Effect of crop water intake on water table depth: A case study of Chanchaga irrigation scheme

Abstract

A study to determine crop water intake, on water table depth at the Chanchaga irrigation scheme was carried out by identifying and monitoring water table depth fluctuations. Three piezometric pipes were installed within the study area at varying distances apart to monitor the three wells (A, B and C). Infiltration rate tests were also carried out to determine the rate at which water infiltrates into the various types of soil in the study area. The water level was determined twice within a month during the months of January to May to determine their level of fluctuations. Soil physical properties such as moisture content, bulk density, porosity, available soil moisture holding capacity and the infiltration rate of the soil were investigated within the study area. The groundwater fluctuation at the project site shows that the water level in wells B and C were within the active root zone depth of shallow rooted and moderate rooted crops. The water level in the three wells indicates that areas surrounding wells should be drained only during August and September. This is to reduce the water logging effect at that period or, high water requiring crops like rice and sugarcane should be grown around well A. Around wells B and C, irrigation is needed slightly for October and entirely for the rest of the dry season.