Abstract -- Groundsill is one of the common structures implemented for river training and flow regulation. Nevertheless, it divides a stream into segments that surely affect the aquatic habitat. Natural streams often follow the principles of self-adjustment in morphology. They tend to be meandering even after artificial training. As the results, riffle-pool sequences eventually provide a natural environment for river rehabilitation. The objective of this research is to assess the applicability of open-slot groundsills in a trained river to encourage the formation of mean-dering.
Preliminary results of this study indicate that selective transport occurs along the banks of thalweg after the installation of open-slot groundsills. In the meantime, selective deposition occurs at the floodplain outside the thalweg. Both of them encourage the formation of point bars and meander, which result in greater diversity in a trained channel. For those that meander can be successfully generated, the width of the scour was able to control in the range of 2 to 4 times the opening’s width. The depth of the scour was also able to reach about the same elevation of the bottom of the opening. However, as the sediment becomes finer, width of the twalweg diverges as groundsill interval increase.