Detection and delineation of waterlogging by remote sensing techniques

Abstract

The execution of irrigation projects without the provision of adequate drainage system has disrupted the equilibrium between the ground water recharge and discharge resulting in accretions to the ground water table in the command areas in India. The Tawa command area faces the problem of water logging resulting from over irrigation and seepage from canal system. The study was undertaken to delineate water logged areas in the Tawa command using IRS-1 A-LISS-I dala. Land use and drainage maps for the Tawa command were also prepared using IRS-1A-LISS-I, FCC of November 20. 1989 and March 23. 1989. IRS-LISS-I digital data (CCT’ s) of May 19, 1988, October 20. 1988 and November 20, 1989 was analysed to delineate areas affected by water logging and the areas sensitive to water logging. An attempt has been made to validate the IRS derived water logged area with the available water table depth data. Density slicing was found to be useful digital technique for the delineation of water logged areas. The results indicate that in October 1988 an area of 80 km2 was affected by water logging and about 140 km2 area was sensitive for water logging, where the water table was between 0 and 3 metre. It is suggested that an assessment of water logging using remotely sensed data should be carried out at regular intervals.