Factors Affecting the Quantity Of Storm Sewage
The quantity of storm sewage (i.e. stormwater) is mainly affected by the following factors:
l) Shape And Size of The Catchment Ares
Stormwater(runoff )will be more for the large and fan-shaped catchment area. On the other hand, the runoff will be less for the small and ferm-shaped catchment areas.
2) Topography
Stormwater increases with the increase in the ground slope of the catchment area and vice versa.
3) Character of The Catchment Area
If the surface of the catchment area is rocky or compact clayey type, stormwater will be more. Again, if the surface of the catchment area is sandy, the stormwater will be low.
4) The direction of the prevailing storm
If the direction of the storm is the same as the direction of movement of water, the stormwater will be more and vice versa.
5) Type of Precipitation
If the precipitation occurs in the form of rain, it will produce stormwater immediately. On the other hand, if the precipitation occurs in the form of snow, it will produce stormwater at a slow rate.
6) Rainfall Distribution
The stormwater from a basin is very much dependent upon the rainfall distribution.
7) Intensity and Duration of Rainfall
The stormwater increases with the increase in the intensity of rainfall and vice versa. If the duration of rainfall is more, the stormwater will also be prolonged.
8) Soil moisture Deficiency
The runoff depends upon the soil moisture present at the time of the rainfall. If rain occurs after a long dry period, the soil will absorb huge amounts of water and thus runoff will be less. But the runoff will be more if rain occurs after a long rainy season.
9) Climatic Condition
If the temperature in the catchment area is high, the evaporation loss will be more and hence the stormwater will be less and vice versa.
10) Geological Condition of The Catchment
If the catchment area consists of fissures, cracks, etc, the water losses will be more and the stormwater will be low.
11) Vegetative Cover
The presence of a dense vegetative cover over soil increases the infiltration and thereby reduces the stormwater.
Read Also:
Factors Affecting The Quantity Of Sanitary Sewage
Determination of Quantity of Sanitary Sewage
What is Sanitary & Storm Sewage, Dry And Wet Weather Flow