A major concern for companies and governments is the robustness of their activities and investments in view of a changing climate. The water sector is in need of technological innovations to be able to cope with the effects of changing climate on the water system. IBM is searching for a way to utilize the computational power of its supercomputers and its expertise and capabilities on sensor networking, date streaming and visualization, to satisfy the needs of the water sector. Commissioned by IBM, the Centre for Water and Climate of Wageningen University and Research Centre (WUR) has carried out a study in cooperation with European research partners that resulted in this position paper. The aim of the paper is to present an overview of the opportunities for improving and utilizing monitoring systems and sensors, weather/climate prediction systems, and their coupling to hydrologic models, hydrological forecasting tools and use in water management. In Europe water-related issues are dealt with in international collaboration, both institutionally and scientifically, with countries like Germany, United Kingdom, Denmark, Norway, France, the Netherlands, etc. In this paper we focus on the water sector in the Netherlands within this European context