With a view to meeting growing food and fiber needs there is urgent need to create additional water storage capacity to make up for the loss of live storage in existing reservoirs due to silting.
This was suggested by Punjab Economic Report 2007, which was released recently. It was projected in the report that live storage capacity of the three main reservoirs located in Punjab, namely Mangla, Terbela and Chashma, would decrease by 5.1 MAF (33.12 percent) by 2025 from its original design capacity of 15.6 MAF. The deposition of silt is cause for the loss on the live storage capacity.
Discussing the issues with agriculture-water, the report says present canal water supplies are inadequate for meeting the requirements of the agriculture sector. Without increasing agricultural productivity, it might not be possible to meet the food and fiber needs of a growing economy.
Water productivity is low in Punjab. This is due to low yields per acre of crops and low irrigation efficiency. For example, yields of wheat in Pakistani Punjab are roughly half those of India per unit of land and this ratio is 5:8 per unit of water.
Irrigation efficiency in Pakistan is only around 40 percent, largely because farmers use traditional flood irrigation on inadequately levelled fields. Water-efficient methods of irrigation, especially for field preparation, such as making furrows, laser land levelling and precision land levelling, are adopted on only a limited scale. Integrating water-conserving, low-pressurised irrigation technologies into the existing gravity flow irrigation system represents a challenge for the agricultural research and extension system.
The report termed inappropriate crop mix and unsustainable ground water usage as some other issues faced by the sector. While suggesting ways and means to tackle these problems, the report stressed the need for creating additional water storage capacity urgently and ensuring the physical sustainability of irrigation infrastructure through future budgetary allocations for clearing the backlog of deferred maintenance. Financial space should be created, among other things, by the accelerated transition of SCARP tube wells to help provide resources for irrigation system rehabilitation and modernisation. To cope with the increased demands being placed on the irrigation system, constraints imposed by design intensities should be alleviated by remodelling/redesigning barrages, canals, and other water infrastructure, the report added.
The productivity of crops should be increased to ensure higher returns from water used for irrigation. Drought-resistant and salt-tolerant varieties of crops should be developed. Moreover, agricultural extension services should include water extension to encourage farmers to adopt improved irrigation practices and methods.
While considerable scope exists for improving water productivity by enhancing yields of traditional crops, efforts should be made to encourage a shift to high-value, non-traditional agricultural enterprises (fruits, tunnel vegetable farming, flowers, fisheries, etc). Water-conserving cropping patterns should be adopted. Sugarcane water requirements are very high; its area should not be expanded and should be curtailed if possible. On the other hand, there is scope for enhancing livestock productivity by increasing fodder production.
Irrigation efficiency should be viewed from a basin Perspective rather than focusing exclusively on field or farm-level efficiency. Many water conservation technologies (drip, sprinkler systems, lining water channels, etc) that save water by reducing percolation losses do not save much water from a basin Perspective. These systems, however, are appealing because they can ensure water adequacy at farm level, enhancing productivity by effectively using water during critical stages, and saving on some of the energy costs incurred when pumping from deep aquifers. Investment decisions regarding these systems should be based on the above-mentioned benefits rather than farm-level water savings.
Equity in surface water irrigation system should be improved as a means of enhancing productivity and alleviating poverty. Leverage for achievement of equity objectives can be gained from the participatory management of irrigation system being undertaken in some parts of the system.
Canal water allowance should be rationalised with a view to enhancing agricultural productivity and ensuring the sustainability of the land resource base. Because irrigation now takes place in a truly conjunctive-use environment, surface water allocation should also be geared toward recharge management. Groundwater use should be regulated in co-operation with CBOs (eg, those being set up under the Punjab Irrigation and Drainage Authority [PIDA]) to prevent seriously unsustainable levels of abstractions. Special efforts should be made to check the uncontrolled mining of freshwater lenses overlying aquifers in SGW zones.
Investments in drainage should be made to ensure that agricultural productivity does not decline due to water logging and salinity. The Government of Punjab should set up a water resources monitoring program to monitor surface and groundwater quality, keep track of spatial patterns in groundwater abstraction, and make all the above information available on a timely basis for policy decisions.
The organisational structure of water resources monitoring needs to be streamlined and awareness-raising efforts should be strengthened to disseminate water resource information to the public, create an understanding of water resource issues, and build support for water resource management options. Comprehensive water resource management plans, should be prepared at doaba or canal command levels, the report said.
Flood early warning systems should be created and adequate financial allocations made for regular maintenance and rehabilitation of flood protection infrastructure. Moreover, plans should be made to harness floodwater to augment surface water supplies, the report said and also called for farmers participation in all these efforts.