Mustapha Besbes is hydrogeologist, emeritus Professor at the National Engineering School of Tunis, University of Tunis El Manar. He received the PhD in Hydrology (1967) and the Doctorat es sciences from the University Pierre & Marie Curie in Paris (1978). Pr Besbes was elected Foreign Member of the French Academy of sciences in 2009, and member of the Tunisian Academy of Sciences, Letters and Arts in 2013. World leader in arid zone hydrology, he coordinated the NWSAS (North Western Sahara Aquifer System) modeling process in the 2000s. He has published books and articles in hydrogeology and water management. He is chairman, reviewer or associate editor of journals in hydrological sciences. Mustapha Besbes is member or head of numerous scientific commissions, councils, boards and task forces. Jamel Chahed is a hydraulics engineer and Doctor es sciences, Professor at the National Engineering School of Tunis, University of Tunis El Manar.His work focuses on transfers in industrial and environmental fluid systems, atmospheric dispersion, water governance and water management. His research has appeared as articles, books, book chapters, conference acts in specialized literature such as hydrology, water resources management, hydraulics, turbulence and transfers, environmental engineering. He actively contributed to the development of long-term vision for water security with a thematic focus on holistic water balance assessment. He has been involved in number of national and international academic research and technical programs. As visiting professor, associate researcher or guest speaker he joined number of international research teams at academic institutes, research laboratories and R&D centres.Abdelkader Hamdane is graduated from Institut National Agronomique de Paris (1971), and Ecole Nationale du Génie Rural, des Eaux et Forêts de Paris (1973). He is general engineer, formerly General Directorof the Medjerda Valley Development Company, General Director of Rural Engineering and Water Management Department of the Ministry of Agriculture and Water Resources of Tunisia. He has been member of several public companies boards operating in the field of water, and led several assessment missions in scientific and technical research institutions. He was a short-term professor of irrigation and drainage at the National Agronomic Institute of Tunis and the National Engineering School of Tunis. He is currently a Scientific Advisor at the National Agronomic Institute of Tunis, University of Carthage, involved in many national and international research programs, and consultant on water management in international organizations.