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UNESCO G-WADI Workshop on Water Harvesting (cont.)
Workshop Report  |  Papers & Presentations |  Case & Regional Studies |  Participants

Session 1: Historical and Traditional Perspectives

Dr. Samsar Yazdi, Director UNESCO ICQHS Yazd gave a fascinating presentation on the endeavours carried out in accordance with qanat technology and historic hydraulic structures in Iran. The vital role qanats played as a stimulus for human societies whose survival was dependant on these systems was portrayed by examples given from Iran, Oman and Afghanisitan. A total of 34355 qanats were identified in Iran and are reputed to give a total discharge of 8,212 billion m3.

He outlined how qanats had fared through the history of Persia from their founding in 714BC, with periods of decline, abandonment and reinstatement. The qanats are recognised invaluable historical legacies and yet it has been questioned how such qanats can be reinvigorated or rehabilitated. Major difficulties in their rehabilitation in Iran are due to the overexploitation and falling down of the water table. Therefore out of 609 basins a mere 220 have been defined as restricted areas. under water exploitation supervision and where the blockage of unauthorised wells actually takes place.

In May 2000 city of Yazd situated in centre of Iran hosted an International conference on Qanat under the auspices of UNESCO. At this conference the idea of the establishment of an International Centre on Qanat was put forward and was stipulated at another conference on Qanat held in 2002 in Oman. The IR of Iran's proposal concerning the establishment of the International Centre on Qanat met with UNESCO's approval in 2003. in March 2005 the agreement of the establishment and operation of the centre was signed between IR of Iran and UNESCO. The purpose of the centre is to maintain and restore such historical structures as well as the transfer of know how, experiences and traditional knowledge related to Qanat.

In the future the ICQHS plans to determine the budget required and finalise joint research projects with various centres. The transmission of knowledge has always been a priority of this organisation and thus the erection of a data bank is deemed to be essential. The compilation of the first history of Qanats is one step further in the direction of knowledge dissemination.

Conclusions from discussions
The discussion that emerged after this presentation rotated around the question of how societies can relate to the qanat system for rainwater harvesting. It was noted that today several artificial dams have been constructed upstream of qanats, This has aided the discharge of qanats and is a clear example of modern soft engineering technologies involving rainwater harvesting enhancing qanat technology.

Ms. Gita Kavarana (CSE Delhi India) further exposed the significance of traditional rainwater harvesting systems through her portrayal of a rich multitude of rainwater harvesting technologies and practices in the semi-arid and arid regions of Rajasthan and Gujarat. One of the most essential points stressed by Ms. Kavarana was the actual involvement of the public. She highlighted this by presenting an excellent video clip of a nationwide TV advertisement that was created to reenact and popularize ‘the importance of a raindrop’ amongst Indians.

India spent around US $ 650 billion on water supply projects during the past few years but this was to no avail. The solution has been recognized to lie in the utilization of traditional systems which make sense in the Indian sub-continent particularly due to the monsoonal concentration of rainfall in India. An interesting point made was that if one was to take a mere 3% of land in India and construct 30,000 tankas, a total of 9Mm3 of water can be harvested. It was reported that this is what all surface and groundwater resources are currently contributing in India.

Again the bottom-up role of the local people was stressed since ultimately they are the ones that manage these traditional forms of rainwater harvesting and the problems of bureaucracy in their management do not seep in.

A substantial number of diverse traditional RWH technologies coming from the Indian sub-continent were mentioned and explained. A short list of some of these included diversion channels, rain-fed storage structures, bamboo systems, qanats (practiced by the Mogul Kings in Uttar Pradesh), surangam, tanks or sagar, bandhas, chaukas or tobas and rapats All of these and much more were strikingly presented on a map of India revealing the rich diversity and dispersion of tradition across the country.

