Qanat

A qanat is a water management system used to secure reliable water supply to human settlements or irrigation in semi-arid and arid regions. Probably originating in Persia, the qanat sys- tem has been adopted and developed further in large parts of Asia and Europe. Its widespread use is reflected in the many names for the system and similar systems; kariz/kahan (Per- sian), khettara (Morocco), galeria (Spain), falaj (United Arab Emirates and Oman), kahn (Baloch), foggara/fughara (North Africa), and karez (Armenia and China). A qanat consists of many well-like vertical shafts connected by a gently sloping tun- nel (Fig. 16) Tapping into the subterranean water table, the qa- nat system is effective in delivering large quantities of water to locations lower than the water source without pumping.

Qanats have played a vital role in making areas inhabitable throughout history. It is estimated that only in Iran, around 50,000 qanats have been in use. Although expensive and labor- demanding to construct, the long-term benefits of qanats were substantial for the community. Qanats are relatively immune to natural disasters and war, and are not dependent on die- sel pumps like modern wells. However, the wells and tunnels

require periodical maintenance, and much of the traditional knowledge on maintaining and constructing qanats has been lost (Lightfoot, 1996; Motiee et al. 2006).

Vertical access shafts Qanat outlet Irrigated area Qanat channel Water table Qanat

Figure 16: Cross-section of a qanat. Source: based on a ICQHS- UNESCO diagram.

age potential of glacial lakes and glacial and snowmelt water among major regions such as the Hindu Kush-Himalayas and the Andes will be of great importance.

Capacity building, investments in environmentally friendly, small-scale technology and development, and the implemen- tation of improved irrigation systems, designed to optimize the water irrigation exactly according to plant demand, reduc- ing evaporation, and reducing runoff, could likely increase ef- ficiency in water usage several-fold. It is expected that major changes and efficiency improvements in the agricultural sec- tor will take decades to implement. The time frame for imple- mentation now is probably less than a couple of decades. In order to sustain populations we need a revolution in Asia – a ‘blue revolution‘ of water efficiency.

Reviews of current adaptation strategies in mountain regions suggest several important lessons. First of all adaptation and

development must be considered a continuum. At one end are development activities such as providing drinking water, energy and food security, while at the other end are efforts required to reduce vulnerability to climate change and build resilience. Livelihood diversification is a key adaptation strat- egy, but it requires policy and institutional support. Likewise social networks and local institutions play a vital role in devel- oping adaptive capacity. Furthermore, cultural norms affect adaptive behavior, but can also shift over time in response to environmental stress. If good governance and planning takes climate change into account, infrastructure development can contribute to enhancing water security and flood manage- ment. Also policy at different levels plays a paramount part in how successfully the effects of climate change are dealt with. Policy at national and international levels often has strong implications for local conditions, but higher level poli- cies are often out of touch with local concerns and realities (ICIMOD, 2009).

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