Saturday, March 8, 2008

TRADITIONAL WATER RESOURCE MANAGMENT THROUGH INNOVATIVE TECHNIQUES

TRADITIONAL WATER RESOURCE MANAGMENT THROUGH INNOVATIVE TECHNIQUES

*Senior Programme Co-ordinator, GRAVIS, Jodhpur.
E mail: krajendra66@yahoo.com, krajendra66@gmail.com

ABSTRACT

In the desert region the rural communities face acute problem of drinking water. Water is the main theme of perennial human interest. Many traditional technologies exist for water harvesting through taanka, Naadi and beris etc. But due to introduction of tap water these technologies are left behind in towns. But in rural area with innovations in the traditional systems and participation of community in water conservation programmes, with initiatives of NGOs, PRIs and Government, the acceptability of the water harvesting systems is increasing. In this paper attempts are made to explain the traditional water resource management systems and the innovations such as catchment improvements, silt catchers, wire mess for inlet and outlet, a lead opening and masonry super structure. The innovations suggested in the structures are proving very useful and increasing the availability of yield by reducing the losses. Also the health and hygiene of the rural people is improving. In fact, the traditional water harvesting structures (Beri, Taanka and Naadi) is much more than a self reliance source of water for the community or a family asset.

KEYWORDS: Thar Desert, Water harvesting, Traditional, Taanka, Naadi, Beri, Innovations.

INTRODUCTION

In India there are about 2.34 million km2 of hot desert called ‘Thar’. About 85% of the Great Indian Desert lies in India and the rest in Pakistan. About 91% of the desert, i.e. 2.08 million km2, falls in Rajasthan covering about 61% of the geographical area of the state. The Aravali hills, older than the Himalayas, intersect the State to the north-east and in the west lies the great Indian desert the ‘Thar’. Thar Desert receives between 100 to 500 mm of rainfall every year, most of which is received between July and September. The sandy soils of the desert have a rapid infiltration rate of water, poor fertility, low humus content due to rapid oxidation and high salinity. All conditions are very hostile for the existence of life, yet, large human and livestock populations inhabit the area.

There is no province or district in the country where famines occur so frequently. The Rajasthan state has only 1% water resource, whereas area is 10% & population 5.1% of the entire country. 12 districts, which comprise 60% of the area of the state, fall within the Great Indian Desert or Thar. Thar is the most populous desert in the world 64% of its population resides in the Thar despite scanty rainfall with all its variations, timing and intensity. The rural economy is predominantly based on agriculture and animal husbandry. Livelihood of people is dependent on monsoonal behavior. Production of crops and fodder for animals which exceed the number of people is entirely a variable of the quantity and frequency of showers. Rains 16-25% below normal lead to drought and scarcity. Rajasthan is facing probably the most severe drought of the century and that too for the third year in succession.

Water is basic necessity and provided to those who other wise have no access to it is a blessing. Rajasthan is a state where resources of water are very scare. Our ancestors developed scientific techniques to conserve water and combined it with religious teachings so that people would follow certain rules and beliefs concerning the use of water. These rules become a part of their life. Many generations ago, a few valiant people developed techniques to conserve water, which are still adopted by us today. These traditional techniques are our only weapons to combat the scarcity of water worldwide.

TRADITIONAL WATER HARVESTING TECHNIQUES

For a desert region, water is the most limiting element in biological activity and its management is central to the survival of the population settled therein. To make most of the low and uncertain rainfall, desert dwellers over the generations have evolved and adopted several techniques to augment water supplies for drinking, domestic, agricultural and livestock purposes. Earlier setters with poor material resources and inadequate means of transport spent their fortune in digging a well several meters deep. As settlements grew and expanded in numbers, the people thought of augmenting the supplies with rainwater harvesting structures. People harvest rainwater, harnessing meager surface run off in water harvesting structures like naadi, taanka and beris.

