigated the main pressures and impacts on water resources as input to the assessment of the risk of failing the WFD environmental objectives (i.e. good water status for all waters).

With regards to groundwater, difficulties have been met for analysing karstic waters for which there is much uncertainty with regards to water per se (water flows are not unidirectional and they can change direction depending on the rainfall conditions – including changing the river basin in which they flow) and with regards to the source and fate of pollutants. The hydrological functioning of alluvial aquifers, at the contrary, are better understood. The assessments undertaken in preparation to the Article 5 report stress the importance of pollution in the major alluvial aquifers – mainly nutrients and pesticides resulting from inadequate agricultural practices and intensive agriculture in wider plain areas of the country.

The Krsko kotlina aquifer, selected as case study for Integrator, is representative of the situation of most alluvial aquifers in Slovenia. As it will be presented below in more details, its current water quality is not yet below drinking water quality standards as it happens in some other major alluvial aquifers. But it is still deteriorating.

The main reason behind the selection of the Krsko kotlina aquifer as case study was the possibility to access information and study results of other on-going projects and research activities relevant to the understanding of the socio-economic dimension of this system. Indeed, the Krsko Kotlina aquifer was selected as case study by the project entitled Technical Assistance for the preparation of the Krka river basin management plan located in the Krka sub-basin co-financed by the European Union (PHARE funding) 53 to test economic methods relevant to the implementation of the WFD. Also, specific activities for the valuation of environmental costs and benefits have taken place in this area, as part of the Krka Pilot project and also with input from the EU-funded BRIDGE research project that aims at proposing a sound methodology for the establishment of threshold values for pollutants in groundwater for the forthcoming EU groundwater directive 54 . Thus, the case study presented below builds directly on the different reports of the Krka Pilot project in particular (see the web site of the project for the full version of these reports).

53 The main aim of this project is to test methods and tools for supporting the implementation of the EU WFD and the development of river basin management plans in Slovenia. It has been implemented by a consortium led by Hidroinzeniring d.o.o. (Slovenia), with ECORYS Nederland (The Netherlands) and IEI d.o.o. (Slovenia) as members of the consortium. For more information on the Krka Pilot Project, see http://www.hidroinzeniring.si/Krka 54 BRIDGE research project web site: http://nfp-at.eionet.eu.int:80/Members/irc/eionet-circle/bridge/library?l=/deliverables

87

The case study area does not have direct links with other Aquaterra sub-projects and activities. However, tools developed for modelling the fate of nutrients and for understanding nitrate and pesticide pollution in groundwater, developed in other case study areas of Aquaterra are considered to be very relevant to the Krsko kotlina aquifer and to the understanding of the fate of pollutants in this area 55 .

6.1.2. The Krsko kotlina aquifer – general characteristics

The Krsko kotlina aquifer covers an area of around 97 km 2 (see Figure 43). It is composed of 20 meters of quaternary sediments (the most important layer from a water point of view and highly permeable), of Pliocene sediments (between 0 and 600 meters of thickness) and of Miocene sediments with very low permeability. Rainfall in the area ranges from 900 to 1200 mm per year on average. Evapo-transpiration is estimated at 700 mm per year. The boundaries of the groundwater body do not coincide with administrative or surface water catchment boundaries. Indeed, the groundwater body area is shared between two municipalities. It is also shared between the catchment area of the Sava main river and the catchment area of its tributary the Krka River.

The aquifer is mainly recharged from precipitation, and to a much lower extent from the Sava river (average river flow of 290 m 3/s), the Krka river (average river flow of 55 m 3/s) and from small creeks. The groundwater body might also be connected to wetlands along the Krka river and to the most downstream part of the Sava river itself – the aquifer contributing itself to river flows. And the need to protect wetlands might impose specific constraints (stricter objectives) for the management of the groundwater body. However, such relationships are highly uncertain and are not considered in the present case study.

Slovenia & its regions

Figure 43. Hydrological boundaries of the Krsko kotlina aquifer

55 If applied, such tools would however need to be calibrated and validated for local conditions.

88

The area hosts protected areas designated because of the abstraction of water intended for human consumption. Water protection zones are defined for the protection of the two main abstraction wells of Brege and Drnovo (see more information below on these wells).

6.1.3. Overall objective of the case study

Similar to other case studies of Integrator presented in this report, the main aims of the Krsko Kotlina case study are:

(i) To apply the DPSIR framework to the case study and develop a simplified representation of the system under studies that specify the different socio- economic variables and relationships that need to be investigated (i) for understanding the socio-economic impacts of global changes and (ii) for assessing the economic impact of possible responses;

(ii) For the main socio-economic sub-systems of this simplified representation, to specify the components of socio-economic models that would need to be developed for understanding behaviours and links between global drivers, economic sectors and pressures;

(iii) To develop simplified models for the main socio-economic sub-systems;

(iv) To apply this simplified framework and models for identifying the likely environmental and economic impact of different responses and assessing the economic impacts of global changes;

The case study focuses on groundwater only and does not consider soils aspects (or sediment aspects that are not relevant to groundwater).

6.2. ANALYSING DPSI IN THE KRSKO AQUIFER

6.2.1. Main pressures & drivers

A series of pressures lead to pollution (nutrients, organic matter…) of the aquifer. These include: • Pollution from leakage of sewerage system (estimated at 25% of total wastewater produced by households and connected industry); • Diffuse pollution from dispersed settlements not connected to wastewater treatment plants and using ineffective cesspits or just letting wastewater flow into the natural environment • Pollution from inadequate fertiliser and pesticide applications/use in agriculture • Pollution from farm yards in terms of livestock manure that is not properly stored/that leaches to the groundwater aquifer • Pollution from landfills – legal landfills (few and large) and illegal (small and numerous) • Pollution from industrial polluting discharges • Roads

Pollution from the recharge of the Sava River and Krka River is considered to be minimal and can be neglected.

89

The following figure presents some of the basic characteristics of case study area and of the main sectors imposing pressures on water resources. Overall, the main pressure on the Krsko kotlina aquifer in terms of nutrient and pesticide surpluses originates from the agriculture sector – other sources of nutrient pollution being marginal.

Variable Unit Value Total area Km 2 97 Agriculture area % of total area 73.8 Urbanised area % of total area 8.6 Forest area % of total area 12.8 Other natural areas % of total area 4.8 Total population Inhabitants 6 363 Population density Inhabitants/km 2 66 Road density m/km 2 683 Industrial landfills Units 1 Communal landfills Units 2 Wastewater treatment plan discharges Units 11 Plants under the IPPC directive Units 5 Expected N- surplus from agriculture Kg/ha (average value) 57.8 Expected N-surplus from urbanisation Kg/ha (average value) 2.5 Expected N-surplus others Kg/ha (average value) 0.7

Figure 44. Key features of the Krsko kotlina aquifer

In terms of abstraction, there are two main pumping stations (Brege and Drnovo) abstracting groundwater from Krsko Kotlina for municipal water services. These two wells abstract together an average of 60 l/s – for a maximum capacity of 110 l/s.

Industry abstract water directly from the aquifer for technological processes, but total volumes are very small, in particular as compared to the water abstracted by irrigation of crops (mainly fruits and vegetables) through legal or illegal boreholes (see below). Within the municipality of Krško, several wells are used by the following industries:

• Abstraction by Vipap (Paper and Cellulose Industry) with water used only for the industrial process;

• Abstraction by the Krško Nuclear Power Plant with water used only for the cooling process;

• Abstraction by three different construction companies (IGM, Begrad and Cestno in Gradbeno podjetje) with but the water is only used for the process not for the drinking water.

