Having a varied terrain India poses a challenging prospect when it comes to water conservation and water usage. One particular solution is thus not applicable to different areas of the country. In addition, while the use of technology and advancement of science can provide ready solutions, sometimes, traditional time-tested ways can help fulfill the requirements of people in a much more effective way.
Here is a list of some of the traditional water conservation methods that are still in use:
Kuls are diversion channels that carry water from a glacier to village. Often spanning long distances, with some over 10 km long, kuls have been around for centuries. They are the lifeline of people of Spiti valley of Himachal Pradesh and in Jammu too.
Kul starts at the glacier, which is to be tapped. Keeping the head clear of debris is achieved by lining the sides of Kul with stones which ensure that there is no seepage or clogging. The Kul leads to the village where the water is stored in a circular water tank. The water is drawn from here are per the need of the village.
Bamboo Drip Irrigation System
This system of water conservation and usage of stream and spring water is done using bamboo pipes. Practised in Meghalaya, its primary purpose is to irrigate plantations. This 200-year-old system involves 18-20 litres of water entering the bamboo pipe system every minute to irrigate the fields downhill. A brilliant drip irrigation system, it uses bamboos of various sizes and reduces the output to to 20-80 drops per minute, which is splendid for betel leaf and black pepper crops.
The whole irrigation system is made up of different forms of bamboo pipes of varying cross sections which take the water from perennial springs on the tops of the hill. The flow of water is controlled by the changing pipes positions. The method is so efficient that it enables the water to be dropped at the base of the plant to ensure there is no runoff and wastage.
Alwar district of Rajasthan is one of the driest regions in India with water scarcity being a common occurrence. After the drought of the 1980s, the villagers attempted to revive the traditional method. Johad, a crescent shaped small check dam built from earth and rock to intercept and conserve rainwater, was thus reinvented. This helps to improve percolation and increases groundwater recharge.
By recharging the aquifer below the surface, Johads have helped increase agriculture in the area. Usage of Johads has also helped increase the flow of river Arvari, making it a perennial river now. It earlier used to dry off after the monsoon.
Zabo means impounding water. Known locally as the Ruza system, this system is a unique combination of water conservation with animal care, forests and agriculture. Mostly practised in Nagaland, Zabo is used to deal with a lack of drinking water supply. During monsoon, rainwater that falls on the hilltops is collected into the pond like structures that are carved out on the hillsides. The water is then passed onto cattle yards below from where the water enters the paddy fields rich in manure.
The paddy fields can be used to rear fishes as well thus giving a yield of about 50-60 kg/ hectare as extra output. Quite a few medicinal plants and herbs are also grown nearby. These ponds are made in such a way that water distribution is uniform.
One of the oldest water conservation systems in India, Eri (tank) of Tamil Nadu is still widely used around the State. With over a third of irrigation in the State being made possible due to Eri, the traditional water harvesting system plays an important part in the agriculture. They also have other advantages such as prevention of soil erosion, recharge of groundwater, and flood control.
Eri can either be fed through channels that divert river water, or rain-fed ones. They are usually interconnected to balance the water in case of excess or lesser supply.
Khadin is a water conservation system designed to store surface runoff water for the purpose of agriculture. It entails an embankment built around a slope, which collects the rainwater in an agricultural field. This helps moisten the soil and helps in preventing the loss of topsoil. Additionally, spillways are provided to ensure that excess water is drained off.
This system of water conservation is common in the areas of Jaisalmer and Barmer in Rajasthan. A dug well is usually made a bit further from Khadin to additionally take advantage of groundwater recharging that happens around the structure.
Developed by the nomadic Maldhari tribes of Rann Of Kutch, virdas are shallow wells dug within a natural depression(Jheel). Since the area around is very saline, when rainwater seeps down the soil, it collects over the saline groundwater due to the difference in density (rainwater being less dense). The tribesmen identify areas on basis of flow of the monsoon runoff and build these shallow wells.
This smart method helps them separate freshwater from saltwater and provide water for a variety of purposes. Vegetation is planted along virdas to help protect them.
Surangam is a traditional water conservation system present in areas of Karnataka and Kerala. The terrain of the area makes it impossible for people living around to survive only on surface water. Thus a complex labyrinth of fine tunnels are built which constitutes horizontal wells dug in laterite rocks. The Surangam can be of varying length and can even go up to 300 metres. Water is collected into a storage tank using gravitational force. Vertical shafts are provided for airflow.
The population nearby depends mainly on these horizontal wells for their water requirements. They are also used to irrigate crops such as paddy and coconut. What is also important that the water from Surangam is of good quality.
This is a water conservation technique indigenous to South Bihar. Due to a variety of reasons including sandy soil, temporal river flow, low groundwater levels etc, floodwater harvesting is considered as the most suitable option for the area.
Ahar consists of a catchment basin embanked on three sides, at the end of a rivulet or a canal that leads from a river. Pynes are artificial channels, which were constructed to use river water for agriculture. The process starts from the river, from where the water goes to pynes and eventually lands up in an ahar. Although the system suffered under British rule, it has again been rejuvenated for agricultural purposes, especially in the district of Gaya.
With the look of an upturned cup nestling in a saucer, these water conservation structures are built to harvest rainwater. Usually dotting the areas of Rajasthan and Gujarat, they have a saucer shaped catchment area sloping towards the centre to where the well is situated.
To prevent debris from falling into the well, a wire mesh is used while the sides of the well pit are covered with lime and ash, which act as a disinfectant. Usually, the depth and diameter of these kunds depend upon the purpose of use i.e. drinking or for domestic usage.
There are many other methods too that are practised in various combinations. These methods have been around for hundreds of years, and with a lot of areas suffering from water scarcity, it may be time to revisit some other traditional methods to help innovate new ways of revival.
Using these methods, we can help combat monsoon failure by rain water conservation