Traditional Water Conservation Systems in the State of Rajasthan
In popular imagination, Rajasthan is a land of chivalry and rugged forts set against the backdrop of a desert landscape, with camels traversing unending sand dunes. The majesty of the forts at Chittor, Udaipur, Mehrangarh, Kumbhalgarh or Ranthambore to name a few is such that it draws people from far and near.
But there is another equally heroic tale woven around architectural marvels that testify to the collective ecological wisdom that once energised the region. While doing my PhD research on understanding human negotiations with semi-arid and arid environments of Rajasthan during medieval times, I discovered that the land of forts was equally a land of man-made water bodies, exemplifying a culture of valuing each drop of precious water.
On one hand are Rajasthan’s massive man-made lakes like the Raj Sammand, Bal Sammand, Pichhola, Amar Sagar and Garsisar, some perennial and some seasonal. On the other hand, the state boasts of a variety of smaller forms of water architecture such as baories, tankas and joharas which were the immediate lifelines of communities. Together, these diverse man-made water bodies represent the ingenuity of traditional water harvesting systems in an arid and semi-arid landscape that have formed the basis of Rajasthan’s richly diverse cultural heritage.
With the coming of piped water supply and tube wells, most of these forms of water architecture have fallen prey to neglect. But if the creeping water crisis across the country and the world is any indication, it is time to learn anew from examples of local genius that were devised in the face of scarcity.
Much of the region is located in an area geographically known as the little Indian desert, separated from the Ganga-Yamuna doab by the Aravalli range of mountains. The Aravallis form a topographic barrier that deprives this region of the bounties of water-laden monsoon winds. Factors such as scant and occasional rainfall, absence of perennial rivers combined with brackish ground water, made rain-water harvesting imperative for communities living in the area, as elsewhere in the state. But the Shekhawati region faced an added complication. Its sandy soil, unlike loamy soil, drained quickly owing to its porous nature. Hence, storing water in any depression or pit over a length of time was made more difficult.
kund or kundi look like an upturned cup nestling in a saucer. These structures harvest rainwater for drinking, and dot the sandier tracts of the Thar Desert in western Rajasthan and some areas in Gujarat. Essentially, a circular underground well, kunds have a saucer-shaped catchment area (called Agor) that gently slopes towards the centre where the well is situated.
A wire mesh across water-inlets prevents debris from falling into the well-pit. The sides of the wellpit are covered with (disinfectant) lime and ash. Most pits have a dome-shaped cover, or at least a lid, to protect the water. If needed, water can be drawn out with a bucket. The depth and diameter of kunds depend on their use (drinking, or domestic water requirements). These are owned by people with money to invest and land in which to construct them. For the poor, large public kunds were built.
Kuis / Beris
Kuis are found in western Rajasthan, these are 10- to 12-m-deep pits dug near tanks to collect the seepage. Kuis can also be used to harvest rainwater in areas with meagre rainfall. The mouth of the pit is usually made very narrow. This prevents evaporation of the collected water. The pit gets wider as it burrows under the ground, so that water can seep in into a large surface area. The openings of these entirely kuchcha (earthen) structures are generally covered with planks of wood, or put under lock and key. The water is used sparingly as a last resort in crisis situations.
Baoris or Bers are community wells, found in Rajasthan, that are used mainly for drinking purposes. Most of them are very old and were built by banjara (mobile trading communities) for their drinking water needs. They can hold water for a long time because of almost negligible water evaporation.
Jhalra is a local name given to step wells. Jhalaras were human-made tanks, found in Rajasthan and Gujarat, essentially meant for community use and for religious rites. Often rectangular in design, jhalaras have steps on three or four sides. Jhalars are groundwater bodies which are built to ensure easy and regular supply of water to the surrounding areas. The jhalaras collect subterranean seepage of a talab or lake located upstream. The water from these jhalaras was not used for drinking, but only for community bathing and religious rites. Jhodhpur city has eight jhalaras, two of which are inside the town and six are found outside the city. The oldest jhalara is the Mahamandir Jhalara, which dates back to 1660 AD.
A Nadi or dug-out village pond is the oldest and still the most prevalent storage structure for rainwater harvesting from an adjoining natural catchment during the rainy season. The site was selected by the villagers based on available natural catchments and its water yield potential. The water stored in a nadi is generally used for drinking by livestock and human beings. A nadi also acts as a source of groundwater recharge through seepage and deep percolation. It is estimated that the recharge from a nadi covering 2.25 ha and having a storage capacity of 15 000 m3 in an alluvial area may induce a groundwater recharge of 10 000 m3 in one rainy season. The location of the nadi had a strong bearing on its storage capacity due to the related catchment and runoff characteristics.
The Tanka (underground cistern) is another major source of drinking water in western Rajasthan. It is constructed in a circular or rectangular shape, normally on bare ground where surface runoff can be diverted to the tanka by creating a clean catchment around it. A traditional tanka constructed with lime plaster and thatched with bushes has a life span of 3–4 years. In this way, the people of Bikaner were able to meet their water requirements.
A johad is a traditional water harvesting structure. Johads are small earthen check dams that capture and conserve rainwater, improving percolation and groundwater recharge, constructed by people using their own skills, resources and indigenous knowledge; these have revolutionized life in rural Alwar, Rajasthan. These have helped the farming communities from abject poverty to prosperity, a miraculous transformation under the leadership of Tarun Bharat Sangh and its leader Rajendra Singh, the Water Man of Rajasthan.
The johads are simple, usually semi-circular, mud barriers built across the hill slopes to arrest the monsoon runoff. They are built across a slope to arrest rainwater; bound on three sides by the natural slopes of hills. The fourth side, a mud wall usually semi-circular in form holds back the monsoon runoff. The height of the embankment varies from one johad to another, depending on the site, water flow, contours, etc. In some cases, to ease the water pressure, a masonry structure is also added for the outlet of excess water. The water storage area varies from 2 ha to 100 ha. The optimal storage created was 1000–1500 m3 per hectare of cultivated area. The cost of the storage created varied from Indian Rupee 0.2 to Rs.1.50/m3 , with an average of Rs.0.95/m3 . The villagers shared the cost, supplied labour and materials like stone, sand and lime, which were locally available and contributed 70–90% of the total cost. The distinctiveness of these structures lay in their low cost, simple design, easy construction and maintenance.
These indigenously designed structures stood the test of time and the ravages of heavy rainfall. The water collected in a johad during the monsoon is directly used for irrigation, drinking, livestock and other domestic purposes, and penetrates into the sub-soil. This recharges the groundwater and improves the soil moisture in vast areas. Also, during the dry season when the water gradually recedes in the johad, the land inside the johad itself becomes available for cultivation.