Equity Considerations in Irrigation Design and Inequitable Distribution of Groundwater in LBDC Command

• Main Authors: Muhammad Basharat, Ata-Ur-Rehman Tariq
• Format: Article
• Language: English
• Published: Mehran University of Engineering and Technology 2012-10-01
• Series: Mehran University Research Journal of Engineering and Technology
• Subjects: Equity; Groundwater; Irrigation; Crop Water Requirement; Rationalization.
• Online Access: http://publications.muet.edu.pk/research_papers/pdf/pdf689.pdf

Climatic variability across the command of LBDC (Lower Bari Doab Canal) has pernicious impact on equitable usage of irrigation water from head to tail. The main thrust of this study is to highlight the need for rationalizing water allowance within the canal command so that joint equity of both the canal and ground water availability to the farmers is ensured. Tail reach areas receive only about 212mm annual rainfall which is 45% of the rainfall at head reach (472mm). Whereas, the crop delta increases from head to tail, with minimum difference of 13mm and maximum of 147mm for oilseeds and sugarcane crops respectively. For wheat/cotton rotation, combined annual difference in delta between tail and head reach areas comes out to be 133mm. Adding this difference in crop delta to rainfall difference (260.6mm), a total difference comes out to be 393.6mm which is 33% of field delta for wheat/cotton crop rotation at head reach of LBDC command. This difference in irrigated hydrology across the command is responsible for successively increased depth to groundwater towards tail of the command. Accordingly, the tail end farmers are forced to incur higher costs per acre for groundwater pumping. This is because groundwater pumping from deeper depths in tail areas is about 3.5 times more costly as compared to head reach. So there is dire need to ensure equitable irrigation water availability in terms of quantity and cost, rationalization of water allowance is recommended to achieve this equity.