Evaluation du risque de conflit autour des eaux transfrontalières du système aquifère du Sahara Septentrional (SASS)., ISSN 1112-3680, June 2015,

Citation:

redha, MENANI Mohamed. 2015. “Evaluation du risque de conflit autour des eaux transfrontalières du système aquifère du Sahara Septentrional (SASS)., ISSN 1112-3680, June 2015,”. Larhyss Journal (n°22) : pp. 59-69.

Abstract:

Le SASS couvre une superficie d’environ 1000000 km², ilest partagé parl’Algérie, la Libye et la Tunisie. Il est situé dans une zone hyper aride avec unerecharge actuelle minime mais un grand volume stocké, évalué entre 20000 et31000 km3.Depuis 1970 à nos jours, l’exploitation du SASS est passée de 0,6 àplus de2,5milliards m3/an., d’oùdesrisques majeursdesalinisation des eaux,deréduction de l’artésianisme,detarissement des exutoires naturels,debaisse dela piézométrie,d’augmentation des rabattements oud’interférencesdespérimètres de captageentre pays...Ce qui menace à terme la durabilité dudéveloppement socio-économique engagé dans l’ensemble de la zone.Pour parer aumieux à ces risques et surtout pour mieux s’enprémunir, unprocessus de coopération a été initiédepuis 1998sous l’égide de l’observatoiredu Sahara septentrional(OSS)en partenariat avec les institutions en charge desressources en eau dans les 3 pays.L’importance de cet immense réservoir pour le développement de la zone SASSet la nécessité de sa gestion durable et concertée a amené à une entente pour sonétude enplusieurs phases: la caractérisation hydrogéologique du systèmeaquifère et sa modélisation, l’identification des risques environnementaux etl’inclusion de l’aspect socio-économique dans des scénarios de développement.Les ressources en eau du SASS sont très faiblement renouvelables,environ1milliard dem3/an, vis-à-vis des prélèvements actuels estimés à 2,5 milliards dem3/an. La prise en compte de cette donnéea été déterminante pour pousser lesscientifiques à établir la meilleure modélisation conceptuelle possible dusystème qui soit à même de permettre d’envisager différents scénariosd’exploitation de la ressource tout en tenant compte des perspectives de développement socio-économique de chacun des 3 pays.Les données actuelles, quoique rassurantes, ne signifient pas l’inexistence, àcourt ou moyen terme, d’un risque de conflit autour de ces eauxtransfrontalières. En effet, le problème mérite d’être analysé à travers plusieursindicateurs qui ont un impact sur ce risque.L’objectif de cette note est d’évaluer le risque de conflit autour des eaux duSASS à travers un indice global exprimé numériquement sur la base de lacombinaison de poids et de cotes de plusieurs indicateurs qui ont, directementou indirectement, un impact sur le risque de conflit.L’indice global de risque de conflit obtenu pour le cas du SASS semble reflétercorrectement la situation quiyprévaut actuellement.La comparaison de cerésultat avec ceux obtenus pour les eaux transfrontalières du bassin du Jourdain(risque élevé) et ceux du système aquifère du Guarani (risque faible), confortel’échelle des valeurs adoptée dans cette méthode d’indexation numérique.

Publisher's Version

Last updated on 02/19/2019

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