In the framework contract between the Company Maunsell Pty Ltd (Australia) and the Center for River Engineering Research - Institute of Water Resources (former), the morphology research in Tien river in My Thuan bridge area has been conducted 1996 before the construction of bridge. These include "Study of large scour hole movement in Tien river ...". Large scour hole upstream of the My Thuan bridge, 48 meters deep as the deepest point. Because changes in the position of the scour hole could lead to lower depth at the position of the river bed at the bridge site, problems should have studied: - History of the movement of the river has created a surface contraction wide river from the fen)' to the bridge position
the river width contraction has led to deep river impacts
- the bends in the river fen)' was located at the downstream effects on the deoth of the river bed
- the position and shape of the scour hole is closely related with the appearance by the river and in particular river width contraction led and location of the river bend. Thus, the stability of the northern bank upstream of the key factors to reduce risks due to changes in position or shape of the scour hole caused in the future. From research, building a stable world Tien river of My Thuan bridge area was conducted before and during bridge construction. So far Tien river position of My TIman bridge area has been stable. but due to factors not only changes in the river as by a natural rule, but also human impacts is very complex, the Tien liver form monitoring and the My Thuan bridge area should also be continued.