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  • Estimating harvested rainwater at greenhouses in south Portugal aquifer Campina de Faro for potential infiltration in Managed Aquifer Recharge
    Publication . Costa, Luís; Monteiro, José Paulo; Leitão, Teresa; Lobo-Ferreira, João Paulo; Oliveira, Manuel; Carvalho, José Martins de; Carvalho, Tiago Martins de; Agostinho, Rui
    The Campina de Faro (CF) aquifer system, located on the south coast of Portugal, is an important source of groundwater, mostly used for agriculture purposes. In some areas, this multi-layered aquifer is contaminated with high concentration of nitrates, possibly arising from excessive usage of fertilizers, reaching to values as high as 300 mg/L.
  • Modeling nitrate-contaminated groundwater discharge to the Ria Formosa Coastal Lagoon (Algarve, Portugal)
    Publication . Hugman, Rui; Stigter, Tibor; Costa, Luis; Monteiro, José Paulo
    A numerical flow and transport model is developed to assess groundwater discharge and nutrient transport to the Ria Formosa coastal lagoon in southern Portugal. A total N load of 350 ton/year is estimated for the considered area, of which agriculture accounts for 73% of total N load, and domestic effluent and atmospheric deposition for the remaining 9% and 18% respectively. Model results suggest that nutrient recycling has led to the high concentrations observed in the Campina de Faro (M12) aquifer, but is still insufficient to account for observed values at the coastline. Furthermore results suggest that even for the best case mitigation scenario, good quality status will not be achieved by 2027, as mandated by the EU Water Framework Directive.
  • Environmental impacts on soil and groundwater at airports: origin, contaminants of concern and environmental risks
    Publication . Nunes, L.; Zhu, Y.-G.; Stigter, T. Y.; Monteiro, José Paulo; Ribau Teixeira, Margarida
    Environmental impacts of airports are similar to those of many industries, though their operations expand over a very large area. Most international impact assessment studies and environmental management programmes have been giving less focus on the impacts to soil and groundwater than desirable. This may be the result of the large attention given to air and noise pollution, relegating other environmental descriptors to a second role, even when the first are comparatively less relevant. One reason that contributes to such ‘‘biased’’ evaluation is the lack of systematic information about impacts to soil and groundwater from airport activities, something the present study intends to help correct. Results presented here include the review of over seven hundred documents and online databases, with the objective of obtaining the following information to support environmental studies: (i) which operations are responsible for chemical releases?; (ii) where are these releases located?; (iii) which contaminants of concern are released?; (iv) what are the associated environmental risks? Results showed that the main impacts occur as a result of fuel storage, stormwater runoff and drainage systems, fuel hydrant systems, fuel transport and refuelling, atmospheric deposition, rescue and fire fighting training areas, winter operations, electrical substations, storage of chemical products by airport owners or tenants, and maintenance of green areas. A new method for ranking environmental risks of organic substances, based on chemical properties, is proposed and applied. Results show that the contaminants with the highest risks are the perfluorochemicals, benzene, trichloroethylene and CCl4.
  • Interpretation of an injection test in a large diameter well in south Portugal and contribution to the understanding of the local hydrogeology
    Publication . Costa, Luís R. D.; Monteiro, José Paulo; Oliveira, Manuel M.; Ferreira, João Paulo Lobo; Leitão, Teresa E.; Carvalho, Tiago; Carvalho, José Martins de; Agostinho, Rui
    This paper refers to the interpretation of an injection test in a traditional large diameter well in Querença-Silves aquifer, south Portugal, under the scope of the project FP7-ENV-2013-WATER-INNO-DEMO MARSOL. Hydraulic parameter estimates were found within a high level of uncertainty regarding aquifer and well configuration. Given the injection test results together with the knowledge acquired on the field and from previous well logs and pumping tests on this aquifer section, it seems plausible to assume that the water injected in the well is locally flowing to an opposite direction to the regional aquifer flow. This forcing could possibly be caused by the existence of a local confinement or aquitard separating the injection well from the regional aquifer, or simply due to local scale heterogeneities and fracturation patterns.