Other industries or services such as Cerklje Airport or Ino Industry do not have self supply but are connected to the public water supply system. Vino Brežice has its own well, but this well is not abstracting water from the Krsko kotlina aquifer.

In the area of Municipality of Brežice, four wells are used by Čatež Spa, a thermal center of international reputation. Two of these wells are thermal wells abstracting water from depths of 564 and 532 m, respectively. Thus, they are not connected to the shallow layer of the aquifer that is under pressure from pollution. The two other wells are connected to this

90

shallow groundwater at a depth of 10 to 15 m. And they are used for supplying drinking water to the thermal center.

Agriculture also abstracts water for irrigation of crops (mainly fruits and vegetables). Many boreholes for agriculture are not yet under control or are also indeed illegal. The main two wells for irrigation are the Ecrosad well in the municipality of Krško and the Cvetje Čatež well in the area of Municipality of Brežice. Wells are used by larger producers of vegetables such as tomato, gherkin, paprika, lettuce and producers of fruit like strawberries and apples. For irrigation, farmers also abstract water directly from the Sava River, the Krka River (in the area of Brod, Veliko in Malo Mraševo, Podbo čje, Malence and Kostanjevica) and also from gravel pits. In some areas, farmers have also their own abstractions which are not legally registered like in settlements. One irrigation system of around 260 ha named Kalce-Naklo has been developed in the municipality of Krško. In the municipality of Brežice, around 40 ha are irrigated.

6.2.2. State 56

As a result of the pressures described above and of nutrient leaching to the aquifer, nitrates concentrations are just below the starting point for trend reversal (i.e. 37,5 mg/l or 75% of the threshold value for drinking water quality of 50 mg/l). However, the last few years have seen a continuing increase in nitrate concentrations in groundwater that are getting close to threshold values (see Figure 45). This trend is clearly in contradiction with the non- deterioration clause promoted by the WFD.

VTPodV KRŠKA KOTLINA: Nitrati

70.00

60.00

50.00

40.00

30.00 nitrati (mg/l)

20.00

10.00

0.00 1997 1998 1999 2000 2001 2002 2003 2004 2005

Figure 45. Past trends in nirate concentrations in the Krsko kotlina aquifer (1998-2004)

Monitoring data highlights that pollution from other pollutants (e.g. priority substances, heavy metals) is not considered problematic. Concentrations for most pesticides are below threshold values on average (0.1 µg/l for individual pesticides, 0.5 µg/l for the sum of all active ingredients). But pesticides are found in all monitoring points and concentrations of some pesticides (e.g. desetilatrazine) might exceed quality standards at occasions. The concentration of atrazin is decreasing because of the recent ban in using this pesticide (see

Figure 47 and Figure 52). However, the concentration of other pesticides such as desetilatrazin or symazine is still increasing .

Average Critical parameter 2003 2004 Trend concentration Atrazin 0,023 0,026 0,024 Decreasing

56 Note: in the WFD jargon, “State” is combined into “impacts” in the context of the “pressures & impacts analysis” required under Article 5 of the Directive – which might leave some confusion when looking at the relevance of the DPSIR framework for the WFD.

91

Desetilatrazin 0,057 0,084 0,070 Increasing

Figure 46. Yearly concentrations for atrazin and desetilatrazin in Krsko kotlina (2003-2004)

VTPodV KRŠKA KOTLINA: Atrazin Kemijski status KRŠKO POLJE 0.350 0,09 0.300 0,08 0,07 0.250 0,06 0.200 0,05 0.150 0,04

atrazin (micg/l) atrazin 0,03 0.100 desetilatrazin (micg/l) 0,02

0.050 0,01

0.000 0,00 1997 1998 1999 2000 2001 2002 2003 2004 2005 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005

Kemijski status KRŠKO POLJE VTPodV KRŠKA KOTLINA: Skupni pesticidi

1.00 0,10 0,09 0.90 0,08 0.80 0,07 0.70 0,06 0.60 0,05 0.50 0,04 0.40 simazin (micg/l) pesticidi (micg/l) 0,03 0.30

0,02 0.20 0,01 0.10 0,00 0.00 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 1997 1998 1999 2000 2001 2002 2003 2004 2005

Figure 47. Trends in concentrations of selected pesticides in Krsko kotlina (1997-2004)

Overall, because of (i) the increasing trends in nitrates and pesticides concentrations and (ii) the expected average nitrate concentration at the equilibrium of 60 mg/l (thus significantly above the drinking water threshold of 50 mg/l), the groundwater body of Krsko Kotlina has been considered as being at risk in the context of the assessment made by the Geological Survey of the Republic of Slovenia for the preparation of the Article 5 report sent to the EC.

The comparison between recharge/potential groundwater resources and abstraction shows that abstraction is marginal as compared to the recharge of the aquifer. Abstracted groundwater has been estimated at 10% of total recharge stressing that over-abstraction is clearly not problematic for the Krsko kotlina aquifer.

6.2.3. A preliminary review of today’s impacts: water uses affected by today’s groundwater pollution

Today, with nitrate pollution below standard and pesticides only present at some points, there is not yet any impact on existing water uses. Water can still be used for drinking purposes and for industrial processes of the few industries abstracting groundwater in the Krsko kotlina aquifer. And the pollution levels recorded do not pose problems for agriculture water use.

The Brege and Drnovo wells are protected in line with the Decree on the protection of groundwater on protected areas of pumping system of Krško Water Supply (Skup. Dol. List, No 12/85), while other wells in the area are protected in line with the Decree on protected of water wells on the area of Municipality of Krško (O.J. of RS, No. 64/02, 90/02).

92

Based on expert’s opinion 57 , additional water quality measurements for atrazine and his metabolite desetilatrazine were suggested for the Drnovo and Brege abstraction wells and in user’s pipes. Indeed, existing monitoring data show increasing problems with desetilatrazine at the Drnovo abstraction well, with threshold values for this compound (0,10 µg/l) being exceeded several times and average concentration reaching 0,194 µg/l. Average value of desetilatrazine in Brege abstraction was lower at 0,098 µg/l – but clearly not far from the threshold value. Although monitored and recognised, these water quality problems have not yet led to specific investments by water suppliers.

6.2.4. In summary

The Krsko kotlina aquifer is currently under pressures from different sectors in terms of pollution. This results in groundwater pollution with the main sources of pollution being: (i) leakages from sewerage systems, (ii) inadequate sewage for dispersed settlements and malfunctioning sceptic tanks of individual households, (iii) leakages from landfills, (iv) inadequate management of farm yard manure, and (v) high use of pesticides and fertilisers in agriculture – this last pressure being predominant in the area. Overall:

• Nitrate concentrations in the aquifer are currently increasing.

• Pesticides can be found in most parts of the aquifer. Pesticides concentrations remain low on average so groundwater is still drinkable. But concentrations of some pesticides have been increasing recently. And current concentrations are at some occasions above threshold values in particular for the Drnovo abstraction well.

It is important to stress that some of the pollution of the aquifer might be transferred to nature protected areas that are hosting highly valuable birds, fishes and ecosystems and that could be threatened. However, there is no information available for understanding how the quality of the aquifer might put connected ecosystem at risk.

