Coastal currents from big rivers bring sediment to the ocean floor. By studying the Min-Zhe Coastal Current from the Yangtze River, researchers found it carries 18.7 tons of sediment per second. This adds up to 0.27 billion tons of sediment moving south each year, more than three times what the Yangtze River itself releases. This excess sediment might be causing erosion along the East China Sea coast. The erosion seems to be linked to the Three Gorges Dam's impact on the Yangtze River.