Improving groundwater management to enhance agriculture and farming livelihoods in Pakistan: Groundwater model for the Lower Bari Doab Canal, Punjab, Pakistan

Groundwater (GW) is considered as one of the most important but scarce natural resources in many arid and semi-arid regions of the world. GW contributes around 55% of the crop water requirements globally. Under changing climate, increased over extraction of GW for irrigation is considered as the main threat for coping with surface water scarcity. Many studies globally have reported that GW extraction is exceeding GW recharge for large areas, which over time causes persistent GW depletion. A comprehensive knowledge on inflows and outflows from the aquifer is prerequisite for sustainable GW management and policy. The districts of Okara and Sahiwal in the Lower Bari Doab (LBDC) Canal command area, selected for this modelling study, are situated in the Punjab province of Pakistan. The LBDC is a major part of the larger Indus River Irrigation System in Pakistan, and provides an example of an area facing irrigation and drainage issues including reduced surface water supplies. Farmers there rely on groundwater as a safety net to meet crop water requirements, but its use also leads to declining groundwater levels, and deteriorating soil health from using poor quality groundwater. The model covers an area of 0.78 million ha of irrigated land. The present irrigation system in the Lower Bari Doab consists of 2,264 km of distributaries, 201 km of main canals and 95 km of link canals, and over 60,000 tubewells which are installed in the freshwater areas.