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POTENTIAL PRESSURES AND IMPACTS OF ECONOMIC

ACTIVITIES IN ACCORDANCE WITH WFD

D. Cupic 1 and A. Vlasic 2

1 B.Sc. Geol., Croatian Waters, Water Management Institute,

Ulica grada Vukovara 220, 10 000 Zagreb, Croatia E-mail: dcupic@voda.hr

2 B.Sc. Biotech., Croatian Waters, Water Management Institute, Ulica grada Vukovara 220, 10 000 Zagreb, Croatia

E-mail: avlasic@voda.hr ABSTRACT The paper analyzes potential pressures from economic activities and their impact on groundwater bodies in the Kupa River basin, based on a study under the title of “Characterisation of water bodies in the Black Sea basin in the context of implementation of the EU Water Framework Directive” prepared in 2005 by the Croatian Geological Survey, Department of Hydrogeology and Engineering Geology, Zagreb. Geological composition of the Kupa River basin area is described with presented lithostratigraphic units and structural-tectonic features. Hydrogeological characteristics of karst and lowland parts of the basin area are presented through hydrogeological units in terms of their permeability. Groundwater bodies have been selected and characterised in accordance with the requirements of the EU WFD (2000/60/EC), and characterisation approach in the lowland area differs from the one applied in the karst area. A map of natural vulnerability of groundwater bodies in the Kupa River basin has been prepared on the basis of available data. The following potential pressures from economic activities have been selected:

• Point (industry, waste dumps, population), • Diffuse (agriculture, roads), and • Accidental pollution (oil pipeline)

On the basis of all available data analysis has been performed and assessment of risks to groundwater bodies in the Kupa River basin has been made. Keywords: groundwater bodies, vulnerability, pressures, impacts INTRODUCTION Nowadays, at times of ever increasing anthropogenic pollution, caused by population increase, technological development, and modern way of life, the world has, with the aim of protecting water, become a global village with the motto “Think Globally, Act Locally”. It is for that reason, European directives call for the characterisation of

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groundwater bodies in order to assess their use and risks, so as to prevent or limit the input of pollutants into groundwater bodies for the purpose of establishing good general qualitative and quantitative status. Information on water quantity and quality is a basic part of water resources management, particularly in the conditions of sustainable development, which is the basis of the EU Water Framework Directive. The Kupa sub-basin has been selected as a representative sample to demonstrate all the pressures from economic activities and their impact on groundwater quality in the Sava river basin. The aim was to present the accompanying pressures and their impact on groundwater quality on a small area which includes two totally different geomorphological and geological units of the Pannonian basin and the karst area. GEOLOGY AND HYDROGEOLOGY OF THE KUPA RIVER BASIN The Kupa river basin in the karst area consists of the basins of four rivers - the Kupa, Dobra, Mrežnica and Korana Rivers - which converge into one river near the town of Karlovac, at a place where the karstic area of the Pannonian basin turns into a lowland area. The basin’s main characteristic is a complex geologic structure dominated by karstified carbonate aquifers, groundwater flows below drawn impermeable deposit complexes, and occurrences of karst springs with a wide discharge range. A 120-kilometre long range of anticlinal structures spreads from Slovenia to Bosnia with Jurassic dolomites in the core, which represent a full barrier and force groundwater to spring at a range of 12 permanent springs with minimum yields between 0.1 and 1 m3/s on its north-bound course. In hydrogeological terms, in the karst area there are two basic units: a high mountainous area with a specific karst regime and causse, the so called shallow karst. The Kupa River, the largest surface watercourse, advances through a canyon through high mountainous area, while its main tributaries rise from karst springs at a point of contact between the mountainous area and the causse. The hydrogeological map of the basin shows the area of the Outer Dinarides made from carbonate Mesozoic deposits with permeability varying from low to high, and the area of the Inner Dinarides within the Pannonian basin which contains intergranular, Quaternary deposits of medium permeability to practically impermeable pre-Quaternary deposits. CHARACTERIZATION OF GROUNDWATER BODIES The characterization of groundwater bodies was made on the basis of the following elements: hydrogeological boundaries and structures, hydraulic properties of aquifers, groundwater flows, and connection between surface water and groundwater. A groundwater body encompasses an overlying layer as well, while the bottom limit of the water body is T=20°C or 1000 mg/l. The Water Framework Directive (WFD-2000/60/EC) foresees the identification of all groundwater bodies from which more

