Thanks to the growth and automation of observational networks and sensors that are more sophisticated, the amount and diversity of data in hydrology is increasing rapidly. These data form the basis for a better understanding of ecological systems and for the development and application of models to describe and forecast changes within these systems. The need of sharing data is widely acknowledged today, though many datasets are still stored on local computers with the corresponding meta information spread over field and lab books. Such data is hardly reusable for other researchers. This makes the collection of data from different sources very time consuming and the necessary additional pre-processing of data enormously slows down the scientific work. In V-FOR-WaTer we develop a web portal to access, scale, and process data, to simplify the gathering of data, speed up the scientific workflow and improve reproducibility of analyses. Our workflow manager facilitates in combination with a detailed documentation the reproducibility of processes and analyses. In addition, we will offer the transfer of data to an established repository, thus encourage publications of data. Today we have a working prototype of the V-FOR-WaTer portal consisting of a customisable metadata model that corresponds to international standards with a focus on hydrological data, a sophisticated data filter, and a toolbox containing basic processes and specialised tools. The portal is being developed in close collaboration between the hydrology group and the computing centre of the Karlsruhe Institute of Technology. This way we maximise performance and usability of the portal, which will create a significant benefit for the environmental science communities.