6.3. LOOKING AT TRENDS AND BASELINE

Trends in groundwater quality

Because of the dynamics of pollutants in the soil, and assuming that pressures remain as they are today, nitrate concentrations will continue to increase. If no action is taken, water from the Krsko aquifer might become non-drinkable in the medium term. Based on the current nitrate load, and accounting that 20% of the nitrates leached to the groundwater will be recycled through natural processes (bacteria), it is estimated that an equilibrium nitrate concentration of 60 mg/l will be reached in the longer-term if existing pressures are to remain.

Main drivers to polluting pressures

Drivers to polluting sectors

• Agriculture – expected increase in fertiliser use (driven by CAP prices and the still adaptation of Slovenian agriculture to the CAP system – fertiliser prices considered as constant) and intensification, but some agri-environment measures implemented

57 Expert opinion of the Institute for Health protection of the Republic of Slovenia (No. 310-522/1-92/04, dated on 14.01.2005)

93

that will compensate for the increased intensity. Thus, it is assumed that the same pressure will from agriculture.

• Municipal pollution – some improvements might be expected because of the implementation of the Urban Waste Water Treatment Directive. However, because of small settlements in the area, not really having impact in nutrient leaching to the aquifer

Main drivers to water abstraction and water uses

Although water abstraction is not a pressure and over-abstraction not an issue for the Krsko kotlina aquifer, trends in water abstraction and water use are investigated as they influence the magnitude of negative impacts increasing groundwater pollution will have.

Municipal water use from the Bregne and Drnovo wells will be mainly influenced by changes in population connected to these abstraction wells 58 . As all people from the area are already connected, these changes will be driven by population growth in the area. Figure 48 and Figure 49 present some parameters and trends for population and drinking water abstraction.

People connected to the abstraction wells of Drnovo and Brege 4.677 Estimated yearly population growth 0,68% Annual quantities of drinking water 387 933 m 3 Average water supplied per inhabitant 83 m 3

Figure 48. Estimated parameters for municipal water use(2005)

Year Parameter 2007 2008 2009 2010 2015 2020 2025 2030 People connected to the abstraction 4 677 4 709 4 741 4 773 4 938 5 108 5 284 5 466 wells of Drnovo and Brege Yearly quantities of drinking water abstracted by Drnovo and Brege 387 933 390 571 393 227 395 901 409 546 423 661 438 263 453 368 wells (in m 3)

Figure 49. Trends in people connected and drinking water abstraction for Drnovo and Brege wells (1997-2004)

As irrigation water use will not be influenced by increasing nutrient concentrations and pesticide concentrations, there is no need to assess future trends in irrigation water use. Also, irrigation will remain of very marginal importance in the area in the future. The same applies to industrial water use, apart for the Catez Spa. Indeed, depending on future trends in the number or visitors to the thermal center, drinking water use will evolve. The following

58 The assumption is made that income changes that are expected in the coming years will not affect average water use per inhabitant.

94

figures summarise some of the parameters considered for assessing trends in drinking water use for Catez Spa.

Average capacity of existing wells 7 l/s yearly estimated growth of visitors (and corresponding wter use) 1% Yearly quantities of drinking water (m 3) 220.752 Operational cost (SIT/m 3) 96

Figure 50. Estimated parameters for Catez Spa water use (2005)

Parameter 2007 2010 2015 2020 2025 2029 2030 Yearly quantities of drinking water 220 752 227 441 239 043 251 236 264 052 274 774 277 521 abstracted by Catez Spa (in m 3)

Figure 51. Trends in concentrations of selected pesticides in Krsko kotlina (1997-2004)

A review a land planning documents further stressed that no additional industry that might be affected by water quality problems was foreseen in the future. A new logistic centre only will be established near Leskovec pri Krškem – however its main activity will be store-housing and transport with no specific demand for drinking water expected from this new sector.

Because of the deteriorating groundwater quality, however, additional investments will be required to provide adequate drinking water to inhabitants. And drinking water treatment plants will have to be built to provide drinking water with properties as laid down in the Rules on drinking water (Official Journal of the Republic of Slovenia no. 19/2004). The main abstractors in the area that will need to mitigate drinking water quality problems are has affect, are the municipal abstraction from Drnovo and Brege wells and abstraction from the thermal center Catez Spa.

With regards to municipal abstraction, one alternative to the degradation of groundwater quality could be to find new abstractions for households or to connect households to other abstraction/networks that already are in place at reasonable distance. Because of the dispersed settlements and also the distances between them, the cost of such alternative would be very high and unlikely to be cost effective. Other alternatives include different technologies for the treatment of drinking water – with ultra-filtration and disinfection with chlorine being the two relevant options. Technological process with ultra-filtration has proved efficient for the elimination of suspended substances, the reduction of muddiness of water and for elimination of cysts or bacteria.

With regards to abstraction by Catez Spa, two wells are used for drinking water supply as indicated above. The alternatives for assuring good water quality (an issue of particular importance because of the need to eliminate risk for tourists and customers of the Spa center) are also new abstraction, the connection to existing public water supply system and possible treatment of drinkable water on existent abstraction. Considering the potential pollution that might occur (pesticides, nitrates, ammonia, bacteriological pollution and possibly smell and taste), Čatež Spa could select reverse osmosis water purification technology which appeared to be the most suitable system for that kind of needs of

95

treatment. The construction of two reverse osmosis devices with capacity of 15 l/s could be envisaged for covering the drinking water needs of Terme Čatež 59 .

6.4. POTENTIAL RESPONSES FOR RESTAURING GROUNDWATER QUALITY IN THE KRSKO AQUIFER

As described in the analysis of pressures and impacts, there is an increasing trend in nitrate concentration in groundwater for the Krško polje aquifer. As a result, nitrate concentrations will soon reach the 37,5 mg/l of nitrate for action specified in the WFD. With the current nitrate load to the aquifer, it is expected that nitrate concentration in groundwater will reach an equilibrium value of 60 mg/l by 2018 (thus significantly higher than the drinking water standard of 50 mg/l) if no action is taken.

Different levels of response can be envisaged. First, direct responses can be identified that deal with changes in farming practices and the development of infrastructure in the farm and municipal sectors. The main measures identified through discussions with local experts and stakeholders are presented below:

• Establishment of Water Protection Area I (or WPA I) – This measure applies to the first level of water protection areas (Water Protection Areas I or WPAI, defined with a transportation time of water to the abstraction well of less than 50 days) already defined in existing legislation for the abstraction wells of Brege and Drnovo. The measure requires the abandonment of mineral fertiliser and use of organic fertilisation restricted to compost. The costs of this measure represent the end of farm production in arable fields and the installation of (quasi-natural) meadows.

• Establishment of WPA II & III - In other water protection areas (second and third circles of the Brege and Drnovo abstraction wells), it is anticipated to reduce fertiliser input from 188 kg/ha to 170 kg/ha (in line with the requirements of Good Managament Practices). The main costs of the measure are costs of extension for raising awareness on balancing input of nutrients, protective means of rural economies, education for executing effective supervision, development of more efficient monitoring and obligatory preparation of fertilization plan.

