Groundwater Management in Pakistan, by Dr Asad Sarwar Qureshi, IWMI Pakistan
Groundwater Management in Pakistan Dr. Asad Sarwar Qureshi IWMI-PakistanGWP/IWMI Workshop on Climate Change, foodand water security, Feb. 24-25, Colombo
Why GW is so important? Existing water usage in Pakistan (BCM) Description of Uses Rainfall River Groundwater Harvesting TotalIrrigated Agriculture 76.5 51.8 5.79 134.1Domestic Water Supplies 2.59 4.19 0.37 7.15& SanitationIndustries 0.74 1.97 - 2.71 Total : 79.8 57.9 6.17 144Over 1.2 million pumps, out of which 0.8 M are only in Punjab.Increased yields by 150-200%. Cropping intensity increasesfrom 70% to 150%. Drought mitigation, Drinking water formajor cities. Major source for drinking water in urban areas.
Groundwater-poverty relationship WET Time Dimension YEAR S Comfortable Relatively Safer Zone Zone Head Middle Tail Rain-fed A Vulnerable Relatively Safer Zone Zone GW-source for survival DRY
Challenges of GW management• Over-exploitation in many areas.• Quality deterioration.• Secondary salinization• Non compliance of governing laws.
Imbalance in recharge-discharge (Water table decline in 43 canal commands) Punjab SindhThe situation in Balochistan is even worse. Sindh isextracting less groundwater due to quality concerns
Depletion due to overdraftIncreased WT depths and pumping costs. Average WT decline in the IBis 1.5 m/yr. About 5% area in Punjab and 15% in Balochistan has goneout of reach of the poor. 1993 2003
Spatial and Temporal GW Quality 1977 2003 Fresh Marginal Hazardous22% in Punjab and 78% area in Sindh has saline GW.
Soil salinization-still the biggest threatOne ton of salts per ha per year with surface water irrigation.GW irrigation and Conjunctive water use is even adding more.
GW Governance: HOW?• In addition to administrative problems, less respect for law and political interference are major reasons.• Failure of permit system (1980s).• Non implementation of GW regulatory framework in 1990s (developed with the assistance of WB) due to lack of political interest.• Failure to enforce PIDA act of 1999-2000 due to administrative and political complications.
GW management options for Pakistan• Improve surface supplies-reduce system losses.• Build storages to save water for dry periods.• Energy-groundwater nexus??? May be not for Pakistan.• Control demand to reduce dependence on GW.• GW is complex in Pakistan—No single solution.
Annual Flows to SeaDrastic reduction-threat to coastal Environment
Increase storage capacity(15% of the river flow; only enough for 30 days- 32% will be lost by 2025) 59% of the flow in the Indus comes from rainfall and 85% is received in during monsoon – storage must!!
Improve water allocation delivery and distribution-reduce system losses Description of Losses Annual System Losses (billion m3) 1975-80 1980-85 1985-90 1990-95 Canal Conveyance losses 27.4 27.3 26.9 27.0 Watercourse Conveyance Losses 41.3 41.1 40.4 40.7 Field Application Losses 15.5 15.4 15.2 15.3 Total Losses 84.2 83.8 82.5 83.0 Total Canal Diversions 130.7 130.0 128.0 128.8 Overall Irrigation Efficiency (%) 36 36 36 36 (Source: Ahmad, 2008)• Less and unreliable canal water supplies• Tail-end farmers get 20% less from middle farmers and middle farmers get 20% less than head farmers.
Electricity restrictions-not for PK• Electric wells have reduced to 10% of the total. Use of power supply as a tool for GW management is probably not the answer.• Cost of GW irrigation 30 times higher than that of surface irrigation. US$ 5.5/ha/yr for canal and 167 US$/ha/yr.• Cost of water from diesel tubewells (US ¢ 2.50/m3) is three times higher than electric tubewells (US ¢ 0.80/m3).• Farmer prefer diesel tubewells due to low initial installation costs, suitability for small fragmented farms and no worry of power cuts.• Control demand
GW management options• Rationalizing cropping patterns according to water availability (rice, sugarcane areas can be reduced??).• Improve productivity of rain-fed areas (rain-fed areas contribute only 10% of total production; Yields are only 1-1.5 t/ha and can be doubled by better WM).• Increasing use of alternate water resources (wastewater, saline water) for agriculture (Pakistan produces 4.5 BCM WW—mostly wasted).
Thank youQureshi, A.S., P.G. McCornick, A. Sarwar and B. R. Sharma, 2010. Challenges and prospectsfor sustainable groundwater management in the Indus Basin, Pakistan. Water ResourcesManagement, Vol. 24, No. 8:1551-1569.