Why some rivers are "flashy" & others are slow to respond

Question 1

When a river floods this measured by a hydrograph.

A flashy river is one that floods quickly. Why?

Answer 1

1. Little vegetation
2. Steep valley sides
3. Intensive rainfall
4. Saturated soils
5. Urban land use
   See if you can name three other factors (page 109 in textbook)

Question 2

A river that has is slow to respond has a long lag time.

What is the lag time?

Answer 2

The time it takes for peak rainfall to peak discharge (in other words from when it rains till the river is at maximum)