• Good Farming Practices - In practice, measures of good farming practice consider arrangement of manure pits, decrease of input to minimal standard for light soil and vulnerable area, prohibition of fertilization during different time periods of the year, efficient control of carrying out fertilization and other measures. The main costs of this measure are costs for extension for raising awareness on balancing input of nutrients, protective means of rural economies, education for executing effective supervision, development of more efficient monitoring and obligatory preparation of fertilization plans.

• Winter green cover – This measure aims at growing winter crops to capture remaining nitrates and limit leaching during the winter. Costs include the direct costs of farm practices to put winter green cover in place (ploughing, sowing, etc), but potentially also indirect costs that might result from changes in cropping pattern and other farm practices that are required because of the installation of green cover.

59 These mitigation measures are responses that will be implemented by individual operators as part of the baseline to respond to the degradation of groundwater quality. Although they are of the same nature, they are not “policy responses” that will be part of the scenario case and will aim primarily at reducing pollution at source and limiting leaching to the aquifer.

96

• Buffer zones – Buffer zones are grass or forest areas installed along water courses (5 m wide on each side) for limiting runoff and nitrate leaching to mainly surface water. The cost of the measure is the related reduction in farm profit results from the abandonment of production for the areas under buffer zones. Although it is mainly implemented for surface water quality improvements, it can influence to a limited extend the quality of underground water.

• Ecological farming - Ecological farming implies that mineral fertilisers and chemical products are not used anymore and replaced by alternatives techniques and farm practices that are ecological. Today, there are around 5 to 10% of total farms involved in ecological farming in the area. It is expected that up to 15% of the farms could shift to ecological farming in the Krsko Kotlina area.

• Establishment of stricter WPA II & III for Brege – This measure is proposed only for the water protection areas II & III linked to the Brege abstraction well. With this measure, fertilization should be prohibited, leading to a reduction in nitrate surplus from approximately 110 kg/ha to less than 5 kg/ha. The cost of the measure represents the loss in farm production resulting from the drastic reduction in fertilisation.

• Establishment of stricter WPAII & III for Drnovo – This measure is similar to the previous measure but applies to the abstraction well of Drnovo. The cost of the measure represents the loss in farm production resulting from the drastic reduction in fertilisation. With this measure, fertilization should be prohibited, leading to a reduction in nitrate surplus from approximately 110 kg/ha to less than 5 kg/ha. The cost of the measure represents the loss in farm production resulting from the drastic reduction in fertilisation.

• Installation of septic tanks - Septic tanks have three treatment stages and they need regular sludge transportation to waste water treatment plants. It is estimated that this measure can be implemented for 25% of the population of the area, thus for 7 646 population equivalents (or PE).

• Construction of small wastewater treatment plans for small groups of individual houses (lower than 50 PE) - The measure foresees the installation of small waste water treatment plants with secondary treatment for individual houses or for a group of houses.

• Wastewater treatment plans for agglomerations between 50 and 2 000 PE. The measure foresees the construction of wastewater treatment plants for small settlements. It is assumed that the outflows from the waste water treatment plants will flow to surface waters and that there is around 1% of loss only that will go to groundwater.

• Renovation of existing sewage networks. Old networks might record high leakage rates that might have localised damaging impacts if close to abstraction points. The measure foresees the construction of wastewater treatment plants for small settlements. It is assumed that leakages to the aquifer will be reduced from around 10% to around 1%.

Second, more global responses or instruments relevant to the water sector can be envisaged.

• The application of economic instruments, expected to influence the decisions and behaviour of economic actors in a way that leads to reduction in nutrient leaching. Such economic instruments include the application, or increase of, a wastewater tax or wastewater charge in order to provide an incentive for industrial operators and

97

municipalities to improve the efficiency of their sewage and wastewater treatment system. Today, environmental taxes on wastewater exist for large dischargers. They are mainly relevant however to surface water as their level is based on the pollution discharged to the natural river system;

• Communication campaigns and extension for promoting for example environmentally friendly agricultural practices – such instruments are included in the description of technical measures as considered as key to their implementation

Such instruments are usually defined, decided and implemented at a higher (national) scale than more technical measures.

Third, responses can take place at higher levels but out of the water sector, e.g. regional or structural policies, and more importantly sector policies. With the importance of agriculture as main source of pollution in the Krsko kotlina aquifer, the main focus will to be on agriculture policy. For example, changes in the support regime of the Common Agriculture Policy (CAP), moving from price support to revenue support or implementing cross-compliance… are policy responses that are expected to influence farmers decisions and ultimately diffuse pollution. These changes will take place at the European scale. Along similar lines, quotas on fertiliser use or the imposition of a fertiliser/pesticides tax/charge are instruments to be considered when proposing options for reducing nutrient/pesticide pollution from agriculture.

6.5. SUMMARISING THE CONCEPTUAL MODEL FOR THE KRSKO AQUIFER

6.5.1. Application of the DPSIR framework to the Krsko aquifer

Based on the review of pressures, impacts and water uses in the Krsko area, we have applied to DPSIR framework and develop a simplified representation of the system that can be investigated that we will account for the study and define the boundaries in terms of sub- systems that are considered and their inter-relationships. In this sense it is a simplified representation of the reality limited to the hypothesis of the study: it is a way to simplify the reality.

Drivers are all driving forces that can have an impact on pressures, but also on impacts (an element that might not be sufficiently specified in the DPSIR framework but that influences the economics of different scenario). The drivers that can be considered in the context of the Krsko case study include:

• Climatic conditions: evaporation, precipitation, temperature…that might potentially influence leaching of nutrients to the aquifer.

• Economic drivers linked to the implementation of the CAP and to agricultural sector policy (prices of crops, prices of fertiliser and pesticides). These driving forces are expected to influence farmers’ decisions and their choices in terms of total area cultivated, types of crops, quantity of fertilisers/pesticides, agricultural practices applied… thus influencing in turn nutrient and pesticide surplus potentially leached to the aquifer;

• Population growth that influences abstraction for municipal water uses and thus the population potentially affected by groundwater pollution/benefiting from its improvement – but also the potential benefits derived from non-use values;

• Income levels influencing people’s willingness to pay for groundwater protection and thus the benefits that arise from this protection;

98

• Changes in the tourism sector (number of visitors, average stay of visitors) that influence the activities of the thermal sector and its water abstraction;

• Environmental policy – with regards to the agriculture sector, support to agri- environment measures and level of cross-compliance required in the CAP (integration between sector policy and environmental policy…), implementation of the Urban Wastewater Treatment Directive expected to reduce leakages to groundwater from sewage systems;

Pressures are the different types of pressures that influence the quality of the groundwater system. Pressures deal potentially with the main sources of nutrients and pollutants that are leached to the aquifer and affect its quality. In the context of the Krsko kotlina aquifer, these include:

• Pollution from agriculture: from inadequate crop fertilisation, livestock and manure management;

• Pollution from the municipal sector originates mainly from leaks from sewage systems and from inefficient sceptic tanks of individual households;

The State of the Krsko aquifer can be characterised by a series of indicators dealing with quantity and quality issues.

• With regards to quantity aspects, changes in groundwater levels is the main indicator that reflects the quantitative balance (or imbalance) of the aquifer. It derives from the comparison between groundwater levels at different periods of time. As over- abstraction is not an issue, no specific attention is given to this aspect;

• With regards to quality aspects, the main focus is on nitrate and pesticide pollution as demonstrated above. Thus, nitrate concentration and pesticide concentration – as compared to their threshold values – will be the two indicators selected for characterising the state of the Krsko kotlina aquifer.

