PROJECT GROUNDWATER. STUDY VISIT TO MÁLAGA th to 14th of June 2012

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1 PROJECT GROUNDWATER STUDY VISIT TO MÁLAGA th to 14th of June 2012

2 Study Area The study area is in the region of Antequera This region is situated to the north of the province of Málaga It is characterized by abundant mountain reliefs that highlight topographically flat reliefs on the Vega de Antequera set. The mountainous reliefs are mainly limestone mountains which form significant carbonated aquifers. The flat areas are generally comprised of agricultural land and are made up of detritus aquifers.

3 STUDY AREA

4 Peculiarities of the study area The Antequera area is characterized by an abundance of underground aquifers, which are the only source of water supply for the population. This region, although rich in underground water aquifers, faces the frequent inconvenience and severe droughts that affect our region, as does the rest of the province of Málaga. This climate feature determines that groundwater in the area is a strategic natural resource which must be investigated and understood, to take benefit, manage and adequately protect it. The Antequera area presents a general problem based on issues relating to the risk of pollution of groundwater. The eight municipalities included in the present project are those who may be at greater risk and have, on some occasions, shown quality problems, that affect human drinking water.

5 TYPES OF AQUIFERS IN THE STUDY AREA According to the lithology of the formations in which groundwater are found: Carbonated aquifers: dolomitic limestone beds of Jurassic and Triassic reliefs that form topographically steeper and higher reliefs. Their permeability is due to the cracking and kartification processes that affect the formations. Detritus Aquifers: Most recent detritus formations, from the Miocene-Quaternary age, whose permeability is mainly due to the intergranular porosity that they show.

6 AQUIFERS IN THE STUDY AREA The study area consists of groundwater aquifers, near to and including in those municipalities, from where they supply all or part of the water. These aquifers are part of the so-called Bodies of Groundwater (MASb), from administrative point of view. The Bodies of Groundwater delineated in the province which are involved, directly or indirectly, in the population water supply of the previously defined Municipalities, are:

7 AQUIFERS IN THE AREA MAS Flat of Antequera Fertil plaine of Archidona (composed of both, detritus and carbonated aquifers ) MAS Mountain of Teba-Almárgen-Campillos (composed of both, detritus and carbonated aquifers ) MAS Fuente de Piedra (composed of both, detritus and carbonated aquifers ) MAS Mountain and Miocene of Estepa (composed of both, detritus and carbonated aquifers ) MAS Mountain of Archidona (carbonated aquifers) MAS Pedroso-Arcas (made up of carbonated aquifers) MAS Torcal of Antequera (made up of carbonated aquifers) MAS Mountain of Cañete (made up of carbonated aquifers)

8 Type of water bodies in province MALAGA. Detritus Alluvial, coastal and other pliocuaternarious deposits Detritus tables of Neogene basins Carbonated Metamorphic Folded sedimentaries (Mesozoic and Cenozoic) Metamorphic Metamorphic non carbonates (metasediments) Mixed Metasedimentary and detritus Carbonates and Detritus

9 Type of water bodies. Detritus Alluvial, coastal and other pliocuaternarious deposits Detritus tables of Neogene basins Carbonated Metamorphic Folded sedimentaries (Mesozoic and Cenozoic) Metamorphic Metamorphic non carbonates (metasediments) Mixed Metasedimentary and detritus Carbonates and Detritus

10 Age Lithology Permeability Quarternary 10. Travetine High Quarternary 9. Alluvial High Quarternary 8. Undifferentia ted Medium Miocene Cretaceous/Miocene Jurassic/Cretaceous Jurassic Jurassic Triassic Triassic 7. Calcarenites, Conglomerat es & Marl 6. Clays and sandstones 5. Marl and marlaceous lime 4. Limestone 3. Dolomites 2. Limestone and dolomites 1. Clays and Chalk Medium Very low Low High-very high High Medium-High Low

11 AQUIFERS OF STUDY AREA

12 Exploitation and best use of groundwater for supply Springs Sounding and boreholes Galleries The eight municipalities where the PGW project will be curry out is exclusively supplied by groundwater.

