I'm pretty sure you can, my geography teacher thinks it was a question to get us to explain how the drainage basin can be changed and influenced so looking into land use for impermeable surfaces or vegetated land and how they may hinder or help flows and transfers, looking at land values as they can indicate the intensity of flood management techniques in the area and how they affect the flow, whether the river has been altered upstream with something like a dam which controls the flow, precipitation levels etc