State variables are limited to the concentrations of nutrients (nitrates) and pesticides in groundwater.

Impacts include potential impacts on human health through drinking groundwater polluted with pesticides and nitrates. Impacts also include costs imposed on water suppliers and industries because of too high concentrations of pollutants in the groundwater they abstract – and the need to comply with existing legislation dealing with the quality of drinking water. Finally, negative impacts on the groundwater ecology could be mentioned – although these are today not well known and very difficult to capture.

Responses include the following types of measures and instruments:

• Technical responses directly targeting sectors at the origin of pressures (agriculture, municipal) by chancing practices/processes that directly influence pressures or by putting measures in place that “capture” part of the pollution produced and thus limit leaching to the aquifer;

• Instruments applied to the water sector- economic instruments or soft measures for raising awareness for example;

• Changes in agricultural policy and access to agricultural inputs (quotas, prices).

Measures taken by water users for eliminating existing pollution from abstracted water (installation of denitrification plant, access to alternative source of water – surface water,

99

another aquifer or supply provided by another sector) can also be considered as responses to emerging groundwater pollution. However, these are individual responses included in the baseline. They are not considered as policy responses aimed at reducing environmental problems or their negative impacts.

6.5.2. Main assumptions made for defining the system and its components

The following section has presented a series of variables relevant to the different components of the DPSIR framework that will be considered in this groundwater case study. These variables and issues considered have been selected based on a series of assumptions for simplifying the case and focusing on main aspects. In particular:

• The interconnection between the groundwater aquifer and connected surface water bodies has been simplified. Pollution from the recharge of the Sava River and Krka River is considered as minimal and has been neglected.

• The need to protect wetlands might impose specific constraints (stricter objectives) for the management of the groundwater body. However, such relationships are highly uncertain and are not considered in the present case study.

• The impact of climatic conditions on farmers decisions in terms of crops and farm practices are not considered in our analysis. Thus, the impact of climate change is limited to its impact on hydrological parameters and processes (recharge to the aquifer and leaching of pollutants);

6.5.3. Presenting the overall system considered and its components

The conceptual model combining the different elements considered for DPSIR for the Krsko kotlina aquifer is presented in the following synthesis figure.

100

Climate change (rainfall)

Implementation of environmental policy

Population growth Agriculture policy Population growth Tourism development

Abstraction for Abstraction for drinking water Carez Spa Households Agriculture Dispersed settlements

Diffuse Leaching from Leaching from Leaching from pollution from Sewage sceptic tanks Sewage agriculture

Wetland Wetland Krsko kotlina aquifer

System under investigation

Krka River

Sava River

Figure 52. Conceptual model for the Slovenian case study

101

6.5.4. Key variables for the main economic sub-systems and decision making processes considered

For the main socio-economic and decision making processes, key input, characteristics and output variables relevant to the understanding of the relationship between these processes and the groundwater aquifer have been proposed. The following figures summarise these elements for the agriculture sector, municipal water services to households, disconnected households and thermal tourism.

Figure 53. Summary description of the agriculture sector for the Krsko kotlina aquifer case study

Figure 54. Summary description of the municipal (household) water service sector for the Krsko Kotlina aquifer case study

102

Figure 55. Summary description of the disconnected household sector for the Krsko Kotlina aquifer case study

Figure 56. Summary description of the thermal tourism sector for the Krsko Kotlina aquifer case study

6.6. CONCLUSION

The above framework can now be applied by developing a quantitative model focusing on the economic components of the system and illustrating how it can be applied to investigate different scenarios of change:

• Base case or no-action scenario – to estimate the economic impacts of such no-action scenarios on water uses potentially affected by the degradation of groundwater pollution;

• The economics of implementing direct technical measures for reducing nutrient leaching to the aquifer – looking in particular at the impact of different timings for the implementation of measures and at the balance between costs and benefits;

• The expected changes of farm practices with regards to nutrients and pesticides (and related pressures on the aquatic ecosystem) resulting from changes in global changes in the agriculture sector, e.g. changes in fertiliser prices, changes in CAP policy and financial support.

Some information and knowledge for building the quantitative integrated model economic model is already available and could be directly mobilised. In particular, the costs and potential impacts of individual technical measures have been collated. Also, different water treatment techniques that

103

might be considered if groundwater quality is degraded above existing water quality standards have been identified and their costs estimated. And interviews with relevant local experts have been made for complementing the understanding of the decisions taken by different abstractors and polluters. And a first assessment of the benefits that would arise from groundwater quality improvements has been made – building on a contingent valuation survey developed for the area – and this information and knowledge could be mobilised. Also, knowledge from the Aquaterra project (Aquaterra 2004) could be mobilised to develop simplified approaches to the bio-physical processes relevant to the movement and accumulation of nitrates and pesticides in the soil layers and groundwater aquifer.

The following table summarises for the different sub-systems considered the information and knowledge currently available from the Aquaterra project and from local studies and investigations (in particular from the Krka Pilot project) that can be mobilised for building a quantitative integrated model.

104

Figure 57. Estimated parameters for municipal water use(2005)

Sub-systems Information & knowledge base Aquaterra’s Non-Aquaterra What would be research & Comments Name Summary description knoweldge & research in Other relevant Aquaterra research required to transfer knowledge in case study area Aquaterra’s research? case study area Agriculture Agriculture sector specialised in cropping, No research of Aquaterra on this (farming) aimed at maximising farm profit under labour sub-system. Indeed, Aquaterra’s Information limited to and land constraints. Main input includes research starts with cropping pattern The availability of farm existing characteristics of fertiliser use, pesticide use and water use – No research of and can simulate the impact of models in other similar farming systems (available each specified in terms of quantity and price. Aquaterra in this different cropping pattern on Not relevant agricultural regions of at municipality/extension Output includes total crop production/farm case study area abstraction and pollution – but it Slovenia should be service level). However, no income, surplus in nitrates and pesticides does not investigate the variables assessed. farm model available. discharged to the environment and factors that influence cropping pattern. Water One municipal water supplier. Its objective is suppliers to deliver water services of adequate quality within given water price range. Poor quality Availability of existing groundwater influences choice of alternative No research of No study made, need to economic models for sources of water or investment in de-pollution Aquaterra in this build on local expertise of No research of Aquaterra in this field Not relevant this sector not expected technology – the existence of alternative case study area water suppliers (be it in Slovenia or sources today and their level of elsewhere) mobilisation/use, population growth and costs of alternatives impact on decisions to ensure good quality drinking water to customers Municipal Aimed at reducing leaching of effluents to the Study made as part of Krka sewage groundwater and surface water. Influence by Pilot project (Phase II) with efficiency of sewage collection and treatment, regards to proposed % of connected/non-connected households, investments in Availability of existing investments in wastewater treatment and sewage/treatment to No research of economic models for collection - influenced by total water use implement UWWTD, no Aquaterra in this No research of Aquaterra in this field Not relevant this sector not expected (mainly households), current environmental good information on case study area (be it in Slovenia or legislation (e.g. UWWTD) effectiveness of elsewhere) investments in reducing leaching to the groundwater (rough assumptions made) Thermal Thermal tourism activity abstracting water – sector maximising profit under constraints of service quality and consumer satisfaction. Use of groundwater mainly for drinking water Availability of existing of customers. Treatment technology choice No research of No study made, need to economic models for influenced by water quality level, availability of Aquaterra in this build on local expertise of No research of Aquaterra in this field Not relevant this sector not expected alternative technologies. Access to financial case study area water suppliers (be it in Slovenia or resources and water pricing not relevant to elsewhere) decisions. Influenced by future trends in tourism in Slovenia and in the area (that will change when Croatia access the EU) and compatitiveness as compared to other similar