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than 10 m3 per day can be abstracted. It has been decided that on the national level this shall be the yield of more than 10 litres per day. In that way, 96 groundwater bodies have been identified at first, all of which were grouped into the category of one aquifer in vertical section. The initial characterization of water bodies is based on the geologic and hydraulic properties of aquifers, whereby aquifers with intergranular fracture porosity and karst aquifers are distinguished. Since according to the WFD groundwater monitoring shall be established in each identified groundwater body, and since environmental objectives are to prevent further deterioration and to protect and improve good groundwater status, optimal classification in relation to the potential for groundwater use and pollution has been made according to a model used in the United Kingdom. On the basis of the existing methodology, we have divided the basin on the Kupa area into three aquifer types: principal, secondary and unproductive. In terms of groundwater use we have focused on the principal aquifers (aquifers from which significant quantities of groundwater are used, and which have a significant role in maintaining groundwater ecosystems) and secondary aquifers (aquifers which also have a significant role in groundwater supply, but whose hydrogeological and hydraulic properties may easily lead to their over-exploitation). A map of aquifer types in the basin has been prepared. One of the principal aquifers is the alluvial aquifer of the Kupa River and its tributaries near Karlovac with intergranular porosity and strong hydraulic properties, from which the majority of public water supply is made, as well as carbonate aquifers of fracture-cavernous porosity and high permeability in the zones of high karst with springs of strong yields. Following the analysis of the lithologic structure of top deposits, their thickness, and the preparation of a map of the suitability of top deposits for aquifer protection, a vulnerability map was prepared. The areas of very high vulnerability are open carbonate aquifers of fracture-cavernous porosity and high porosity in the zones of high karst. On the other hand, the areas which are not vulnerable are the areas with unproductive aquifers, and they refer to impermeable rocks found mostly in the north-eastern part of the Kupa river basin.

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Figure 1 Vulnerability of aquifers in the Kupa river basin POTENTIAL PRESSURES AND IMPACTS The identification of pressures in terms of groundwater quality included the following:

• pressures from point sources of pollution (population, industry, waste dumps); • pressures from diffuse sources of pollution (agriculture, roads); • accidental pollution (oil pipelines)

The analysis of pressures included the following activities: assessment of pollution from point sources; assessment of pollution from diffuse sources, including overview of land use; and analysis of other impacts of human activities on water status. Since eventually the analysis of pressures requires a number of parameters, from the exact quantification of pressures, terrane topology, geology, lithologic structure and thickness of top deposits, in case of alluvium, or, in case of karst, the depth to groundwater, and abundance of sinkholes, pits, pedologic layer, vegetation, connection with surface water and a number of other parameters, we have decided that the only safe parameter for the quantification of pressures is the quality of groundwater.

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The main point sources of pollution come from the population: urban wastewater and industrial activities. The database of polluters includes a small number of industrial discharges of wastewater into surface water, which always represent potential danger for groundwater. The dominant activity within the basin is food industry. There are 15 industries. The following users have been identified, systematized by activities, which discharge their wastewater into natural recipients and public drainage systems.

Table 1 Distribution of industry by activities

Food industries Oil and gas Pharmaceutical Metal Textiles Other

Gavrilovi� – Meat

INA Sisak

Pliva-Hrvatski Leskovac Kordun-lav

Pamu�na industrija

Duga Resa

Ogulin General Hospital

PPK – Meat Veterina

Tvornica plinskih

turbine (Gas turbines)

Lola Ribar Duga Resa

Special Hospital

MM Klaonica, prerada i prodaja mesa – Meat-slaughterhouse

ŽE-�E Bjelolasica

Croatian Olympic Centre

KIM – Dairy Karlova�ka pivovara – Brewery

Jamnica – mineral water

Jamnica – spring water and non-alcoholic beverages

At present there are 18 partially constructed combined drainage systems to which 27% of the population is connected, while other wastewater is collected in cesspits or septic tanks. Out of the total number of public drainage systems in the basin, five of them have direct discharges into the underground and as such represent a direct pressure on groundwater. Septic tanks have been analysed as diffuse sources of pollution, and their distribution is seen in Figure 3. Septic tanks have to be considered in relation to overlying layers, or to the assessment of vulnerability of top layers. A direct discharge into the underground has been identified, which represents a direct pressure on groundwater; e.g. wastewater from the Ogulin General Hospital is treated at a biological wastewater treatment plant and is released into an absorbing well. Organized collection of waste

