Drainage Basin - Physical Impacts

• If the area contains dense vegetation, this will increase interception which slows down the rate of surface run-off, making the water take longer to return to the river.
• If the area contains sparse vegetation, this will lead to soil saturation and increase rates of surface run-off as the area begins to flood with lack of interception.
• Impermeable soil/rock reduce infiltration and increase surface run-off to the river.
• Permeable soil/rock allows infiltration, meaning the water can return to the river through throughflow, groundwater flow or percolation as the water travels back to the river at a slower rate.
• If the land is steep, surface run-off will be faster due to gravity.
• Gently sloping land means water will travel back to the river slower due to slower rates of surface run-off. This can lead to increased rates of infiltration as water sits on the surface for longer
• A hot, dry climate will cause water to be evaporated, decreasing river levels.
• A wet climate will cause increased precipitation, increasing river levels.