105

Sub-systems Information & knowledge base Aquaterra’s Non-Aquaterra What would be research & Comments Name Summary description knoweldge & research in Other relevant Aquaterra research required to transfer knowledge in case study area Aquaterra’s research? case study area sites in former Yougoslavia Soil layer I Upper soil layer that receives nitrate surplus Biogeochem: (unsaturated) from economic activities. Bio-degradation BGC2: understanding and process taking place, part leaching to the quantification of soil functions saturated soil layer depending on soil BGC4: functioning of microbial characteristics, conductivity, rainfall… habitats influencing nitrates Involvement of Considered in the context decomposition in soil layer researchers from specific No research of of groundwater modelling BGC5: biodegradation of selected sub-projects for Aquaterra in this activities by the Geological pollutants including pesticides describing the main case study area Survey F1 – Bréville catchment assessment processes that are to be focusing on pesticides considered and The availability of F2: fluxes from soil to groundwater specifying their groundwater models for T1: tends in soils importance other aquifers of WP2: catchment scale modelling Application and Slovenia (5 main R1: Brévilles catchment calibration of WP2 aquifers facing similar Soil layer II Lower soil layer saturated, pollutants leaching Considered in the context WP2: catchment scale modelling models/Bréville nitrate/pesticide No research of (saturated) to the groundwater depending on soil of groundwater modelling F2: fluxes from soil to groundwater catchment models for the pollution) should be Aquaterra in this characteristics, conductivity, rainfall… activities by the Geological T2 – trends in groundwater Krsko kotlina aquifer. investigated. case study area Survey R1: Brévilles catchment Specific data Groundwater Krsko kotlina aquifer. Recharged by rainfall, Current work by the requirements for the F2: fluxes from groundwater to Sava and Krka river, supplying water to the Geological Survey of model to be assessed in surface water Sava river (downstream) and under different Slovenia to develop relation to data No research of WP2: catchment scale modelling pressures from economic operators hydrodynamic groundwater availability. Aquaterra in this T2 – trends in groundwater abstracting water. Pollutants reaching the model accounting for case study area R1: Brévilles catchment aquifer from above soil layers. Main spatial distribution of R3: nitrate and pesticide pollution in characteristics of the aquifer: conductivity, pollution sources one sub-catchment? water flows, thickness….

106

REFERENCES

Aquaterra. 2004. Description of Work. Annex I to the contract n° 505428 of the EU-funded research proj ect Aquaterra.

Bridge Project deliverables:

Krka Pilot Project. 2006a. Characterisation of the Krka River sub basin. Technical report of the Krka Pilot Project, Ljubljana.

Krka Pilot Project. 2006b. Selecting measures to improve water status in the Krka River sub-basin. Technical report of the Krka Pilot Project, Ljubljana.

Krka Pilot Project. 2006c. Application of environmental cost valuation methods in the Krka River sub-basin. Technical report of the Krka Pilot Project, Ljubljana.

Krka Pilot Project. 2006d. Cost benefit analysis for a groundwater case study in the Krka River sub-basin. Technical report of the Krka Pilot Project, Ljubljana.

107

7. Low flows in the Meuse river basin

For further information, please contact Erik Ansink (WUR) – [email protected]

7.1. INTRODUCTION – CONTEXT AND AIM OF THE STUDY

This chapter presents a conceptual model for analysing the problem of low flows in the Meuse river basin. This section describes the Meuse river basin and the characteristics of its river flow. The next section details the main water uses. Section three presents the conceptual model. Sections four and five provide information on the functioning of the sub-systems of the conceptual model and data availability for quantification of the conceptual model.

The rain-fed Meuse river is 950 km long and flows from the Langres Plateau in France to its mouth in the North Sea in the Netherlands, see Figure 58.

The basin covers 35,500 km 2 in six regions: France (26% of the total river basin area), the Walloon part of Belgium (36%), Luxembourg (1%), the Flanders part of Belgium (5%), Germany (11%), and the Netherlands (21%). Main cities along its course are Verdun, Sedan, Charleville-Mézières, Revin, Givet (France), Namur, Seraing, Liege (Belgium), Maastricht, Roermond, and Venlo (the Netherlands). Main tributaries are the Chiers, the Semois, the Lesse, the Sambre, the Ourthe, the Rur, the Schwalm, the Niers, the Dommel and the Mark (Bouzit et al. , 2005; IMC, 2005).

Figure 58. The Meuse river basin

The Meuse has a rainfall-evaporation regime (no water reservoirs in the form of glaciers) with an average discharge of 250 m3/s and total annual volume of 7.6 km 3. Because the Meuse is a rain-

108

fed river, peak flows can be as high as 3000 m 3/s in the early spring and minimum flows as low as 10 m 3/s in summertime (IWAC, 2001).

Mainly to facilitate navigation, a rather dense canal system has been implemented in the Meuse basin. The Albert canal connects the Meuse with the Scheldt river basin; the Maas-Waal canal connects the Meuse with the Rhine river basin. Other canals connect various sub-basins or run aside the Meuse river (a.o. the Juliana canal in the Netherlands). The river has been canalized over a total of 720 km for both navigation and hydro-power purposes.

Both for Belgium and the Netherlands, the Meuse is an important economic asset. Both countries use the water of the Meuse for various economic sectors as well as for abstraction of drinking water. A special interest of Belgium is the Meuse as a means of navigation to the Rhine and North Sea. A special interest of the Netherlands is flood protection.

These—sometimes—non-corresponding interests have lead to a history of negotiation and cooperation on both water quantity and quality issues in the Meuse river. A first agreement, signed in 1863 between Belgium and the Netherlands, was “to settle permanently and definitively the regime governing diversions of water from the Meuse for the feeding of navigation canals and irrigation channels” . As economic development in both countries increased, new and enlarged construction works and canals were constructed (a.o. the Juliana canal and Albert canal). This resulted in both countries accusing each other of breaching the 1863 treaty, culminating in a case before the Permanent Court of Justice in 1937, which did not bring a resolution. Only in 1994, the major Meuse countries (France, Belgium, and the Netherlands) signed the “Agreement on the protection of the Meuse”. This agreement covered both (i) equal sharing between Belgium and the Netherlands of the Meuse discharge during low water periods, and (ii) protection of water quality in the Meuse (Huisman et al. , 2000; IMC, 2005).

Floods in the Rhine and Meuse basin in e.g. 1993, 1995, 2003 (cf. De Wit et al. , 2001), as well as actions for the implementation of the Water Framework Directive, have given a new incentive for cooperation between the Meuse countries. Extreme low flows in the summer of 1976 and—more recently—1991, 1996 and 2003 caused damage to a range of economic sectors. Most notably in the Netherlands: navigation was hampered because of decreased channel depth; the continuity of power supply suffered from the high temperature of surface water; and the stability of dikes was threatened by decreased water levels (Ministerie van Verkeer en Waterstaat, 2004).

