Water scarcity — myth or reality?
THE debate on this country’s water security, now being spearheaded by the Honourable Chief Justice of Pakistan, is finding traction with a wide range of stakeholders.
The need for enhancing storage capacity through construction of large dams is being propagated vigorously by policymakers, and receiving positive affirmation from the public. However, there are concerns based on geo-technical surveys that need to be taken into account as we proceed with mega dam projects.
Some voices have raised alarm about the phenomena of reservoir-induced seismicity. Not many people are familiar with the term, but RIS represents three timescales of seismicity which include: (i) initial loading from water and increased pore pressure, (ii) delayed diffusion of pore pressure, and (iii) protracted subsequent changes in water level.
The measured hydraulic diffusivity from induced earthquakes is the result of changes in elastic stress and pore pressure called seismogenic permeability.
According to studies conducted by the Geological Survey of Pakistan, the site for the Diamer-Bhasha dam is traversed by multiple fault lines and lies at the plate boundary between the Indian and Eurasian plates.
The second concern, according to water expert Daanish Mustafa, is that the Indus River has one of the highest silt loads in the world, and building one of the world’s highest concrete-filled dams at such a site entails the risk of triggering a massive earthquake.
Pakistan needs to explore sustainable solutions that are good for people and the environment.
The third compelling consideration is about the question of scarcity itself. Is Pakistan really water scarce, or is the dwindling per capita availability of water due more to the steady unsustainable increase in population and mismanagement of present flows? According to William Young, the lead water management specialist at the World Bank, there are five persistent myths that are barriers to improving water security that can end up misguiding policy. The following is a summary:
First: Pakistan is a water rich country and needs to shift its focus from scarcity to managing water demand, and producing more from each drop. Only 35 countries in the world have more renewable water than Pakistan, and there are 32 countries that have less water per person, and most are much wealthier and use less water for each person, than Pakistan.
Second: Storage is used to buffer the variability of flows to match the time varying pattern of demand. The Indus flows do not vary greatly, making the need for reservoir storage from one year to the next unnecessary. Storage needed to even out within-year variations associated with the monsoons can be done more cost effectively by run-of-the-river facilities. Justifying the cost of large dams is difficult given our irrigation inefficiencies and the high sediment accumulation rate in reservoirs.
Third: Although climate change appears to be affecting rainfall, snowfall and glacial melt, it has no clear trends, and no significant changes in river flows are projected before 2050. While a 20-28 per cent ice volume reduction is anticipated (mostly at lower elevations), since the Indus has a greater share of glacial ice at higher elevations, the faster rates of warming do not support absolute higher temperature projections to drive rapid melting there.
Fourth: It is estimated that irrigation at the basin-scale is over 80pc efficient. The proportion of irrigation water lost due to evaporation and non-productive plant use is minimal compared to losses through drainage returns to the river and seepage to groundwater. Irrigations problems are more about inefficient and unfair water distribution, and low productivity in terms of the yield and value of crops per unit of water.
Fifth: The flows to the sea are commonly seen as wastage, and average annual flow reduced by more than 80pc. There is strong evidence that declining flows have a significant effect on accelerating the decline in health of the lower river and delta, and in destabilising these vital ecosystems.
To address Pakistan’s water woes, it needs to take all the above mentioned concerns into account in order to develop sustainable solutions. The political economy of water makes it increasingly difficult to tackle water in a country that is divided along ethnic and provincial lines, and has a relationship of distrust with the two upper trans-boundary riparian countries. That is perhaps one reason why even the newly approved National Water Policy assiduously avoids mention of the word ‘dam’ in its 33 stated policy objectives and only talks about the need for building storage capacity.
As the policy instruments to support the objectives have yet to be developed, it would be desirable if the government engages with all stakeholders in a participatory and inclusive manner to discuss and assess all forms of storage and not just large dams. Small storages throughout the distribution network may enable highly valuable re-regulation of flows. There is need for enhanced control to match field-scale water supply to water demand.
The role of the provinces after the passage of the 18th Amendment will be critical in achieving the core objectives of the policy, and a collaborative approach that brings together all actors, including civil society, to co-create recommendations for its implementation framework will go a long way in building and cementing cohesion.
The moot point is that while infrastructure and technology will remain an integral part of ensuring water security, it is political and governance issues that will end up being the most complex barriers to finding solutions that are acceptable to all stakeholders. A science policy dialogue — based on assessments of water sources, flow patterns and storage, and usage and distribution — is vital for reaching an agreement that is fair and equitable, as well as safe and sustainable, by bringing all parties on board to develop an actionable roadmap for making Pakistan water secure.
The writer is chief executive of the Civil Society Coalition for Climate Change.
aisha@csccc.org.pk
Published in Dawn, October 13th, 2018