  • Quantifying and modelling the contribution of streams that recharge the Querenca-Silves aquifer in the south of Portugal
    Publication . Salvador, Nuria; Monteiro, José Paulo; Hugman, Rui; Stigter, Tibor; Reis, E.
    The water balance of the mesocenozoic aquifers of the Algarve, in the south of Portugal has traditionally been estimated considering only direct ("autogenic") recharge from rainfall occurring in the area of the aquifers. Little importance has been attributed to so-called allogenic recharge, originating from streambed infiltration from runoff generated outside the aquifers, particularly in the Palaeozoic rocks to the north where runoff is high. The Querenca-Silves (QS) aquifer is the most important aquifer of the region both for irrigation and public water supply. Several important and sensitive surface/groundwater ecotones and associated groundwater dependent ecosystems exist at the springs of the natural discharge areas of the aquifer system. A numerical flow model has been in constant development over the last few years and currently is able to reproduce the aquifer's responses to estimated direct recharge and abstraction for the years 2001-2010. However, recharge calculations for the model do not take into account allogenic recharge infiltration along influent reaches of streams. The quantification of allogenic recharge may further improve the assessment of water availability and exploitation risks. In this paper an attempt is made to quantify the average annual contribution of allogenic recharge to the QS aquifer, based on monitoring data of the principal water courses that cross the aquifer system. Significant uncertainties related to surface runoff generated within the aquifer area, as well as areal recharge were identified and the consequences for the optimization of spatial distribution of transmissivity in the groundwater flow model are also addressed.
  • The water crisis in southern Portugal: how did we get there and how should we solve it
    Publication . Nunes, Luís; Monteiro, José Paulo; Cunha, M. C.; Vieira, J.; Lucas, H.; Ribeiro, L.; Brebbia, C. A.; Conti, M. E.; Tiezzi, E.
    Until very recently, the public water supply in the Algarve region was almost entirely supported by groundwater wells. However, in the last years of the 20th Century, the Portuguese government defined a scheme for the public water supply sector entirely based on surface water from large dams, in order to guarantee the public water supply. The efforts to abandon groundwater as a source for public supply started in 1998, after a large investment in new infrastructures and rehabilitation of some existing ones. However, the practical implementation of this water supply scheme showed that an integrated resource management is needed in order to implement a more economical and reliable solution. The present paper describes the historical background and the evolution of water use in recent decades until the present time in the Algarve, and a proposal for restructuring the management of the water supplies based on the development of a decision support system within an integrated water resources management scheme.
  • Re-Assessing coastal groundwater management policy in the Algarve: estimating the potential for seawater intrusion
    Publication . Hugman, Rui; Viegas, João; Gois, António; Costa, Luis; Monteiro, José Paulo; Stigter, Tibor
    Groundwater supplies about 70% of the fresh water needs in Portugal with most of the aquifers occurring at the coastline, where more than 60% of the whole population dwells. The overexploitation of groundwater resources during the final decades of the 20th century, lead to a gradual decrease in water quality in many coastal aquifers of the Algarve, the southernmost region of Portugal.
  • Recursos hídricos
    Publication . Cunha, Luís V.; Ribeiro, Luís; Oliveira, Ricardo P.; Nascimento, João; Monteiro, José Paulo; Dill, Amélia Maria Mello de Carvalho; Nunes, L.