Clearly, the allocation of the Meuse water and the regulation of low flows are of importance, especially for the downstream Netherlands (cf. RIZA 2005a,b). Decisions in upstream regions affect the availability of water. In times of water scarcity, water use by various economic sectors has to be weighted against each other. In the next sections, these topics are analysed from an economic perspective. The area for which analysis of low flows is relevant is limited to the stretch north of Liege (Belgium) until Roermond (Netherlands), where a stretch of the Rur ends into the Meuse, including the canals. In the analysis we follow Raadgever (2004) who divided the Meuse in 18 branches: Meuse (M1-4), Juliana canal (Ju), Lateraal canal (La), Kanaal Wessem-Nederweert (We), Noordervaart (No), Wilhelmina canal (Wi), Zuid-Willemsvaart (Z1-4), Albert canal (A1-3), and Bocholt-Herentals canal (B1-2), indicated on Figure 59.

109

Figure 59. Relevant branches of the Meuse

7.2. OVERVIEW OF WATER USE

Water is being used by various economic sectors as an input to production processes and as a sink for (treated) wastewater. The following description of main economic sectors using water includes industry, agriculture, energy, and drinking water. Of course, there are more uses for water. Nature requires a minimum flow to sustain ecological processes and fish migration. Recreation requires a minimum flow for various water-related activities. On top of these minimum requirements for the Meuse flow, the pressure of economic sectors has increased over the last decades, with intensification of agriculture and economic growth.

7.2.1. Industry

Meuse water is being used by industries for processing, cooling and as a sink for wastewater. Largest industrial sectors in the Meuse basin are the textile, metal, materials, food, and chemical industries. The main companies responsible for water abstraction are DSM and Sappi (the Netherlands). Both companies also dump residual water into the river (return flows), decreasing their net abstractions. In case of water shortage, industries may be required to reduce their water abstractions or to decrease the temperature of their residual flows. Industrial water use accounts for 8% of total water use in the area, see table 2.

110

7.2.2. Agriculture

Irrigation is the main use of water abstraction by the agricultural sector. Residual nutrients and pesticides also enter the river system because of leaching. More intensive farming occurs in the Netherlands part of the area. Farms are mainly specialized in grazing livestock and in specialized crops (Bouzit et al. , 2005). In case of water shortage, sprinkling may be regionally limited or prohibited. Agricultural water use accounts for 50% of total water use in the area, see Figure 61.

7.2.3. Energy

The energy sector has two distinct uses of the Meuse water. First, conventional power plants (two in the Netherlands, two in Belgium) use the water as cooling water, where the amount of cooling water needed depends on water temperature and production capacity. At low flow levels, water has to be pumped into towers in order to cool effectively. In addition, energy production becomes less efficient at higher water temperatures, and residual flows have a maximum allowed temperature. Second, hydro-power plants need a minimum flow to sustain production-levels. Water use for the energy sector accounts for 6% of total water use in the area, see Figure 61.

7.2.4. Navigation

The Meuse is an important navigation route in Europe. Locks and weirs have been constructed along large parts of the river, and a number of canals have been constructed to connect sub- basins and facilitate navigation. Navigation needs a minimum river flow in the navigable river channel, as well as water to compensate for losses and abstraction at locks. When these requirements are not met, ships need to reduce their load such that their depth decreases, and waiting time at locks increases. Obviously, such a situation will increase marginal transportation costs.

7.2.5. Drinking water

Drinking water is being abstracted from the Meuse directly, both in the Netherlands and Belgium. Also, groundwater abstraction for drinking water in the Meuse area affects the Meuse surface water level. Drinking water supply is, however, connected to a larger system of abstraction points, such that low flows in the Meuse do not directly affect drinking water capacity. Water use for drinking water accounts for 24% of total water use in the area, see Figure 61.

7.2.6. Total water use

Total water use is summarized in Figure 60 and Figure 61. Figure 60 shows the net water abstraction for each branch, separated by main sectors. Figure 61 shows the total net water abstraction for each sector.

111

Branch Sector Abstraction Return flow Net abstraction M1 Industry 1.2 1.6 -0.4 Agriculture 0.1 0.1 M2 Industry 2.2 -2.2 Energy 4.6 4.0 0.6 Agriculture 0.2 0.2 Drinking water 0.2 0.2 M3 Industry 0.2 0.2 Energy 9.5 -9.5 M4 Agriculture 0.4 0.4 Industry 0.6 0.6 Ju Industry 2.9 0.2 2.7 Agriculture 0.3 0.3 La Drinking water 0.5 0.5 Energy 10.0 10.0 We Agriculture 0.4 0.4 No Industry 0.1 0.1 Agriculture 4.5 4.5 Nature 1.2 1.2 Wi Agriculture 0.7 0.7 Z1 0.0 Z2 Industry 0.3 0.3 0.0 Agriculture 0.6 0.6 Z3 Agriculture 1.1 1.1 Z4 Agriculture 0.6 0.6 A1 Energy 6.0 5.7 0.3 Industry 0.7 0.3 0.4 A2 Industry 0.3 0.3 A3 Industry 0.2 0.1 0.1 Drinking water 5.3 5.3 B1 Agriculture 3.5 3.5 Industry 0.1 0.1 Energy 3.6 3.5 0.1 B2 Industry 0.2 0.2 0.0 Total 57.4 32.5 24.9

Figure 60. Net water abstraction for each branch (m3/s) (Source: Raadgever, 2004)

Sector Abstraction Return flow Net abstraction Total industry 6.8 4.9 1.9 (8%) Total agriculture 12.4 12.4 (50%) Total energy 24.2 22.7 1.5 (6%) Total drinking water 6 6.0 (24%) Total nature 1.2 1.2 (5%) Total 57.4 32.5 24.9

Figure 61. Net water abstraction for each sector (m3/s) (Source: Raadgever, 2004)

112

7.3. THE CONCEPTUAL MODEL FOR THE WATER FLOWS IN THE MEUSE RIVER BASIN

A conceptual model of the Meuse related to water availability for the various water uses is presented in Figure 62. The figure shows all the relevant sub-systems that need to be considered in supporting policy design.

Policy Climate change Population Economic (e.g. WFD) growth growth

Upstream water use

Energy Navigation Drinking Agriculture Industry water

River flow: quantity

Surface water quality

Groundwater quality

Figure 62. Conceptual model of the Meuse related to water use

The main actors are the four water users identified in the previous section. The main external driving forces are at the top of the figure: policy, climate change, population growth and economic growth. They have a direct or indirect effect on the supply and/or demand of water.

7.4. FUNCTIONING OF THE DIFFERENT SUB-SYSTEMS

For individual economic sectors, it is possible to compile a list of driving forces that affect the level of water abstraction from the Meuse by a particular sector. Such a list can clarify: (i) why and how economic activities affect and are affected by the available river flow in the Meuse river basin; and (ii) what drives production and consumption decisions.

These lists are give below, for industry (Figure 63), agriculture (Figure 64), energy (Figure 65), and drinking water (Figure 66). Navigation is not included here, because this sector does not abstract water directly. Also, effects on water quality are not included.