NAADIS

Naadi is a man-made village pond. Rainwater from surface runoff is collected in a natural depression in the land and an embankment to hold the water in is built behind. The naadi or pond is accessible to all people in the village, livestock and wildlife and is also used for replenishing taankas that have been depleted of rainwater.
Naadis are a very old desert tradition. A Rajput landlord reportedly built a naadi in memory of his wife Sunderi at Akhadhana village some five hundred years ago. Many villages were originally established near areas that could easily be made into a naadi, which would often serve as the only source of drinking water. With the introduction of piped water, however, many naadis have been left to silt up and remained unused or forgotten and the naadi tradition was not carried on as new villages were established.

TAANKA

Taanka is a rain water harvesting techniques. It is meant for drinking water purpose of a family or a small group of family. Though originally found in the desert towns, the system has since gained immense popularity in rural areas. In phalodi, barmer and balotra region a rural tanka was found comprising 6.1 m deep, 4.27 meter long and 2.44 meter wide. This technique of harvesting rainwater was perfected to a fine art in arid region of western Rajasthan.

Bikaner was founded by Rao Bika in 1489 AD. The choice of Bikaner as an urban center seems to have been strongly influence by the availability of tracts of mudiya kanker which possess excellent run off characteristics. This facilitated rain water harvesting through and elaborate network of tanks. The catchments area (Agor) of these tanks was treated as a sacred area where human activities like defecation were prohibited. In towns around Bikaner, there was an abundance of tanks. The more important ones being, Kolayat with a catchment area of 14,900 ha, Gajner 12,950 ha. and Ganga sarovar 7,950 ha. the water needs of the town were met by the innumerable tanks in and around Bikaner, together with the wells and taankas that each house traditionally built for harvesting rain water from the roof tops. The water from the taankas was used only for drinking purposes. If in any year there was less than normal rainfall and the taankas did not get filled, water from near by wells and tanks would be obtained to fill the house hold taankas. In this way, the people of Bikaner were able to meet their water requirements.(Anupam Mishra,1995)
BERI
Beri are community/Family wells found across Rajasthan and are used mainly for drinking water. The beris could be percolation wells which lie close to the bed of Naadi or Khadin, and utilized the deeply percolated water of an occasional, past good rainfall event. The deeply percolated water is drawn through the beri after the naadi has dried out. There is another variation of a beri found where it is a huge, under ground hollow, 5 – 10 meter diameter rain water harvesting well with a small catchments for tapping the run off. In both the above cases the substrata is made up of shale or clay beds. The low porosity of shales permits efficient storage. Beri holds water for a long time because of almost negligible water evaporation. The capacity of the cistern is so large that once filled, the storage is sufficient for 2 years at a stretch. Because of imperviousness of the strata, seepage losses are very small.

PRESENT SCENARIO AND INNOVATIONS

Unfortunately with the introduction of tap water, catchment and roof top harvesting has been rapidly declining , especially in the towns of the Thar desert. Near Bikaner today, except for Harshalao, the catchment areas of all the tanks have been destroyed. Some of the old tanks like the Jassolai, Baghinada and Rangolai have been wiped off the map of Bikaner. But the rural area is now started practicing the traditional water harvesting methods due to participation of NGOs, PRIs and Government, in facilitating funds and innovations in the structures, by making permanent structures of masonry or concrete, for better acceptability.

The Naadi needs desalting from time to time. Cleaned and deepened naadi collects more water. Due to rains and blowing winds the nearby sand slowly accumulates in the naadi bed making it shallow. The work of taking out sand is known desilting of naadi. Traditionally, villagers used to do this work in groups as community activity on Amavasya – no moon day – once in a month. At present people are not interested in cleaning the naadi. The community feeling is lacking and no longer do people get together to clean the naadi.

People are more willing to contribute funds rather than their own labour. Many people go out of the village for work and are unable to contribute their labour. However potters still continue to remove the clay from the naadi bed to makes pots.

The Naadi at Akhadana was cleaned by such efforts on the following years; (Gravis 2003)

1980: By village people collectively by self efforts;
1991: By the government
1995: By NGO (Gravis) on 50 % subsidy;
2000: By NGO (Gravis) on 50 % subsidy
2001: By the government under famine relief work.

