Flood hydrographs Flashcards
(10 cards)
What can hydrographs be used to understand?
The risk of flooding
What does a flood hydrograph show?
Changes in river discharge after a storm event
What is the typical time period represented in a flood hydrograph?
Usually 24 hours
List the features of a flood hydrograph.
- Base flow
- Peak rainfall
- Rising limb
- Peak discharge
- Lag time
- Recessional limb or falling limb
What factors lead to a short lag time in a flood hydrograph?
Factors which increase surface run off or overland flow
What characteristics are associated with a steep rising limb?
Increased surface run off or overland flow
What does high discharge indicate in a flood hydrograph?
Increased surface run off or overland flow
What factors lead to a longer lag time in a flood hydrograph?
Factors which cause lower surface run off or overland flow
What characteristics are associated with a gentle rising limb?
Lower surface run off or overland flow
What does lower discharge indicate in a flood hydrograph?
Lower surface run off or overland flow
