Estimating the Impacts of Climate Change on Sectoral Water Demand in Pakistan
September 27, 2017
BackgroundAccording to the Germanwatch Global Climate Risk Index 2017, Pakistan is rated amongst the top ten countries most vulnerable to climate change. In the last half-decade, it has experienced devastating floods almost annually, and in 2015 a heatwave in Karachi resulted in around 1200 deaths. Although this is in line with global trends, it will leave Pakistan hard pressed for water resources. The demand by various sectors will create tremendous pressure and force diversion of water from agriculture to other competing uses. As the population increases and average temperature continues to rise, there will be both spatial and time-related water shortages with surges in demand. In particular, heat-related stresses in agriculture and domestic use will require more water than normal, with an overall increase in demand as well as seasonal shifts in the water requirements of various sectors. Historically, much of the scientific data on water, globally and in Pakistan, has focused on supply and paid little attention to demand. Given that the population is rapidly increasing and climate change is likely to put pressure on existing water allocations, it is crucial for policymakers and water experts to understand demand and how to manage it. Responding to this need, LEAD Pakistan hosted an interactive session and webinar with Dr. Zaigham Habib, a hydrologist and water resources expert, and Dr. Pervaiz Amir, a senior economist, to present the findings from their study 'Estimating the impacts of climate change on sectoral water demand in Pakistan'. Sectoral demands for water: key issues and challenges Agriculture is one of Pakistan's biggest economic sectors, employing more than 40% of the population and with an estimated share of about 85% of total water usage. In most regions, agriculture is under stress due to factors such as urban expansion and groundwater depletion, though simultaneously the need to maximize production in the face of a growing population is leading to crop intensification, a shift to high-yield crops, multiple cropping and excessive land cultivation. Another shift is the phenomenal growth of the livestock, the average annual water requirement for which is projected to increase from 1.2 BCM in 2006 to 4.9 BCM in 2050. Current estimates indicate that an increase in average temperature of 2 degrees Celsius would augment the water intake of a large animal by about 4% and a 4 degree increase would do so by 10%. With a rising population, the net availability of water has dropped from 5000 cubic meters per person per year in 1951 to the current level of about 1100 cubic meters. Given that water demand is closely linked with population growth, related trends and projections can help to determine water allocation policy. For Pakistan, there are three potential population growth scenarios post-2015. The average growth rate in these scenarios ranges from 1.58% to 2.1%. This is expected to decline to 0.5% by 2050 (though the population will still be over 300 million). However, even if the growth rate declines, the lack of water available for drinking and domestic use remains an issue in both urban and rural areas due to below par water quality for direct human consumption. This poses a massive challenge since it is expected that 60% of Pakistan's population will be based in urban or peri-urban areas by 2035. To compensate for the lack of clean surface water, unregulated extraction of groundwater has become a common practice. While it can provide short-term water security, it is leading to depletion of the water table and will ultimately make living in most cities and urban centers unsustainable (as is the case, to varying degrees, in Karachi, Quetta and Lahore). Still, generally speaking, outside of the agriculture sector, there is a lack of reliable data on the uses of water in Pakistan. As a result, most of it is underestimated or not accounted for. Moreover, demand is generally confused with supply side efficiency, while new water allocations need to be made in accordance with various development plans and agendas. Similarly, there is a high degree of uncertainty in climate change projections that means the impact of climate change on sectoral water demand requires further research and analysis. The outlook for Pakistan, recommendations and way forward Despite climate change and the pressure of population growth, Pakistan is not a water-stressed country. Similarly, contrary to popular belief, Pakistan does in fact have an informal water market, but it needs to be based on demand. For instance, in Punjab, which is the most populous province, lack of water pricing is resulting in excessive wastage. Meanwhile, in Sindh, improper water pricing is a major cause of the water crisis, which according to the researchers is mostly man-made. According to the researchers, the most pressing policy concerns for meeting sectoral water demand in Pakistan are:
- The quality of drinking water
- Rationalizing the share of water in agriculture
- Equitable and sustainable distribution/sharing of total water benefits amongst the provinces
- Water needs to be diverted from agriculture and spread equitably across other sectors, but taking from agriculture could create massive conflicts.
- Climate change is a major variable that impacts sectoral water demand and presents a 'time and space' problem for both demand and supply.
- As the temperature increases, water demand - especially for domestic and industrial use - will also go up.
- Water security should be seen as being as critical as national security because of its importance to humans and ecosystems.
- Aside from demand, adequate attention must be given to the quality of water.
- A strong government subsidy is needed to ensure that everyone has the right to safe drinking water. However, for other uses, we need to have proper, regulated water pricing.
- In terms of policy and planning, more needs to be done at the provincial and district levels.