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The total area of Pakistan is 796101 sq. km (310,400 sq. miles) of which 414659 sq. km (160100 sq. miles) comprises mountainous terrain, narrow valleys and foot hills. The remaining 381442 sq. km (150300 sq. miles) consists of sand, deserts and flat gradational plains, the most important feature of which is Indus River Basin Plain with an area of about 311771 sq. km (123400 sq. miles). The area of principal hydrologic units is given in Table 1.

Pakistan has waged a struggle of near epic dimensions for the control of waterlogging and salinity in the Indus Basin, a struggle which has engaged much of the country resources, greatly challenged its political commitment and is already lasting more than one hundred years. This paper records the history, the successes and failures, the ups and the downs of this struggle and ends with perspective analysis of the present status and remaining issues. Copyright © 2007 John Wiley & Sons, Ltd.

The main objective of this study was to develop a procedure to evaluate various recharge components of a groundwater reservoir to estimate the long term average seasonal groundwater recharge in Rechna doab in the Punjab province of Pakistan. A regional lumped water balance model for the Rechna doab was developed and applied to estimate the long term a seasonal recharge to groundwater reservoir. For comparison, recharge was also estimated by a specific yield method from observed groundwater levels. A water balance study was conducted on seasonal basis (6 months) for a period of 31 years (1960–1990). Recharge estimated by the two methods was found to be in good agreement. The average value of net groundwater recharge during Kharif (April–September) season was found to be some 60 mm. No recharge occurred during Rabi (October–March), rather there was a depletion of the groundwater reservoir during the winter months. Long term average annual depletion of a groundwater reservoir was found to be greater than corresponding value of annual recharge. It was concluded that on a regional basis the groundwater reservoir was being depleted resulting in an average groundwater table of Rechna doab about 2.3 m fall over the 1960–1990 period.

This study was conducted on Gugera Branch of Lower Chenab Canal, Punjab, Pakistan. Sample distributaries off taking from Gugera Branch were selected for the study. The existing conditions of water distribution among the distributaries were studied. Field data were collected during the whole of 1988. Field observations suggested that the variability at the head of distributaries is much greater than the variability in the Gugera Branch under existing operational practices. The distribution of water among the distributaries is rarely in accordance with design criteria. Some channels get priority over other channels. The annual closure period varied from 17 to 41 days for different channels. The discharge at the head of distributaries remained lower than the standard operational range for 69 to 183 days in a year. The data suggested that a regulating gate at the head of the distributary can reduce discharge variation up to 2.4 times compared with a ‘Karrees System’ (wooden stop logs used for water regulation). The data indicated that the adjustments in the head gate of a distributary on daily basis can substantially improve discharge conditions at the head of distributary. Rotational schedules are not being followed as per design and need to be improved. Most of the existing head discharge relationships of discharge measuring structures are not reliable. A frequent calibration of these structures is recommended.