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on the area of the basin covers 14 major large waste disposal sites and a larger number of small local waste disposal sites. Since these waste disposal sites mostly haven’t been constructed in accordance with sanitary requirements, and having also in mind the vulnerability of deposits, they represent a potential pressure. Uncontrolled waste disposal sites for which there is no database represent the greatest danger. All of the above-mentioned pressures from point sources of pollution have been analysed in relation to the vulnerability of overlying deposits, and they were eventually analysed in relation to groundwater quality. For diffuse sources of pollution we used data on agricultural areas (plough-land) and their nitrogen, potassium and phosphorus loads resulting from the application of nutrients for the cultivation of various agricultural crops. The smallest loads from these elements are related to the karst area of the basin. These areas overlap with the identified groundwater bodies, and each groundwater body was assigned an area occupied by one of the land users expressed in percentages. According to European experience, road traffic accounts for over 90% of all traffic pollution emissions, while other forms of traffic (rail, air, ship, maritime, and inland waterways) account for around 10% of the pollution. The share of total pollution load from traffic is small in comparison to other sources of pollution. A motorway runs through the most vulnerable parts of the basin, but there is a defined closed drainage system with grease traps and discharge of treated water into the underground outside of the zones of high protection. A system for monitoring and controlling the operation of the drainage system has to be established. A significant pressure of pollution has been assessed from traffic in the protected areas (in particular: karst springs of drinking water, national parks and nature parks). Roads are potential locations of accidents and spills of oil into the underground, as well as of accidents of special-purpose vehicles transporting petroleum products or other dangerous fluids. The County of Karlovac is a transit area and a junction. A pipeline is one of the potentially significant sources of pollution. It runs along an almost identical route as the motorway. It was constructed in the 1980-ies, and so far there have been no significant accidents which could be registered at drinking water sources. Part of the section of the Adriatic pipeline runs through a sensitive area of shallow karst, where potential pipeline damage represents constant (potential) danger not only for the surface water of large rivers whose beds it crosses and which are essential for supplying the population with water - either directly through surface intakes of open watercourses (the Dobra River near Novigrad, the Mrežnica River near Generalski Stol), or indirectly through the recharge of the abstracted aquifers (the Korana alluvium on the Karlovac water well fields), but also for groundwater in karst aquifers of all downstream catchment areas through which it passes. To the west of the County of Karlovac the pipeline enters into the deep karst part of the Dobra basin, from where potential oil pollution can spread further into the karst regions of the County south of the pipeline – under the ground (predisposed directions from sinkholes near Ravna Gora) and on the surface (Ogulinska Dobra in the direction of Ogulin and �ulin ponor).

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Figure 2 Point sources of pollution Figure 3 Diffuse sources of pollution The detection of pressures and definition of the natural vulnerability of aquifers were followed by an analysis of groundwater quality, particularly for groundwater bodies classified into the category of very high vulnerability. Under the law, the quality of groundwater has to monitored at all of the well fields included in public water supply; however, that scope rarely meets the criteria laid down in the Ordinance on sanitary quality of drinking water (Official Gazette 46/1994). Groundwater quality is monitored only on the well fields used for public water supply, mostly on intake structures (a well or the spring itself). The following indicators from the current monitoring have been selected for the identification of initial chemical status of groundwater and its qualitative status: groundwater temperature; redox conditions in groundwater; mineralization/salinity; groundwater acidity (alkalinity, pH); content of nutrient salts of N (NO3-, NO2-, NH3) and P (total P, orthophosphates); anthropogenic impacts (agriculture, industry, households, waste disposal sites, etc.); heavy metals – Fe – indicator of natural and anthropogenic pollution; chemical oxygen demand; chlorides – proof of impact from agriculture and application of mineral and natural fertilizers, wastewater from roads, households, agriculture, and other indicators – suspended solid matter, turbidity, microbiological indicators, contents of mineral oils. The arithmetic mean reflects the overall status of the groundwater body very well and the reflection of the status which is not exceeded in more than 50% of the area. However, it is unreliable in case of uneven distribution of pollution caused by local or diffuse sources, or in the aquifers of fracture-cavernous porosity. It was nevertheless selected for the initial characterization of groundwater bodies. The quality of groundwater from carbonate aquifers is extremely good, since these aquifers lie mostly in forest-covered mountainous areas, so there is no source of pollution in their catchment area. Karst aquifers are naturally very vulnerable, but if anthropogenic

