Sensitivity analysis of a simplified precipitation-runoff model to estimate water availability in Southern Portuguese watersheds


The water availability estimation in large regions is a relevant procedure to define broad water resources management policies but may prove difficult due to the lack of data and uncertainty to related regional hydrological and hydrogeological characterization. BALSEQ, a daily sequential water budget model, was applied in a set of twenty-two watersheds in southern Portugal, aiming to understand the possible relations between the model parameters and watershed characteristics that may allow assembling calibration functions for non-monitored watersheds. A sensitivity analysis was conducted by comparing BALSEQ results with measured surface flow, focusing specifically on the fraction of the potential maximum retention (φ) and the maximum amount of water available in the soil for evapotranspiration (AGUT) parameters and the underlying hydrogeological conceptual model that ultimately controls the surface-groundwater interactions. The overall results did not allow to identify clear relations that permit extrapolation to other regions without data as the sensitivity analysis procedures returned similar results for wide intervals of parameters for the majority of watersheds. The results confirmed that the groundwater discharge is an important component for the total measured surface flow and that the φ parameter should not be overlooked when calculating direct runoff. Poor adjustments between the model results and measured flow were observed in watersheds with a low Surface flow – Rainfall ratio.



PlumX Metrics


Download data is not yet available.

Author Biography

Maria Manuela Portela, Technical University of Lisbon; UTL · Department of Civil Engineering and Architecture (DECivil)


