The Yellow River Estuary has seen a decrease in runoff and sediment discharge over the past 50 years. By the 1990s, both had significantly decreased. Predictions suggest that in the next 20 years, the average yearly runoff will be less than 15-20 billion m3, and sediment discharge will be less than 0.5-0.7 billion tons per year. The coastline of the Yellow River Delta has also changed historically, and based on these changes and the predicted runoff and sediment discharge, the 0 m coastline is expected to shift in the next 20 years.