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impacts are put aside, their natural quality can be upgraded to the highest category. In the upper part of the Kupa river basin springs have been identified on the basis of the origin of groundwater they drain, recharge conditions and exchange of water in the aquifer, and anthropogenic load. The obtained pollution indicators and arithmetic means derived therefrom point to the fact that it is only the springs of the Kupa River and Kupari that are fully free from anthropogenic impact, and their chemical and qualitative status according to the WFD is very high. The concentrations of nitrates, orthophosphates and COD values are characteristic for pure aquifers of the Dinaric karst. The arithmetic means of the indicators monitored at Zamost, Velika Belica, Mala Belica, Kupica and Zeleni Vir springs indicate a slightly poorer chemical and qualitative status. According to the available data, it is obvious that this is a matter of periodical bacteriological pollution, and of occurrence of mineral oils in the springs of Kupica, Mala Belica and Zeleni vir. The greatest amount of pollution is related to septic tanks from the households in the catchment area, and from uncontrolled waste disposal sites. At times of hydrologically higher water heavy precipitation and damp seasons lead to larger pollution, and until the problems related to sewerage infrastructure and uncontrolled waste disposal sites in the catchment area are resolved, the pollution of the above springs is not possible to prevent. Groundwater springing at Žiži�i spring is bacteriologically polluted, which is a threat to its qualitative status, while its chemical status, in terms of the monitored parameters, is very good. Data on the quality of spring water from other monitored springs – Skrad (old intake, Skrad I, Skrad II, Skrad – train station), Frankopan, Glo�evac, Jazbina, Mrzlica, and Veliki Žljeb – point to occasionally poor qualitative status due to high chemical oxygen demand, or due to organic pollution. The springs of Korito and Lokve-Mihi�evo have a slightly better chemical status. However, the available data is not sufficient to assess the chemical and qualitative status of their spring water. CONCLUSION The final product of this paper was assessment of risks for the identified groundwater bodies. The risk assessment was made on the basis of hydrological characteristics, available data on the quantitative status of groundwater, analysis of point or diffuse sources of pollution, and on the basis of available data on the quality of groundwater in particular bodies. A risk assessment map for each body of groundwater represents the final result of conducted analyses and points to the need of implementing measures for achieving good groundwater quantitative status and good groundwater quality status. The optimal risk categorization method selected was the one used in the United Kingdom. All identified groundwater bodies in the Kupa River basin are divided into four categories: significant risk, probably significant risk, no risk, and probably no risk. The category of “Significant risk” contains those groundwater bodies for which real adverse impact on groundwater was identified on the basis of data on groundwater levels and groundwater quality. As for karst areas, two groundwater bodies in the

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Gorski kotar region are classified as being at significant risk (�abranka, Kupica), where an impact of urban wastewater from the surrounding settlements has been identified. The category “Probably significant risk” contains those bodies whose principal aquifers are poorly protected with top deposits, which are subject to significant pressures from land use, while the adverse effect on groundwater quality is not very prominent. The “No risk” category refers mostly to the bodies containing unproductive rocks, as well as to the bodies containing mostly secondary aquifers not subject to significant pressures from land use, in which no adverse impact on the quality of groundwater has been identified. The exception to this is the water body of the source of the Kupa River: even though this is a body of very high vulnerability, there are no potential polluters in the hinterland, since almost the entire water body lies within the boundaries of the Risnjak National Park, which is why this body has been identified as a body with no risk. Groundwater bodies classified as “probably no risk” mostly refer to the bodies containing principal and secondary aquifers used for water supply and which are pretty well protected with top deposits, and where adverse impact on the quality of groundwater was not possible to determine due to insufficient data, but it is assumed that there is no such impact.

Figure 4 Risk map

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REFERENCES 1. Croatian Geological Survey - Zagreb, Water Management Master Plan of the

Republic of Croatia: Hydrogeology, Phase I, 1996. 2. Croatian Geological Survey - Zagreb, Characterisation of the Water Bodies in the

Black Sea River Basin within Implementation of the EU Water Framework Directive, 2005.

3. EU Water Framework Directive, 2000. 4. The Faculty of Mining, Geology and Petroleum Engineering, Groundwater

Registration and Management Project (EGPV): Data for the Kupa river basin, modules: the narrow Kupa River basin and the Korana River basin, the Mrežnica and Dobra River basins, 2000.