Rapid and often haphazard economic development and population growth coupled with climate change threaten to push the region – specifically the most needy and vulnerable among its inhabitants – into a vicious cycle of droughts and floods, of water that is unfit to drink, and a range of environmental hazards.

Water security, as outlined in the recently releasedHindu Kush Himalaya Assessment, is “the capacity of HKH populations to safeguard sustainable access to adequate quantities of acceptable quality water for resilient societies and ecosystems, to ensure protection against water-borne pollution and water-related disasters, and to adapt to uncertain global change – in a regional climate of peace and political stability.”The findings of the assessment, the result of three years of research and policy engagement by hundreds of international experts and national- and local-level decision makers in the region, show that achieving this goal will require sound planning, regional cooperation, and science-based policy making.

As the authors of the Water chapter of the HKH Assessment, we turn to the region’s governments and societies and make a renewed, urgent call to action:

·      To counter the formidable and immediate threats to water security posed by human drivers and climate change, equitable, productive, and sustainable water use should be promoted through decentralized decision making, effective management of urban pollution, improved infrastructure planning, and enhanced regional cooperation.

·      Ensuring regional and local water security requires proactive HKH-wide cooperation, specifically in open data sharing among scientists and governments; conflict management via regional platforms; and investment of public- and private-sector funds for generating and exchanging knowledge, enhancing public awareness, and stimulating action.

·      Trade-offs between upstream and downstream water uses; between rural and urban areas; and among irrigation, energy, industrial, and other sectors must be carefully managed in order to enhance water security.
 
The current state of scientific knowledge
Climate change impacts are already upon us; we must adapt even as we try to mitigate.

The HKH mountains are the source of 10 major Asian rivers, which provide water and support food and energy production, and a range of other ecosystem services in the continent. The principal sources of water in the region are precipitation, glacial melt, snow melt, runoff, river discharge, springs, and groundwater.

Groundwater, from springs in the mid-hills of the HKH, is an important contributor to river base flow. The contribution of springs to overall water budgets in the region is poorly understood. We urgently need better scientific knowledge of groundwater in the HKH, especially because millions of mountain people depend directly on springs.

And while glacier and snow melt are important components of overall streamflow in the region, rainfall runoff contributes the largest share of streamflow in the eastern rivers. As a result of climate change, a consistent increase in streamflow is expected at large scales for the upstream reaches of the Indus, Ganges, and Brahmaputra rivers until at least 2050. In the Indus, this increase will result from increased glacial melt for a limited period, while in the Ganges and the Brahmaputra, it is expected to result mainly from increased precipitation. Pre-monsoon flows are expected to decline, with implications for irrigation, hydropower, and ecosystem services.

Natural flow regimes and benefits for mountain communities must be considered for the development of the region’s hydropower potential to be sustainable. As hydropower projects can change the timing and location of river flow, they disrupt natural flow regimes, which can impact other water users and needs, such as local irrigation, capture fisheries, and ecosystems. Appropriate mitigation measures and benefit-sharing norms are needed to ensure that mountains and mountain people benefit from the region’s vast hydropower potential totalling 500 gigawatts.
 
Water security in the Hindu Kush Himalaya
Good water governance, politically and culturally tailored to the local, national, and regional contexts, is needed to ensure water security in the HKH. 

Unequal power dynamics, centralized decision making, and inadequate opportunities for local communities to influence their water-security decisions despite the presence of local institutions are among the leading causes of poor water governance in the HKH. These are all taking place under constantly changing conditions in an ecologically fragile landscape with dispersed settlements.

Decision-making must account for prevailing approaches to water governance in the region, characterized by hybrid formal-informal regimes with a prevalence of informal institutions at the local level and formal state institutions at national and regional levels. While the absence of institutions working on transboundary water resources in the region does presents opportunities for HKH-wide cooperation, it is important to note that the risks of water-related conflict are high.

More attention needs to be paid to HKH-specific conditions. Participatory and cooperative decision making, evidence-based policies, transparent programme implementation, accountability at all levels, and transboundary and regional cooperation are essential to ensuring water security in the region.

(Aditi Mukherji is a Consultant with International Water Management Institute, Sri Lanka,  Fan Zhang, Chinese Academy of Sciences, China and  Christopher Scott, University of Arizona, USA)