1. Alam S, Borthakur A, Ravi S, Gebremichael M, Mohanty SK (2021) Managed aquifer recharge implementation criteria to achieve water sustainability. Science of The Total Environment 768, 144992.
2. Beven KJ (2012) Rainfall-Runoff Modelling: The Primer. John Wiley & Sons, Ltd, Chichester, UK.
3. Chachadi AG, Raikar PS, Lobo Ferreira JP, Oliveira MM (2001) GIS and Mathematical Modelling for the Assessment of Groundwater Vulnerability to Pollution: Application to an Indian Case Study Area in Goa. LNEC Report 115/01-GIAS, Lisbon.
4. Chachadi AG, Choudri BS, Lobo Ferreira JP (2005) Estimation of Surface Runoff and Groundwater Recharge in Goa Mining Area Using Daily Sequential Water Balance Model - BALSEQ. Tunnelling and Underground Space Technology, 15.
5. Chow V, Maidment D, Mays L (1988) Applied Hydrology. McGraw-Hill Book Company, New York.
6. Correia FN (1984) Proposta de um método para a determinação de caudais de cheia em pequenas bacias naturais e urbanas “Proposed method for the determination of flood flows in small natural and urban watersheds”. LNEC Technical Report ITH 6, Lisbon.
7. Costa WD, Marinho JM, Castelo Branco RL, Sousa SL, Ramos A, Oliveira MM, Leitão TE, Mendes AC, Martins TAN, Teixeira JAC (2019) Relatório síntese da modelagem numérica (RTP-6) (Relatório de Atividade No. 14), Estudos Hidrogeológicos e de Modelagem Numérica para Identificação do Potencial dos Aquíferos das Bacias Sedimentares de Cedro, Carnaubeira da Penha, Mirandiba e Betânia “Numerical modeling synthesis report (RTP-6) (Activity Report No. 14), Hydrogeological and Numerical Modeling Studies for Identifying the Aquifer Potential of the Cedro, Carnaubeira da Penha, Mirandiba and Betânia Sedimentary Basins”. Secretaria de Desenvolvimento Econômico, Recife, Pernambuco.
8. Moriasi DN, Arnold JG, Van Liew MW, Bingner RL, Harmel RD, Veith TL (2007) Model Evaluation Guidelines for Systematic Quantification of Accuracy in Watershed Simulations. Transactions of the ASABE 50, 885–900.
9. Dillon PJ, Pavelic P, Page D, Beringen H, Ward J (2009) Managed aquifer recharge. An introduction. Waterlines Report Series, 13, 1-64. Available from:
10. Durão RM, Pereira MJ, Costa AC, Delgado J, del Barrio G, Soares A (2010) Spatial-temporal dynamics of precipitation extremes in southern Portugal: a geostatistical assessment study. Int. J. Climatol., 30: 1526-1537pp.
11. Gassert F, Luck M, Landis M, Reig P, Shiao T (2015) Aqueduct Global Maps 2.1: Constructing Decision-Relevant Global Water Risk Indicators. World Resources Institute. Available from:
12. Leitão TE, Oliveira MM, Lobo Ferreira JP, Moinante MJ, Diamantino C, Henriques MJ (2001) Estudo das condições ambientais no estuário do Guadiana e zonas adjacentes. Componente Águas subterrâneas. Diagnóstico da situação actual e identificação da situação de referência “Study of environmental conditions in the Guadiana estuary and adjacent areas. Groundwater component. Diagnosis of the Current Situation and Identification of the Reference Situation”. 2nd Phase LNEC report 212/01-GIAS, Lisbon.
13. Leitão TE, Duarte Costa W, Oliveira MM, Novo ME, Martins T, Henriques MJ, Charneca N, Lobo Ferreira JP, Viseu MT, Santos MAV, Cabral JJ, Freitas Filho A (2017) Estudos sobre a Disponibilidade e Vulnerabilidade dos Recursos Hídricos Subterrâneos da Região Metropolitana do Recife. Relatório da Atividade 9: Síntese dos resultados da modelagem numérica “Studies on the Availability and Vulnerability of Groundwater Resources at the Recife Metropolitan Region. Report on Activity 9: Synthesis of the numerical modelling results”. APAC – Water and Climate Pernambuco Agency. Internal report, Recife, Brazil.
14. Ling, L, Yusop, Z, Yap, W-S, Tan, WL, Chow, MF, Ling, JL (2019) A Calibrated, Watershed-Specific SCS-CN Method: Application to Wangjiaqiao Watershed in the Three Gorges Area, China. Water 12, 60pp.
15. Lobo Ferreira JP (1981) Mathematical Model for the Evaluation of the Recharge of Aquifers in Semiarid Regions with Scarce (Lack) Hydrogeological Data. Proceedings of Euromech 143/2-4 Sept. 1981, Rotterdam, A.A. Balkema (Ed. A. Verruijt & F.B.J. Barends). Also in LNEC Memoir #582 (1982)
16. Maliva R (2014) Economics of Managed Aquifer Recharge. Water 6, 1257–1279.
17. Martins TN, Oliveira MM, Portela MM, Leitão TE (2021) Evaluation of the SCS-Curve Number Distribution in Southern Portuguese Watersheds. 15th Portuguese Water Conference. Portuguese Water Resources Association (APRH), Lisbon.
18. Novo ME, Leitão TE, Tore C, Lobo Ferreira JP (1994) Avaliação dos Recursos hídricos subterrâneos da Ilha da Madeira “Evaluation of the groundwater resources of Madeira Island”. LNEC Report 99/94-GIAS, Lisbon.
19. Oliveira MM. (2004/2006) Recarga de Águas Subterrâneas – Métodos de Avaliação “Groundwater Recharge - Assessment Methods”. LNEC PhD Thesis.
20. Oliveira MM, Moinante MJ, Lobo Ferreira JP (1997) Cartografia automática da vulnerabilidade de aquíferos com base na aplicação do Método DRASTIC “Automatic mapping of aquifer vulnerability based on the application of the DRASTIC Method”. Final report. LNEC 60/97-GIAS, Lisbon.
21. Oliveira, LGS (2007) Soluções para uma gestão adequada de bacias hidrográficas e de sistemas aquíferos, em cenários de escassez hídrica extrema. Aplicação ao sistema aquífero Querença-Silves(Algarve) no âmbito da Acção de Coordenação ASEMWaternet “Solutions for an adequate management of hydrographic basins and aquifer systems, in scenarios of extreme water scarcity. Application to the Querença-Silves aquifer system (Algarve) within the scope of the ASEMWaternet Coordination Action”. MSc dissertation, Instituto Superior Técnico, Lisbon.
22. Oliveira MM, Lobo Ferreira JP (1999) Comparação dos valores de recarga das águas subterrâneas obtidos pela aplicação de diferentes métodos em áreas seleccionadas dentro da área do Plano de Bacia do Tejo “Comparison of groundwater recharge values obtained by applying different methods in selected areas within the area of the Tagus Basin Plan”. Portuguese Groundwater Seminar, Portuguese Water Resources Association (APRH), Lisbon.
23. Page D, Bekele E, Vanderzalm J, Sidhu J (2018) Managed aquifer recharge (MAR) in sustainable urban water management. Water 10, 239.
24. Ponce VM, Hawkins RH (1996) Runoff Curve Number: Has It Reached Maturity? Journal of Hydrologic Engineering 1, 11–19.
25. Portela, MM, Silva, AT, Melim, CP (2000) O Efeito da Ocupação Urbana nos Caudais de Ponta de Cheias Naturais em Pequenas Bacias Hidrográficas “The Effect of Urban Occupation on Peak Flood Flows in Small Hydrographic Basins”. 5th Portuguese Water Congress (APRH), Lisbon.
26. Portuguese Environmental Agency (APA) (2020) Bases do Plano Regional de Eficiência Hídrica – Região do Algarve “Basis of the Regional Water Efficiency Plan - Algarve Region”. Volume I – Descriptive memory. Available from:
27. Ramos C, Reis E (2002) Floods in Southern Portugal: their physical and human causes, impacts and human response. Mitigation and Adaptation Strategies for Global Change 7(3) 267 – 284pp.
28. Santos JF, Pulido‐Calvo I, Portela MM (2010) Spatial and temporal variability of droughts in Portugal, Water Resour. Res., 46, W03503.
29. Trigo RM, DaCamara CC (2000) Circulation weather types and their influence on the precipitation regime in Portugal, Int. J. Climatol., vol. 20.;2-5
30. U.S. Department of Agriculture – Natural Resources Conservation Service (USDA-NRCS) (2004) Estimation of Direct Runoff from Storm Rainfall. Chapter 10. Part 630. National Engineering Handbook. Available from:
31. Vermeulen H, Lobo Ferreira JP, Oliveira MM (1993) A method for estimating aquifer recharge in DRASTIC vulnerability mapping, 1st Portuguese Groundwater Seminar, APRH, Lisbon.
Original Papers
Surface runoff, Aquifer recharge, Hydrological modelling, Daily sequential soil-water budget, BALSEQ
  • Abstract views: 399

  • PDF: 51
How to Cite
Martins, T. N., Mendes Oliveira, M., Portela, M. M., & Eira Leitão, T. (2021). Sensitivity analysis of a simplified precipitation-runoff model to estimate water availability in Southern Portuguese watersheds. Acque Sotterranee - Italian Journal of Groundwater, 10(2), 33-47.