Econometric estimation of groundwater irrigation efficiency of cotton cultivation farms in Pakistan

Study region: Lodhran and Jhang districts in the Central and South Punjab
province of Pakistan.
Study focus: Pakistan is amongst the largest groundwater withdrawing
countries. With 5.2 million hectares groundwater irrigated area, Pakistan irrigates 4.6% of the global groundwater-fed cropland. However, over the last
few decades the groundwater resources are under immense pressure due to
overdrafting to meet escalating irrigation water demands. Since most of the
groundwater is being extracted for irrigation purposes, examining irrigation
water efficiency have become has become inevitable for sustainable groundwater
management. This study estimates farm level technical efficiency (TE) and
irrigation water-use efficiency (IWE) of groundwater irrigated cotton farms in
the Punjab province of Pakistan.
New hydrological insights for the region: Irrigation water-use efficiency (IWE)
is generally defined from three perspectives: (i) efficiency of the irrigation system, i.e., water conveyance efficiency; (ii) efficiency in water application at the
farm gate and; (iii) the response of a crop to irrigation water application, i.e., the
amount of water actually utilized by the crop compared to the amount of water
supplied to that crop. These measures of IWE are devoid of economic principles.
Hence, irrigation water efficiency has expanded its boundaries from hydrological
and engineering principles to economic rationale which is useful to guide
targeted farms to improve their irrigation efficiencies. This study advances the
frontier of existing economic measure of IWE by employing a restricted production frontier model.