It is well known that the Yellow River, a.k.a. China’s mother river, dumps billions of tons of sediment to the sea and its floods cause havoc on the people along the watershed. Yet I first heard about that China tried to engineer a re-routing of the very end of the river flow right before it reaches the sea, via this NASA Earth Observatory post:
Between 1989 and 1995, the delta became longer and narrower along a southeast-bending arc. In 1996, however, Chinese engineers blocked the main channel and forced the river to veer northeast. By 1999, erosion and settling along the old channel caused the tip of the delta to retreat, while a new peninsula had formed to the north.
The new peninsula thickened in the next five-year interval, and what appears to be aquaculture (dark-colored rectangles) expanded significantly in areas south of the river as of 2004. By 2009, the shoreline northwest of the new river mouth had filled in considerably. This may be the outcome that the engineers were anxious to achieve: the land northwest of the newly fortified shoreline is home to an extensive field of oil and gas wells. Their protection is a primary concern.