Traditional groundwater storage structures such as cisterns, stepwells, tanks, and wells in India are well known and had cultural, religious, social, and utilitarian significance in olden times. They served as places to access groundwater, meeting places for women who came to fetch water, places for bathing and the performance of religious rituals, and community places for interaction and leisure.
The paper 'Baravas: An architectural exploration of the traditional groundwater storage structures of Puṇe, India' published in the journal Ancient Asia informs that these structures were crucial parts of the landscape of many ancient Indian settlements.
However, changing lifestyles and rapid urbanisation have gradually led to their disuse and very few of them survive today. The few that survive still help in meeting the water requirements of people in small towns and villages.
While research on the architecture of traditional groundwater structures in India continues to be limited, it can greatly help in gaining knowledge on groundwater management and hydrology that was practised in olden times in India and provide lessons in sustainable groundwater management in current times.
One of the traditional water harvesting structures found in the state of Maharashtra are the Baravas, or stepped ponds, built for storing groundwater. The paper discusses the architectural and hydrogeological features of baravas, their socio-cultural and religious significance and their relevance in present times by studying two of them built during the 14th century at Mancara and Loṇi Bhapkara near Pune.
What are Baravas
Baravas are modified versions of kuṇḍas or ponds that are built with steps resembling a funnel, with their size decreasing from top to bottom. They can be of any shape from square, oblong to octagonal and can be of variable depths depending on the level of groundwater.
They are different from tanks, which are large, shallow water reservoirs with an extensive catchment area as they are designed to store rainwater. Tanks do not penetrate deep inside the ground and are lined by parallel steps. The rate of evaporation of water stored inside the tanks is very high due to their exposed large surface area.
In contrast, baravas have a small surface area, they penetrate deep into the ground to access groundwater and they have steep steps on the sides. Since they are deep they have a limited surface area that is exposed due to which the rate of evaporation of water from them is low. Some baravas also have intermediate landings and steps that take one down to the water source.
Construction of the baravas
People in ancient times were well versed with the art of selecting a suitable site to construct the baravas so that they could yield good quality and quantities of water. A site was selected after observing the colour, texture, smell, and feel of the soil and kind of vegetation growing in the soil.
After the site was finalised, a lot of science and art went into the construction. For example, special care was taken to balance the pressure of the soil from the outer sides, hydraulic pressure from the inner sides and the weight of the steps. Thus, the baravas were constructed in such a way that the sides had a greater slope than the slope of the land outside.
Large steps to strengthen the inward pressure of the soil on the walls were made. In some cases, additional stones were set in between the steps to provide additional support to prevent them from sliding away, which were also used as seating platforms. Steps were joined either using a tongue and groove joint or by pouring molten lead in between their grooves to hold them together.
Some baravas have a well in the centre that is filled with groundwater from shallow aquifers or springs and it opens up to the top in the shape of a stepped inverted pyramid. The top portion of the baravas sometimes has a small outlet for draining out the water and maintaining the level of water and most of them have a parapet wall around their perimeter as a protective edge.
Baravas made invisible groundwater visible
Baravas not only served the purpose of quenching thirst but were also places for social gatherings, resting for travellers, places for relaxation and leisure. Baravas make invisible groundwater visible to the people.
During monsoon, their steps are invisible as the water level inside is highest. With the end of monsoon, the steps start becoming visible slowly, as the water level inside begins to fall gradually with all the steps being visible as the water level reaches its lowest. This greatly helped people in judging the quantity of water stored inside baravas by counting the number of steps exposed above the surface of the water.
The paper argues that modern water infrastructure often fails to generate spaces that encourage people to enjoy, admire and value groundwater and prevents people from viewing, hearing, touching and experiencing the presence of groundwater.
The barava architecture highlights the need to respect the traditional wisdom of the people who constructed them in olden times and work on creating alternate designs and technologies that make groundwater more visible to the people.
There is an urgent need to conserve such groundwater storage structures that have withstood the test of time and learn from the traditional wisdom of our ancestors that helped people respect and value groundwater.