The NGOs initiated community participation to preserve, basic community norms laid on traditional wisdom, to ensure longer sustainability of a Naadi. The norms were once again made and enforced:

No trees on the naadi wall will be cut down. Every care is taken not to deforest the catchments area (Agore) of Naadi. Live stock is not allowed to enter, disturb soil, urinate or defecate in the catchments area. Human beings are also not allowed to enter the catchments and urinate or defecate in it. No one will wash his feet, cloths or take a bath. The tyre of an animal cart will not touch the water. Animals will be removed immediately after they have drunk water.

Innovations: To increase the yield of Naadi, the catchments of naadi are improved and the area of catchments increased through diverting Aad (bunds). The masonry structures are constructed as a retaining wall in the lower side of the Naadi, which keeps Naadi pal stable and stops the mud to come down. A pucca overflow structure is constructed to allow excess water to flow away.

The traditional Taanka is now modified, based on the feedback of rural communities and study in the desert area. The purpose of modification is to increase its capacity to hold more water of better quality, for longer period and to suit the local conditions.

Innovations: A stone masonry or concrete taanka is constructed now a days. The dimensions of tanka are 3 meter diameter and 3.6 meter height. The recommended size of catchment for the taanka, after studying the rainfall probability (212mm) and runoff coefficient (0.20) is 500 sq.m. for six member family. A silt catcher is introduced near the inlet of the taanka to prevent entry of silt or dust in to taanka and prevent contaminating water. A lid opening on top of taanka facilitates entry during cleaning and prevents dust getting in. An outlet is provided for overflow of excess water thus saving the taanka from damage due to excess of water. A filter (Wire mess) is provided at inlet and outlet of tanka to prevent entry of suspended solids and dust/silt into taanka. The efforts are on for improvement of catchments by various methods like murrum compaction, mixing bentonite into the soil etc. for getting more runoff from the catchments and ultimately more water in the taanka.


The Beris are innovated for getting more yield and better quality of water and the suggested innovations are listed below.

Innovations: For percolation/seepage beri a raised circular platform is constructed to permit withdrawal of water even when the surrounding land is inundated. More importantly, it prevents the influx of raw rainwater with all the floating and suspended organic pollutants and soil sediments. The movable lid provided ensures an easy approach for deepening and maintenance of the beri.

The rain-water storing beris have been improved by lining the duct. Further a raised platform with inlets for rainwater is added at the duct mouth to provide further stability. This platform is movable to permit easy access for de-silting/maintenance of underground cistern. A small opening with iron lid is provided in the roof of the platform for ease of drawing water. Silt catcher and inlet with wire mess is provided to reduce the entry of silt and sediment load in the beris. The natural catchments around one acre are used and the surface is maintained for developing runoff as per the improved suggested modifications.

CONCLUSION

The traditional water harvesting techniques of the Thar needs to be preserved and community participation is needed for the same. The innovations suggested in the structures are proving very useful and increasing the availability of yield by reducing the losses. Also quality of water is improved because of providing silt catchers and filters at the inlet and outlets. The health and hygiene of the people is improved. Also the life of structure is increasing because of permanent structures. The catchment improvements are helping in increased yield to the structures. The NGO’s playing vital role in the area by funding the expenses for the structures but participation of the community is kept compulsory by providing the man power for the construction and maintenance work. This is a good practice not to provide funds without the participation of the beneficiary. More awareness in the people about the importance of water conservation and its innovated methods for preservations will kick the problem of survival for drinking water in the Thar Desert.

ACKNOWLEDGEMENTS

The authors acknowledge the support of Gramin Vikas Vigyan Samiti, Milk Man Colony, and Jodhpur for providing access to the information about works in progress in Thar for water conservations and community participation for elevating the lifestyle of the desert people. Also author appreciates the efforts of the organization in upliftment of the rural communities of Western Rajasthan.