• Surface water abstraction costs • Wastewater storage costs • Wastewater treatment costs • Water abstraction • Non-water input costs • Residual flow • Output prices Industry • Water temperature • Water availability

Figure 63. Driving forces for industry and their effects

113

• groundwater pumping costs • surface water abstraction costs • non-water input costs • output prices • Water abstraction • water availability Agriculture • water quality • government regulations Figure 64 Driving forces for agriculture and their effects

• water temperature • water availability • Water abstraction • residual water storage costs • Residual flow • energy price Energy • production level

Figure 65. Driving forces for energy and their effects

• population • water demand • Water abstraction • groundwater abstraction costs • Drinking water surface water abstraction costs

Figure 66. Driving forces for drinking water and their effects

For the other sub-systems identified in section 7.4, it is also possible to identify similar relationships between input and output variables. For example, the effect of climate change via the combined changes in temperature, precipitation, soil moisture and evaporation on river flow.

7.5. CONCLUSION

In order to further elaborate and quantify the conceptual model, additional information and knowledge on the various subsystems are needed, both on their functioning and the relations between the sub-systems. This need for knowledge is presented in Figure 67, together with the availability of this knowledge within the AquaTerra project and other sources.

114

Knowledge needed Availability in AquaTerra Other

Quantitative assessment of water HYDRO 2 for the Brévilles - inputs and outflows in the basin. catchment, and COMPUTE 3. Water demand for various - Various, e.g. national water economic sectors. authorities in France, Belgium, and the Netherlands. Effects of climate change on river HYDRO 1 - flow Climate change scenarios. HYDRO - Effects of policy change (e.g. EUPOL and INTEGRATOR 1.2 - WFD) on economic sectors. and 2.2 provide a general overview. Detailed models are missing. Effects of economic growth on INTEGRATOR 1.2 and 2.2 - economic sectors. provide a general overview. Detailed models are missing. Effects of population growth on demand for drinking water. Effect of water quality on water - Various, e.g. national water demand by drinking water sector authorities in France, Belgium, and agriculture. and the Netherlands. Effect of economic sectors on - Various, e.g. national water water quality. authorities in France, Belgium, and the Netherlands. Transport and decay of FLUX 1, 2 and 3, and COMPUTE - pollutants in the river system. 3.

Figure 67. Knowledge needs and availability.

REFERENCES

Ansink, E.; Ruijs, A. & van Ierland, E. (2005), 'Anticipated climate, economic and policy changes and their impacts on European river basins', AquaTerra, Sub-project: INTEGRATOR, Deliverable I1.2.

Bouzit, M.; Herivaux, C. & Loubier, S. (2005), 'Meuse River Basin characterisation', AquaTerra, Sub-project: INTEGRATOR, Deliverable I1.1c.

Huisman, P.; De Jong, J. & Wieriks, K. (2000), 'Transboundary cooperation in shared river basins: experiences from the Rhine, Meuse and North Sea', Water Policy 2(1), 83-97.

IMC (2005), 'International River Basin District Meuse – Analysis, Roof Report', International Meuse Commission.

IWAC (2001), 'Assessment practices and environmental status of ten transboundary rivers in Europe', International Water Assessment Centre.

Pfister, L.; Kwadijk, J.; Musy, A.; Bronstert, A. & Hoffmann, L. (2004), 'Climate change, land use change and runoff prediction in the Rhine-Meuse basins', River Research And Applications 20(3), 229-241.

Raadgever, T. (2004), 'Schademodellering laagwater Maas', Royal Haskoning.

RIZA (2005a), 'Watertekortopgave: eindrapport droogtestudie Nederland', RIZA-rapport 2005.015.

RIZA (2005b), 'Aard, ernst en omvang van watertekorten in Nederland', RIZA-rapport 2005.016.

Ministerie van Verkeer en Waterstaat (2004), 'Evaluatienota waterbeheer aanhoudende droogte 2003', Ministerie van Verkeer en Waterstaat, Directoraat Generaal Water.

115

De Wit, M.; Warmerdam, P.; Torfs, P.; Uijlenhoet, R.; Roulin, E.; Cheymol, A.; van Deursen, W.; van Walsum, P.; Ververs, M.; Kwadijk, J. & Buiteveld, H. (2001), 'Effect of climate change on the hydrology of the river Meuse', Wageningen University Environmental Sciences, Sub-Department Water Resources, Report 104.

116

8. Conclusion

The DPSIR framework has been applied as guiding framework to building conceptual models for integrated water management in five case study areas. Overall, it stresses the diversity of conceptual models proposed for the different case studies in terms of the sub-systems considered, the economic sectors influencing or being affected by water resources, the external drivers identified. Figure 68 summarises the main socio-economic sectors that are captured in the conceptual models of the different case studies, along with the main external drivers considered.

Socio-economic sectors Environmental issue Case study area Main external drivers and sub-systems considered considered Agriculture policy Drinking water sector Environmental policy (e.g. Geer Catchment (Meuse, diffuse nitrate pollution in Household water use Nitrates Directive) Walloon region) groundwater Industry (agro-food) Climate change Agriculture Population growth Industrial policy Population (health) Health policy & Kempen area (Meuse, soil contamination by Drinking water sector food safety policy Flanders and Netherlands) heavy metals Agriculture Land planning Urban development Environmental legislation Agriculture policy Tourism development Agriculture soil and surface water Central Ebro River Basin Population growth Drinking water sector degradation because of (Ebro, Spain) Industrial development Industry & public equipments salinity/sodicity Water policy (e.g. National Fishery (?) Hydrological Plan) Population growth Agriculture Tourism development Municipal (household) water Krsko kotlina aquifer groundwater pollution by Agriculture policy service sector (Danube, Slovenia) nitrates and pesticides Environmental & water Disconnected households policy (UWWT & Nitrates Thermal tourism directive) Economic growth Navigation Meuse river basin (Flanders water quality and water Population growth Agriculture & Netherlands quantity (low flows, high Climate change Industry transboundary part) flows) problems Water policy implementation Drinking water

Figure 68. Main socio-economic sub-systems considered in the conceptual models of the INTEGRATOR case studies.

Agriculture and agriculture policy are considered in all case studies – mainly as an economic sector putting pressure on water resources but also as a recipient economic sector influenced by changes in the environmental status of water (see for example in the case of the Ebro where agriculture is both putting pressure via abstraction and being impacted by salinity).

The different conceptual models have been developed with stakeholders input and contribution, via individual interviews or during workshops. However, the final conceptual models developed have not yet been validated globally by stakeholders, by local experts and also by Aquaterra researchers involved in the selected river basins or working on bio-physical processes relevant to the different case study areas. This remains to be done prior to moving forward with the development of quantitative (computer-based) integrated models for selected case studies.

To continue on the development of such integrated conceptual models, we would also need to analyse the needs of quantitative models relating each component of the DPSIR concept. Some of

117

the other AquaTerra Subprojects can provide such inputs (for example, Relationship P-S / mass flux model, within Fluxes and Trend Subprojects).

Risk analysis models used to assess the links between the state of the system and its socio- economic and ecological impacts (i.e. agriculture, public health, and ecosystems) are not studied in the AquaTerra project and in most of the case study, the risks linked to the key impact issues are not quantified (just been described qualitatively). The impact of this lack should assessed in the future.

The R – [DPS] relationship investigates different scenarios of change. First, trends of driving forces, pressures and state have to be modelled and calibrated using statistical approaches or expert-judgement methods. Secondly, these models have to be applied to assess the future impacts of alternative responses and to develop future scenarios.

118

Scientific and Technical Centre Water Division 3, avenue Claude-Guillemin - BP 6009 45060 Orléans Cedex 2 – France – Tel.: +33 (0)2 38 64 34 34