How to Determine the Frequency of Irrigation Mathematical Problem The following data are given to determine the frequency of irrigation Field capacity of soil = 45 % Permanent wilting point = 19 % Density of soil = 1.5 g/cm3 Depth of root zone = 65 cm Daily consumptive use of water = 18 mm Solution: … Continue reading How to Determine the Frequency of Irrigation – Problem & Solution →

Find the intensity of Rainfall When the duration of Rainfall is Given First of all, we need to know the formula used to determine rainfall intensity. There are three types of empirical formulas - a) For storm duration of 5 to 20 minutes b) For storm duration of 20 to 100 minutes c) Where rainfall … Continue reading Find the Intensity of Rainfall When the duration of Rainfall is Given →

How to Determine Runoff by using Rational Method First of all, we need to understand which formula or expression is used for the determination of runoff. In the rational method, the runoff is given by the following expression: Where, Q = Runoff in cumecK = Coefficient of runoffi = Intensity of rainfall in cm/hrA = … Continue reading How to Determine Runoff by using Rational Method – Mathematical Problem & Solution →

How to Determine Runoff Coefficient When the nature of the surface of different areas and the impermeability factors of the areas are known or given, then the value of the runoff coefficient(K) may be determined by the following expression: Where,  a1, a2 = Area of different surfaces.p1, p2 = Impermeability factors of those surfaces.A = Total surface … Continue reading How to Determine Runoff Coefficient – Mathematical Problem & Solution →