CS(AR)-2-96-97 : Estimation of infiltration rates in the Suddagedda basin, East Godavari district, A.P.

Abstract

Suddagedda basin is adopted as a representative basin of east flowing rivers of medium sized basins in the east coast of India by the Institute. The basin soil mainly grouped into clay loams to clay, sandy loams and forest and loamy skeletal. As a part of experimental studies in the basin total 28 infiltration tests have been conducted using double ring infiltrometers. Using the experimental data the average infiltration rate of the soil groups are obtained from fitted Horton's equation. The correlation coefficient between observed data and fitted Horton's equation varied between 0.83 to 0.99. The average infiltration rates in clay loams to clay, sandy loams and forest & loamy skeletal are 2.50, 3.94 and 7.12 cm/hr respectively. The highest average initial infiltration rate (39.2 cm/hr) and average final infiltration rate (4.7 cm/hr) were observed in forest & loamy skeletal soil and lowest average initial infiltration rate (19.4 cm/hr) and average final infiltration rate (1.31cm/hr) were in agricultural land. According to landuse classifications the highest average infiltration rate was obtained in Barren land (6.9 cm/hr) and lowest rate in agricultural land (2.50 cm/hr). A map showing the spatial distribution of average infiltration rates in the Suddagedda basin was prepared.