Following the success of the 1st Symposium in Hong Kong in 1991, the series has been established as a major event bringing together engineers and scientists working on a variety of fundamental problems related to the water environment. The field of Environmental Hydraulics has expanded considerably over the last two decades owing to the growing concern over water environmental issues associated with pollution and water balance problems on a regional and global scale, which require a thorough understanding of processes related to environmental flows and transport phenomena and the development of new approaches for practical solutions. The 6th ISEH aims at addressing these challenges.