The aim of this paper is to study the water market in Canaries in the long run and to show how this resource was managed in the Canary Islands. In the first section, a theoretical model of operation is presented and then is tested to examine the evolution of water prices. We show that the evolution of waterprices is conditioned by the fact that the property of water has been concentrated only in few hands. Finally, we discuss if in the Canary Islands the water has been efficiently managed during XXth century.