Our ancient religious texts and epics offer an insight into the water storage and conservation systems that prevailed in the days gone by. In ancient India, people believed that forests were the 'mothers' of rivers and worshipped the sources of these waterbodies. In the forests, water seeps slowly and gently into the ground thanks to the vegetation. This groundwater, in turn, feeds wells, lakes and rivers. Protecting forests means protecting water catchments.

The Indus Valley Civilisation that flourished along the banks of the river Indus and other parts of western and northern India around 5,000 years ago, had one of the most sophisticated urban water supply and sewage systems in the world. The fact that the people were well acquainted with hygiene can be seen from the covered drains running beneath the streets of the ruins at both Mohenjodaro and Harappa. Another very good example is the well planned city of Dholavira, on Khadir Bet, a low plateau in the Rann, in Gujarat.

A study by oceanographers from the National Institute of Ocean Technology (NIOT) dates the antiquity of India’s water harvesting culture as far back as 3,000-13,000 years. On the sea bed in the Gulf of Cambay, at a depth of 90 metres, the sonar of a survey ship picked up images of a submerged township. Here there was a water storage tank measuring 700 metres by 800 metres, and five metres deep, and several public bathing tanks.

In arid and semi-arid regions of India, the tank system was the traditional backbone of agricultural production. Tanks were constructed either by bunding or by digging into the ground to collect rainwater.

The desert state of Rajasthan receives hardly any rainfall. But people have adapted to the harsh environment by collecting whatever rain falls. In ancient times, houses in parts of western Rajasthan were built so that each had a rooftop water harvesting system. Rainwater from these rooftops was directed into underground tanks. This system can be seen even today in all the forts, palaces and houses in the region.

The bawris of Rajasthan are architectural wonders. Some of the structures are between 150 and 1,000 years old. They also helped recharge groundwater channels.

In some tanks in Jaisalmer, the statue of an elephant at a lower level and a horse at a higher level marked the future availability of water. For example, if the level of the water touched the elephant’s feet it meant water would be available to the locality for two years. If the level rose and touched the ears of the horse, that indicated the availability of water for five years. Despite being a desert area Jaisalmer never had a famine, says India’s ‘water man’ Rajendra Singh.

Large bunds to create reservoirs, known as khadin, dams called johads, tanks, and other methods, were built to check the flow of water and accumulate run-off. At the end of the monsoon, water from these structures was used to cultivate crops.

Similar systems were developed in other parts of the country too. These are known by various local names -- jal talais in Uttar Pradesh, the haveli system in Madhya Pradesh, ahar in Bihar.

One of the oldest water harvesting systems is to be found around 130 km from Pune, along Naneghat in the Western Ghats, where a large number of tanks were cut into the rocks to provide drinking water to tradesmen who used to travel along this ancient trade route. Each fort in the area had its own water harvesting and storage system in the form of rock-cut cisterns, ponds, tanks and wells that are still in use today. Forts like Raigad also had tanks that supplied water.

Underground baked earthen pipes and tunnels to maintain the flow of water and to transport it to distant places are still functional at Burhanpur in Madhya Pradesh, Golkunda and Bijapur in Karnataka, and Aurangabad in Maharashtra.

In Himachal Pradesh and Uttaranchal, small tanks were constructed to allow spring water to accumulate; they were subsequently covered by a roof. These structures, that resemble little temples, are called naula in Uttaranchal. Other methods of water harvesting in Uttaranchal include dharas, panderas, mangras, khals, chals, guhls and gharats.

Guhls are the same as the kuhls of Himachal Pradesh. Water from a river or a stream is diverted into a narrow drain -- a guhl -- at a point much higher than the village or fields. Water is thus transported long distances by gravity.

In Hamirpur, Kangra and Mandi districts of Himachal Pradesh, rectangular deep pits are dug into the hard rock on hill slopes to collect rainwater. These are called khatris. There are khatris that collect rainwater from rooftops as well.

A system that impounds rain run-off, called zabo, is practised in Nagaland. The hill slopes of Nagaland have terraced fields. Water from the highest terraces is allowed to flow down and is collected in pond-like structures in the middle terraces. Cattle yards are located immediately below such ponds. The lowermost terraces have paddy fields, where, again, water percolating from the higher terraces is impounded.

In the Mettur area of Kolar district, in Karnataka, village ponds built on chettu, or weathered granite, held enough water for both the local population and their luxuriant sugarcane crop.

The Gangetic plains, constituting the huge agrarian belt of Uttar Pradesh, Bihar and West Bengal, featured a large number of ponds (locally called talab, talayya, pokher, pukur, etc). These were either remnants of cut-off meanders of rivers (oxbow lakes) or were dug by the community. They were and still are ideal water harvesting structures.

In certain tracts of Madhya Pradesh such as Tikamgarh, and Udaipur in Rajasthan, small dry ponds were used to cultivate paddy until the next season when the pond was again available for harvesting water.

-- Mita Banerjee
(Mita Banerjee is a Pune-based journalist)

InfoChange News & Features, June 2008