The outflow from the Xiaolangdi Dam in central China’s Henan Province has turned from clear to turbid, signaling the start of the 2025 pre-flood water and sediment regulation phase of the Yellow River. This annual operation, set to continue until July 9, will see over 100 million tonnes of sediment discharged downstream.
The sediment flushing process is crucial for maintaining the health of the Yellow River, often called China’s “Mother River.” Over time, sediment accumulates in the Xiaolangdi Reservoir, reducing its capacity and potentially impacting flood control and water supply. By releasing sediment-laden water, the dam helps prevent clogging and ensures a smoother flow during the flood season.
So, how does the Xiaolangdi Dam flush out the accumulated sediment? The dam employs a technique where it releases water at high speeds through its bottom outlets. This powerful flow scours the riverbed, picking up sediment and carrying it downstream. The process not only clears the reservoir but also replenishes sediment in lower reaches, which is vital for maintaining the river’s ecological balance.
After the sediment discharge concludes, dam authorities will monitor the river’s conditions to assess the operation’s effectiveness. Maintenance work may be conducted to prepare for the upcoming flood season, ensuring the dam continues to function safely and efficiently.
The annual sediment flush at Xiaolangdi Dam is a remarkable example of human ingenuity working in harmony with nature, highlighting efforts to manage and preserve one of the world’s most significant rivers.
