NIWA is developing numerical models for predicting how the morphology of braided rivers responds to flow regulation and invasive exotic woody vegetation. This numerical simulation of the evolution of a fluvial reach at laboratory scale starts from an initially straight channel (Tal and Paola, 2010), using the modified GIAMT2D model. The first phase is about the development of a braided network in a bare, cohesionless sand bed. The second phase is composed of 31 cycles of vegetation growth at low flow, each one followed by a short high-flow phase which removes vegetation within channels, by which the braiding morphology progressively reduces to much a more static morphology with reduced braiding intensity. For further information visit niwa.co.nz/node/111731