Groundwater decline in Central Punjab - Is it a warning?

Abstract

Central Punjab covers around 40% area of state Punjab. Paddy covers nearly 75% of the total cropped area and requires nearly 800–2000 mm of irrigation water depending upon climate and soil type. The increase in irrigation demand has led to over-exploitation of groundwater in Central Punjab. This study aims to investigate the precipitation, temperature, groundwater and potential evapotranspiration (PET) trends in Central Punjab through an examination of historical climate data covering the past almost twenty years. This study also compared all the contributing factors of groundwater depth decline from 1998 to 2017. In years, when rainfall was above normal in 2008 and 2011, the groundwater depth decline reduced as compared to other years. The maximum (2026 mm) and minimum (1566 mm) PET was observed in 2009 and 2004. Minimum rainfall (422.6 mm) was observed in 2000 and maximum (1012 mm) was observed in 2011. Groundwater Depth was significantly positively associated with paddy area and tubewell density. Fluctuation in groundwater depth is not only due to the variability of annual rainfall but also due to paddy cultivation. Thus, there is a need for wise water management and crop diversification in this study area.