Difficult in understanding concept of hydroghaphy

(1e) Hydrograph A hydrograph is a graph showing changes in the as discharge of a river over a period of time. it can also refer to a graph showing the volume of water reaching flts a particular outfall, or locationin a sewerage network, am related to time. Hydrographs are commonly used in SS the design of sewerage, more specifically, the design of surface water sewerage systems and combined Systems. Factors Affecting The Hydrograph Soil Saturation is dependant on previous rainfall, or otherwise known as Antecedent rainfall. The surroundings; Rural or Urban (Could be less impermeable surface, or the surface type could vary). Vegetation type (Deforestation and amount of interception). Steepness of surrounding land, or 'relief land. Drainage density (Number of tributaries) Geology (Rock Type; impermeable = flashier hydrographs. Or Permeable) Season dependant; Very dry weather creates a crust on the river bed. Wet winters create increase in discharge. Soil Type (Clay, sand etc.) Clay would create a flashy hydrograph, but there could be aa continium between the two. Shape of drainage basin (circular or elongated). Precipitation (distribution of rainfall rates and locations) Surface Water Hydrography In surface water hydrology, a hydrograph is a time record of the discharge of a stream, river or watershed outlet. Rainfall is typically the main input to a watershed and the streamflow is often considered the output of the watershed; a hydrograph is a representation of how a watershed responds to rainfall. They are used in hydrology and water resources planning. A watersheds response to rainfall depends on a variety of factors which affect the shape of a hydrograph Watershed topography and geology (i.e. bedrock permeability) The area of a basin receiving rainfall. Land-use (e.g. agriculture, urban development, forestry operations) Drainage density Toll Free 1800-1201021 799