A hydrograph is plotted to show the flow rate (rate of flow. The rate of flow refers to the discharge against the time taken. According to Štajdohar et al. ( 2016), a hydrograph indicates a plot showing the discharge (instantaneous) against time. The units used when referring to discharge, or the flow rate is either M3 (cubic meters) or cubic feet in one second. A hydrograph is critical when it comes to hydrology because one can look at the meteorological and the physiographic conditions that may be present in a particular watershed. The hydrograph is also related to factors like surface run-offs, hydrologic loss, and groundwater flow, and also interflow. It is, therefore, remarkable since it indicates how any basin may respond when it rains continuously. The hydrographs also describe how a river discharge responds to rainfall. We have several types of hydrographs, and they include:
- Bank full refers to the amount of Discharge Rivers are capable of holding when it rains before flooding.
- Slow floods- these kinds of hydrographs get created in cases where rivers flow for very long periods.
- Rapid floods- these hydrographs are made during storms when rivers take less than six hours to flood when it rains.
Hydrograph to assist when describing discharge changes in cases of urbanization
The rate of discharge increases in the case of urbanization. Factors like vegetation, drainage, and slope affect the hydrograph. Such factors change because of urbanization, and this affects how drainage takes place. A large number of impermeable surfaces characterize urban areas. They increase the rate of water run-off to the nearest drains and gutters, which direct water to the closest water sources (Štajdohar et al. 2016).
References
Štajdohar, M., Brilly, M., & Šraj, M. (2016). The influence of sustainable measures on run-off hydrograph from an urbanized drainage area. Acta hydrotechnica, 29(51), 145-162.
