In the search for sustainable city solutions, engineers face a bottleneck situation in balancing development and the intensified environmental challenges induced by scaled-up flooding, over-grown river vegetation, sediment transport, bridge and coastal scouring, and excessive pollution. The coupling impacts of uncontrolled flood and sediment to a city has caused difficulty in its management. Various numerical, theoretical, and experimental approaches have been proposed to reproduce flow and sediment transport conditions in real-world urban rivers, in order to perfect management strategies for them. This reprint, which is built from a well-planned journal's Special Issue, aims to construct a collection of state-of-the-art studies and technologies to give insights to the related environmental, river, and sustainable city research and engineering communities. It is related and, hence, useful for environmental, river, and hydraulic engineers, authorities, and researchers to understand the current state-of-the-art practices in urbanized flow modelling, as well as vegetation- and sediment-related management. It also serves as a good knowledge source for research, post- or undergraduate students, in terms of knowledge about the most up-to-date topical advances.