Flood Hydrogrpahs Flashcards
What is lag time
The delay between peak rainfall and peak river discharge, as it takes time for water to flow into the river
What is peak discharge
Volume of water in the river is at its greatest
What is peak rainfall
Rainfall is at its greatest
What is discharge line
The volume of water in the river
What is the rising limb
River discharge increasing
What is the falling limb
Discharge reducing as less water is flowing into the river
What is bank-full discharge
River begins to overflow, depending on the river
What is base flow
Normal discharge of the river
What are factors that can affect a flood hydrograph
Shape of drainage basin - a circular drainage basin leads to rapid water drainage, whereas a longer basin will take the water in more slowly
Topography - the steeper the basin the quicker water will drain
Heavy rainfall - increase peak disachge and bankfull disachge drastically
Vegetation - intercepts precipitation, and slows the movement of water entering channels
Dry soil - prevents water from reaching the channel, slowing down lag- time
