Progress 

Research Findings of Completed Studies(PCII- 2009-2015)

i.Groundwater Management (Recharge Potential and Governance)

• Lower and central parts of the Bari Doab have alarming depleting rates (16 to 55 cm/year),with about 1.89 MAF/year.
• Fresh assessment of crop water requirement, cropping patterns and intensities, and existing allocations is strongly recommended.
• Re-allocating canal water for equity in relative irrigation demand rather than supply at IBIS, provincial and canal command levels is crucial.
• Controlling cropping pattern and intensities is the best option for groundwater governance in depleted areas;
• Frame a national water law for regulation of surface and groundwater at various levels;
• Maintaining groundwater levels 8-10 ft below NSL would be required to accommodate rainfall seepage and in order to  avoid rainfall flooding in Sindh;
• Assessment of optimum groundwater development potential for different areas in Lower Indus is required;
• In fresh groundwater areas, reduce canal supplies to such a level that the canal water and groundwater pumping are able to meet crop demands together, and depth to watertable (DTW) is maintained at about 8-10 ft.

   ii.Engineering Economics and Hydrology of Canal Lining

• The comparison of canal lining to that of tube well shows a payback period between four to six years. The canal lining is cost-effective only when the useful life of the improved canal exceeds eight years. Canal lining is sustainable because it not only reduces the storage requirements but also the pumping cost as well. The cost of water produced through groundwater abstraction is much higher than the water saved through canal lining.
• Water conservation via canal lining can be captured more quickly as to other options. The economic value of water saved per acre-ft as a result of canal lining is the highest and most incremental, among all known sources of conservation for irrigation water. Reduction in seepages due to lining would save precious water, which can then be used to cover additional area.
• The economic justification for canal lining program is not clear when applying multiple options of discounted rate and expected life. Critical decision factors for the justification include method of seepage estimation, irrigation water price, the true expected life and discounted factors that are to be used for the analysis.
• The economic profitability of canal lining is not very attractive and justified even if benefits are increased by 10 percent. The economic profitability could be fairly advantageous if benefits increased by 20 percent. The canal lining in saline ground water areas is feasible. It is therefore, emphasized that lining of all irrigation networks in the saline zone should be ensured.

   iii. Reuse of Saline Water for Agriculture in RBOD and LBOD Areas

• Use of drainage water may be confined to low delta crops. Continuous use of drainage effluent must be avoided. However, marginal quality effluent may be used after mixing with canal water.
• In case of sodic soil amendments like pressmud (residue of sugar mills) or farm yard manure may be used.
• Conjunctive use of drain and canal water is effective in case of highly saline water.