 To address water pollution in Chinese rivers and lakes, a virtual geographic environment, VGE, is proposed to integrate heterogeneous hydrological data sets for easy access, evaluation of simulation results, and identification of interrelations or inconsistencies between data sets. A prototype VGE has been set up for Chao Lake with more than 20 spatial data sets and successfully presented to Chinese and German researchers and stakeholders. This article was authored by Karsten Rink, Kui Chen, Lars Bilke, and others.