Groundwater depletion in the Indus Plains of Pakistan: imperatives, repercussions and management issues

ABSTRACT

The sustainability of agricultural growth has been greatly influenced by the massive use of groundwater in Pakistan for the last few decades. However, the groundwater economy of Pakistan is at critical juncture now. Concomitant with massive pumping of groundwater aquifers through unrestricted expansion of tube-wells, groundwater exploitation has led to many negative environmental, economic and spatial impacts and serious threats to the sustainability of irrigated agriculture in the region. The spectacular increase in the groundwater development during the last half-century has manifested as a kind of ‘silent revolution’ carried out by thousands of farmers in pursuit of reliable irrigation water supplies. The groundwater revolution in the Indus Basin has been a result of a succession of factors –each of them exacerbated the groundwater crises in the subsequent periods. Massive groundwater extraction programmes were commenced to overcome waterlogging and salinity, which was blown up by large-scale surface water developments in coming years. Within this backdrop, this article attempts to identify the causes and consequences of groundwater overdrafting in Pakistan and draws attention to groundwater resource management issues. In this article, we discuss how the rigidity of the surface-water-allocation system, the Green Revolution, the Indus Water Treaty, soaring population and the groundwater management policies have led to groundwater revolution. Major environmental impacts identified include soil salinization, salt water and sea water intrusion, land subsidence, and drying up of lakes and vegetation in different parts of the country. Various pecuniary impacts such as increasing pumping costs while decreasing land values are also very prominent. Migration and prospective social conflicts are amongst the potential spatial impacts. We have concluded that decreasing surface water supplies, unimpeded pumping of aquifers, lack of groundwater entitlements and the institutional impediments are the major problems related to the sustainable groundwater management in Pakistan.

KEYWORDS:

• Groundwater overdrafting
• groundwater development
• tube-wells
• groundwater irrigation
• Indus Basin
• Pakistan

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

1. Karez is an underground tunnel that is constructed to collect subsoil water through the gravitational pull at the foot of hills. This water is then diverted towards fields or villages either for irrigation or domestic needs.

2. Warabandi system distributes the canal water supplies equitably proportional to the farm size as a fixed weekly rotation.

3. The notion ‘protective irrigation’ means to design and operate an irrigation system based on the principle that the available water should be spread equitably in order to cover as many farmers as possible without taking into consideration the full crop water requirements Jurriens et al. (1996).

4. There are two cropping seasons in Pakistan, Kharif and Rabi. Kharif starts from June, July and goes to October, November, while the Rabi season starts from September, October and continues to April, May. However, cropping time varies geographically across the country.