    O Projecto "Climate Change in Portugal. Scenarios, Impacts and Adaptation Measures" (SIAM) iniciou-se em meados de 1999, com o financiamento da Fundação Calouste Gulbenkian e da Fundação para a Ciência e a Tecnologia. O Projecto SIAM teve como objectivo a realização da primeira avaliação integrada dos impactos e medidas de adaptação às alterações climáticas em Portugal Continental no século XXI. Os estudos realizados basearam-se em cenários do clima futuro obtidos a partir de modelos de circulação geral da atmosfera e incidiram sobre um conjunto de sectores sócio-económicos e sistemas biofísicos designadamente: recursos hídricos, zonas costeiras, agricultura, saúde humana, energia, florestas e biodiversidade e pescas. Foi também realizada uma análise sociológica sobre a problemática das alterações climáticas em Portugal. As principais conclusões obtidas no Projecto SIAM foram publicadas num Sumário Executivo e Conclusões, lançado em Outubro de 2001, editado em português e em inglês.A segunda fase do Projecto SIAM (SIAM II) iniciou-se em Janeiro de 2002. Esta segunda fase focou-se no estudo de caso do Estuário do Sado, tendo os estudos sido alargados às Regiões Autónomas da Madeira e dos Açores. O SIAM II incluiu ainda uma componente de Outreach que teve como objectivo a divulgação dos resultados obtidos no SIAM I aos diversos agentes interessados, obtendo ainda inputs para o SIAM II, através da organização de reuniões nas quais participaram as equipas dos sectores considerados relevantes para a região escolhida e os respectivos agentes interessados. O SIAM II foi financiado pelo Instituto do Ambiente, do Ministério das Cidades, do Ordenamento do Território e Ambiente.
  • Assessing the use of harvested greenhouse runoff for managed aquifer recharge to improve groundwater status in South Portugal
    Publication . Costa, Luis; P. Monteiro, J.; Hugman, Rui Twohig
    Concentration of nitrates in groundwater at the Nitrate Vulnerable zone of Faro, south Portugal, reaches values as high as 300 mg/l; therefore, according to the EU Water Framework Directive, mitigation measures need to be implemented. A Managed Aquifer Recharge scheme is proposed to accelerate the dilution and natural discharge of nitrates from the system. Source water availability is estimated from rainfall intercepted at existing greenhouses. Within the highest nitrate concentration area, estimated water availability for injection in existing wells is 1.50 hm(3)/year, a significant volume which represents approximately 15% of the aquifer direct recharge. It is proposed this is recharged to the aquifer through existing large-diameter traditional wells that are no longer used for abstraction. Injection test results suggest that the likely infiltration capacity of such wells is more than sufficient to allow collection of 95% of daily rainfall events. The effect of injecting this volume in the aquifer was estimated with the support of a 3D numerical groundwater flow and transport model. Results show considerable improvement in nitrate concentrations in the study area, in certain locations decreasing up to 70 mg/l by 2027. The model results predict a decrease in the number of nitrate threshold exceedances in observation points, from 33 to 30 by 2027 and 14 to 9 by 2040. It is likely that this measure may have a positive effect on other issues identified in the area, mostly related with quantity problems and seawater intrusion. Notwithstanding, issues including landowner support, clogging, conditions of greenhouses and wells, water quality, and climate change impacts will require further consideration to develop a successful and beneficial MAR scheme.
  • The water crisis in southern Portugal: how did we get there and how should we solve it
    Publication . Nunes, Luís; Monteiro, José Paulo; Cunha, Maria da Conceição; Vieira, João; Lucas, Helena; Ribeiro, Luís
    Until very recently, public water supply in the Algarve region was almost entirely supported by groundwater wells. However, in the last years of the XX Century, the Portuguese central administration defined a scheme for the public water supply sector entirely based in surface water from large dams, in order to guarantee the public water supply. The efforts to abandon groundwater as a source for public supply started in 1998, after a large investment in new infrastructures and rehabilitation of other ones. However, the practical implementation of this water supply scheme showed that an integrated resource management is needed in order to implement a more economical and reliable solution. The present paper describes the historical background and the evolution of water use in the last decades until the present time in the Algarve, and a proposal for restructuring the management of the water supplies based in the development of a decision support system in the scope of an integrated water resources management.