13 Supply systems in the analysed municipalities Municipality Catchment Aquifer Type of aquifer Alameda 2 boreholes Mollina-Alameda Carbonated Almargen 2 boreholes Mountain of Cañete Carbonated Antequera 2 springs 7 boreholes Torcal of Antequera Flat of Antequera-Archidona Carbonated Detritus Archidona 3 boreholes 1 gallery Sierra de Archidona Flat of Antequera-Archidona Carbonated Detritus Campillos 1 spring Mountain of Cañete Carbonated 2 boreholes Mountain of Peñarrubia Cuevas Bajas 2 boreholes 1 spring-gallery Flat of Antequera-Archidona Pedroso-Arcas Detritus Carbonated Sierra de Yeguas 2 boreholes Mountain of Caballos Carbonated Villanueva Tapia 1 borehole Mountain of Archidona Carbonated

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15 Spring of Majavea (Campillos) Borehole of Sierra de Yeguas Borehole of Cuevas Bajas Borehole of Villanueva de Tapia

16 Vulneralbility to pollution Vulneralbility to pollution is down to the aquifer s susceptibility to pollution as a result of human activity. The vulnerabilitly is determined by a number of characteristics of the area: geological, geomorphological, hydrogeological, climatic and biological.

17 Vulnerability map of Malaga s aquifers Vulnerability level Limit and code water bodies Very high High Moderate Low Very low

18 The aquifers in the Antequera region have a very high vulnerability in certain areas (limestone aquifers), with overall vulnerability being between high and moderate, for most of its surface.

19 Main sources of pollution Agriculture Livestock Urban activity (dumping of wastewater and solid waste, camping, etc.) Intensive exploitation of boreholes

20 Pollution in the target municipalities The main pollution sources, that may affect water supply intended to urban catchment areas, for the selected municipalities in the project, are: Pollution as a result of agricultural activities (pollutants are fertilizers, pesticides, irrigation with wastewater). They involve increased concentration of nitrates, phosphates, heavy metals, organic matter and suspended solids. Pollution as a result of livestock activities (intensive livestock, mainly pigs), linked mainly to its waste (manure). Pollutants from this activity are nitrogen compounds, heavy metals and chemicals and pharmaceuticals.

21 IRRIGATION SLURRY DREGS PONDS SLURRY PONDS DREGS PONDS

22 In all the analysed municipalities they have pollution problems of this type, although the timing of these episodes are calculable, in no case does it affect catchments destined for urban supply

23 Pollution as a result of urban activity: urban waste water dumping (UWW), dumping of municipal solid waste (MSW), cemeteries, camping They are associated with high contents of nutrients (N and P), organic matter and microbiologic contamination. The leaching generated by the MSW is characterized by a high salt content (Na +, NH4 +, Cl-) and heavy metals (Fe and Mn) The municipal solid waste is currently being satisfactorily managed through the installation of MSW controlled landfills located in suitable places from a hydrogeological point of view With regards to urban waste water, most of the municipalities covered by the project already have UWW treatment plants. Pollution of a natural origin: salination of sweet aquifers are as a result of over-exploitation at great depths, drawing salty water deposits linked to existing Triassic gypsum in this region.

24 UWW TREATMENT PLANT OF ALAMEDA VALSEQUILLO ENVIRONMENTAL COMPLEX

25 With this project, it will be necessary to update a detailed inventory of all focal points and sources of groundwater pollution in the target municipalities. It is also essential to define supply systems in each one and their position in relation to focal points and pressures. It intends to carry out a diagnosis of the quality of groundwater by relating it to human activities and land uses developed in their areas of influence. The final aim should be to define the risk of pollution of aquifers in each municipality and propose the necessary measures and actions to mitigate and/or avoid the hazard.