Traditional water harvesting 4

Traditional water harvesting in Thar region of India.The presentation shows various methods employed for water conservation and recharging in Rajasthan and Gujarat in Western India.

1. TRADITIONAL WATER HARVESTING IN INDIA Part I V THAR DESERT REGION WATER MANAGEMENT FORUM The Institution of Engineers (India) http://www.wmf-iei.org/index.php/ 1

2. Paar system A common water harvesting practice in the western Rajasthan region. It is a common place where rainwater flows from the agar (catchment) and in the process percolates into the sandy soil. In order to access rajani pani (percolated water) kuis / beris are dug in the agor (storage area). Kuis or beris are normally 5 to 12 meters deep , constructed in masonry. Normally six to ten of them are constructed in a paar , numbers decided depending on size of the paar Rainwater harvested through paar is known as Patali paani . Interlinkages between traditional water harvesting system and land development measures act as a drought-proofing mode. Fodder and Rabi crops can be grown in adjoining land, which can be irrigated perennially by the paar system.

3. Nadis (Village ponds ) Village ponds, found near Jodhpur and Barmer in Rajasthan. Used for storing water from adjoining natural catchment during the rainy season. Site is selected by the villagers based on an available natural catchments and its water yield potential . Water availability from nadi would range from 2 to 12 months after rains . Those are dune areas range from 1.5 to 4 meters and those in sandy plains varied from 3 to 12 metres . Location of the nadi had a strong bearing on its storage capacity due to related catchment and runoff characteristics. Water stored in a nadi is generally used for drinking by livestock and human beings . It acts as a source of groundwater recharge through seepage & deep percolation. A poorly maintained nadi suffers high water losses through evaporation, seepage and biotic interference resulting in rapid siltation and pollution.  E conomic life of a nadi is 25 years, however with due care in repair, maintenance and desilting , a nadi may function for a much longer life.

4. Khadin A khadin , also called a dhora , is an ingenious construction designed to harvest surface runoff water for agriculture . It is popular in hyperarid part of Rajasthan. Runoff from upland and rocky surfaces is collected in adjoining valley against an earthen embankment having a masonry waste weir for outflow of run-off excess . Its main feature is a very long (100-300 m) earthen embankment built across the lower hill slopes lying below gravelly uplands. Sluices and spillways allow excess standing water to drain off for crop cultivation. The khadin system is based on the principle of harvesting rainwater on farmland and subsequent use of this water- saturated land for crop production.

5. A khadin farm is developed on the basis of rainfall probability, available catchment area and its runoff generation potential. Apart from the submerged area, khadin beds are cultivated from top to bottom on receding moisture. Ponding of water in a khadin induces continuous groundwater recharge. The perched subsurface water is extracted through bore wells developed in the khadin or in the immediate vicinity downstream.

6. Tankas (small tank ) U nderground tanks, found traditionally in most Bikaner houses, Dwarka and old houses of Ahmedabad cities in Pol area Built in main house or in the courtyard. C ircular holes made in the ground, lined with fine polished lime, in which rainwater was collected . O ften beautifully decorated with tiles to keep water cool . W ater used only for drinking . In any year having less rainfall, water from nearby wells and tanks would be obtained to fill tankas . Surface runoff can be diverted to the tanka by creating a clean catchment around it. Constructed with lime plaster and thatched with bushes has a life span of 3-4 years. With decomposition of brush wood, falling of leachate and entry of foreign material with runoff through open inlet, quality of stored water in the tanka deteriorates over time making it unhygienic for drinking.

7. Kunds / Kundis Covered underground tanks ,Developed for tackling drinking water problems. Looks like an upturned cup nestling in a saucer. Harvests rainwater for drinking, and dot the sandier tracts of the Thar Desert in western Rajasthan (also in Gujarat and Uttar Pradesh) and in areas where the limited groundwater available is moderate to highly saline. Provides convenient, clean and sweet water for drinking. Has a saucer-shaped catchment area 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 well-pit are covered with (disinfectant) lime and ash.

8. Baoris / Bers Baoris or bers are community wells, found in Rajasthan, that are used mainly for drinking. Most of them are very old and were built by banjaras (mobile trading communities) for their drinking water needs. They can hold water for a long time because of almost negligible water evaporation. The baoris are not merely tanks, but also groundwater recharge facilities.

9. Vav / vavdi / Baoli / Bavadi Traditional step-wells are called vav or vavadi in Gujarat, or baolis or bavadis in Rajasthan and northern India . These were wells - stepped wells in fact. Stepped and moving into the bowels of the earth, some five to six storeys in height. Designed to bring the people and Gods together, these wells attempted to entice Gods to leave their abodes for a cool drink of water - the elixir of life. These consisted of two parts: a vertical shaft from which water was drawn and surrounding it were the inclined subterranean passageways, chambers and steps, which provided access to the well. The galleries and chambers were carved generously, which became cool retreats during summers.

10. Basic difference between step-wells on the one hand, and tanks and wells on the other, was to make it easier for people to reach the ground water, and to maintain and manage the well.  A typical well is made up of the Mandapa (the entrance pavilion), which forms the main approach at the ground level ; the Kuta (the flight of steps) leads down to the water or Kund (tank) at the bottom. Most of the wells are decorated with sculptures on all available surfaces. When located within or at the edge of a village, it was mainly used for utilitarian purposes and as a cool place for social gatherings. When located outside the village, on trade routes, they were often frequented as resting places. Many important step-wells are located on the major military and trade routes from Patan in the north to the sea coast of Saurashtra . When used exclusively for irrigation, a sluice was constructed at the rim to receive the lifted water and lead it to a trough or pond, from where it ran through a drainage system and was channeled into the fields.

11. Jhalaras were human-made tanks, found in Rajasthan and Gujarat, essentially meant for community use and for religious rites. They were constructed at exorbitant cost and were often monumental, beautiful mansions with fine embroidery stone works covering large areas and were associated with religion and culture. Often rectangular in design, jhalaras have steps on three or four sides . Jhalars are ground water bodies which are built to ensure easy and regular supply of water to the surrounding areas. The jhalars are rectangular in shape with steps on three or even on all the four sides of the tank . The jhalaras collect subterranean seepage of a talab or a lake located upstream . Water from these jhalaras was not used for drinking but for only community bathing and religious rites Jhalaras