Eco-friendly treatment
Standing on a bridge that crosses the grasslands of Pema Lhade village, visitors would find it hard to spot where the embankment is.
The environmentally friendly approach in building the embankment has made it difficult for people to detect traces of artificial construction, said Li Rui, deputy head of Aba's water service center.
Instead of cement, an "ecological bag" was used to build the embankment, which is filled with soil and grass seeds. "A concrete embankment will lead to a complete separation of the river and the wetland around it, cutting the exchange of water between them," he explained.
At a much lower cost, the ecological embankment has proved to work very well, he continued, eyeing the embankment now covered in lush grass, making the ecological bags underneath hardly visible from a distance.
Previously, substantial amounts of soil and sand were left on the riverbank after the floodwaters receded, leading to a continual rise in the riverbed, he explained. Furthermore, the floods eroded grasses along the shoreline, jeopardizing the grasslands that local residents rely on for their livelihoods.
As the most sediment-filled river on Earth, the Yellow River has seen its riverbed rise several meters above the surrounding ground in its lower reaches because of excessive sediment deposits. This makes soil erosion control an important aspect in the management of the Yellow River, though most of the sediment deposits in the 5,464-km waterway are mainly contributed by the Loess Plateau in its middle reaches.
The ecological embankments proved their effectiveness in addressing these challenges after undergoing successful testing over two rainy seasons, Li said, adding they may implement this approach in other areas in the near future.