How do you explain a hydrograph?
A hydrograph is a graph showing stage discharge Volume of runoff, or other properties of water flow with respect to time. When the stage is plotted against time, the graph is a stage hydrograph. When the discharge is shown against time, the graph is a discharge hydrograph.
Why do hydrographs differ?
Hydrographs can take different shapes dependent upon the characteristics of the drainage basin. The various flows and stores of the drainage basin are affected by these characteristics, and these in turn will affect the shape of the hydrograph and the volume of water in a river.
What are the characteristics of flood hydrographs?
Flashy hydrographs have a steep rising limb and a small lag time. This indicates the river discharge increases rapidly over a short period of time, indicating rainwater reaches the river very quickly. This means the river is more likely to flood.
Why do we study hydrographs?
Basically, a hydrograph shows you the ways in which a river is affected by a storm. This helps us to understand discharge patterns of a particular drainage basin and helps to predict flooding and plan flood prevention measures.
What are the three main components of a hydrograph?
There are three main components to the hydrograph—rising limb, peak, and falling limb. The falling limb is often referred to as the recession curve, which provides information on the configuration of the karst conduits within an aquifer system, as well as its transmissivity and volume.
Why is hydrograph important in engineering hydrology?
The hydrograph is important for feeding in data on the potenital magnitude and frequency of floods. They are therefore a vital means to managing rivers and drainage basins. In the hydrograph above we can see that discharge increases rapidly due to a period of extended rainfall.
Why is a hydrograph useful?
How do human activities affect hydrographs?
Human Factors Affecting Storm Hydrographs Area that have been urbanised result in an in crease in the use of impermeable building materials. This means infiltration levels decrease and surface runnoff increases. This leads to a short lag time and an increase in peak discharge.
Why is a hydrograph very important in engineering hydrology?
What factors affect hydrograph?
Let’s take a look at these different flood hydrograph dynamics.
- Shape. A circular shaped drainage basin leads to rapid drainage whereas a long drainage basin will take time for the water to reach the river.
- Topography & relief.
- Heavy Storms.
- Lengthy rainfall.
- Snowfall.
- Vegetation.
- Rock type.
Why do we construct hydrographs?
CONSTRUCTION OF UNIT HYDROGRAPH. The unit hydrograph method is use for determination of the maximum flood discharge of a stream and also for developing a flood hydrograph corresponding to any anticipated rainfall.
What factors influence storm hydrographs?
Factors Affecting a Storm Hydrograph
- The Drainage Basin. The shape of a hydrograph is altered by a few different things.
- Soil & Rock Type.
- Weather & Climate.
- Vegetation Cover.
- Human Activity.