Unique rainwater harvesting systems which emerged from the several examples given included constructed underground rainwater harvesting systems in floodplain regions so as to reduce evaporation; in coastal areas the fresh water-salt water interface was used as a technique to harvest rainwater (known as Virda); and the glacial melt stored in mountainous regions was transferred to fields. Case study examples given included the Town of Dholavira of the Indus Valley where inhabitants tapped water from 2 channels that were constructed adjacent to the 2 sides of the city. In the Thar Desert local reservoirs called talab were made out of natural depressions and in urban areas roof water harvesting systems were used together with tankas that were constructed in courtyards. Temple sites made use of step wells (chadras), some of which went down to a depth of 2m. As for agricultural practices, embankments or khadin were built across slopes so that rainwater could gradually collect in fields which lay at the foot of slopes.

Social discipline emerged as a significant factor in the management of these structures. This was portrayed through the example given of people not being allowed to walk in the catchment designated for a certain RWH structure in order to maintain good water quality. Also an effort to clean the catchment prior to the monsoonal rains was considered a must. One must not exclude the role of knowledge. Traditional harvesting of rain could not have been possible without perceptive knowledge on the physical characteristics such as the geology of the area.

Ms. Kavarana claimed that the decline in the appropriate use of such systems came about due to the shift in the public’s mentality of water being a right and not a responsibility. Water was not considered a free good in the past. Fines existed for the violation of irrigation rules, for instance. Once a bureaucracy was introduced in India during British rule, community ownership of such systems was lost.

Conclusions from discussion
Therefore in conclusion to the Indian experience, the main lesson learnt was that rainwater harvesting is a tool for social mobilization since it empowers people and enables proper governance of water resources. Ms. Kavarana ended by linking this lesson to what CSE is doing today. CSE believes in public involvement and raising awareness. Water harvesting manuals have been created and dispersed, whilst workshops and advisory centres have also been set up.

Bridging Traditional RWH Techniques with the Present
Dr Theib Oweis innovatively linked the past two presentations that focused on traditional and historic perspectives with the present day. Bridging the gap between traditional and modern water technologies is a challenge since people often confuse techniques with indigenous knowledge. There is a growing perception that older techniques are far better than modern techniques.

This point was illustrated by the ceramic pot technology for small scale irrigation, which was a success a long time ago however one has to question whether it is still suitable today and whether there is a better technology now.

Indigenous knowledge has been useful in creating modern techniques. For instance drip irrigation technology, a relatively modern concept, came into being a long time ago through the ceramic pot technique. In the Negev desert a concave rock was used to condense water and collect the condensed water in hollows or basins that were placed beneath the rock. Today this ancient technique has led to drip irrigation since materials are cheaper and more affordable.

However a case in point where indigenous knowledge has not been applied appropriately is for instance in submerged land levelling, a technique that was essential to improve rice production. In Egypt oxen were used for levelling and today expensive and often unaffordable machinery is used. Another example given was that of head or energy required to get water from the aquifer. To do so qanat technology evolved. Modern achievement of head is through pumping which has led to abuse and over abstraction.

The examples Dr. Oweis illustrated revealed that it cannot be assumed that indigenous techniques are ideal for all times. It is Indigenous Knowledge combined with advanced science that ensures efficient application of modern technologies today. To indicate that this is possible Dr. Oweis highlighted the improvement of traditional agricultural RWH technologies by making the catchment more effective in transferring water. Contour bench terraces in Tunisia and Yemen, wadi bed stone walls, contour ridges and laser-guided contour bunds, as well as semi-circular bunds in Tabia, Tunisia all reveal that manual and mechanical construction and techniques have been integrated.

Conclusions from discussions
It was concluded that indigenous knowledge can be applied to modern ways through research and thus there is an urgent need for documenting and communicating this knowledge. The importance of understanding the environmental costs that are induced by such technologies is also crucial. Traditional rainwater harvesting techniques cannot be blindly applied to any circumstance or situation. An impact assessment of their implementation has to be carried out prior to them being adopted.

 



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