In the recent past, Dr. Dipul Choudhury from Guwahati (Assam), managed to ensure rainwater harvesting arrangements in his newly constructed multistoried building at Tarun Nagar, Guwahati (Assam).
Rainwater harvesting enables us to overcome the problems of irregular and inadequate water supply or water supply of poor quality and also reduces the dependence on ground water. The process involves storing rain water that falls within one’s premises and re-using it after basic treatment. Treated rain water is safe not just for cleaning and washing but also for cooking and personal consumption. In the long run, rainwater harvesting will also replenish the rapidly depleting ground water levels through recharging and lead to water security and sustainability.
In Guwahati, the responsibility of providing drinking water supply lies generally with the local body / Urban Water Supply and Sewerage Board, Assam. However, the present coverage with Piped Water Supply network is hardly 30-35% of the population and that too, is erratic with respect to its frequency and quantity of supply. Furthermore, the authorities to meet the increasing demand arising out of extraordinary pace of urbanization. Due to the absence / unreliability of public water supply, residents become dependant on own source ( ground water through deep tube well ) or some commercial agencies or water vendors.
Every year there is water crisis in the greater Guwahati area specially during the winter season and such a situation happens only because of depletion of ground water table. Most of deep tube wells and ring wells dry out and the residents are compelled to procure water from private vendors at a premium.
Dr. Choudhury is very much concerned about the pressing environmental issues, especially about the over withdrawal and usage of groundwater, resulting in depletion of ground water table. He has years of experience of rainwater harvesting in his residence since 1991, of course in a small sale to cater for own household needs and recharging within the campus. Before starting of rainwater harvesting in his residence, the rainwater from his campus was led to the drain, like other households in his locality and finally leading it to the road side drain. Considering that as a huge loss and wastage, he made up his mind to make good use of the rainwater collected from the roof of his residence. Accordingly, in the year 1991, he created the necessary arrangements and started collecting the rainwater and to utilize the same for the households needs and then to recharge the ground water for its augmentation. Such arrangement reduced his dependence on the other sources of water for his household works.
Being quite satisfied with the fruit bearing results from the experience of rainwater harvesting in his own residence, Dr. Choudhury initiated on his own to ensure alternative water sources in the form of harvested rainwater collected from the roof top and to use it after basic treatment, in his newly constructed multistoried complex with the sole aim to reduce the dependence on the deep tube well and also to take care of the very real threat of water shortage due to depletion of ground water table. Because of his keen interest to do something on his personal capacity and also to set an example for others, he started rainwater harvesting and recycling of greywater for recharging in this new construction.
The provisions include rainwater pipes for leading the rain water from terrace to a baffled wall sedimentation followed by sand filtration and finally to the under ground ( partly ) tank with a storage capacity of more than 1,00,000 (one lakh) litre. The filtration process is provided with backwash arrangement also for periodic cleaning of the filter. Arrangements are made for periodic cleaning of the terrace also and utilizing the overflow water for recharging the ground water table. Furthermore, the multistoried complex facilitated with the treatment of its waste water in an Anaerobic Baffle Reactor followed by an Anaerobic Filter with the outflow finally disposed into an well to facilitate ground water recharging.
Now the profound outcome is quite encouraging for him, because the rainwater from the roof of the complex and even the waste water also is not allowed to go into the storm water drainage. It seems that he would be fully dependant on the harvested rainwater and he is now very happy, because of the fact that he need not use the bore well in his campus for most of the time in the year, except for the lean period (February & March ) with scanty rainfall.
Rainwater harvesting is another highlighting necessity to counteract yet another serious community problem. Every new construction in Guwahati begins with sinking a borewell due to absence / erratic nature of public water supply. Such indiscriminate digging of borewells also results in depletion of ground water levels. The depletion of ground water levels is significant in areas which have been witnessing rapid construction activity for the last few years. Many apartments in these areas are now depending on water tankers. However, one notable fact is that the construction of the upper floors of the multistoried complex of Dr. Choudhury, was completed with the stored rainwater only.
Economics of the approach :
The approach was initiated with self financial support and the financial burden sometimes turned him skeptical about the benefits from it. But his deep interest and concern for the environmental upkeep kept him unperturbed to accomplish the same till the end. However, after its successful completion, the following economic benefits made him proud to be nicknamed as “Resident Water Manager”.
- Less dependence on the other sources of water.
- Substantive reduction on the use of the deep tube well has saved him on the energy bill.
- The construction of the upper floors of the multistoried complex was completed with the stored rain water only. So there was no expenditure for hiring charge for water vendor, which would have been necessary in the absence of such arrangements of Rain Water harvesting.
- Aesthetic and environmental impacts due to groundwater recharging and proper wastewater treatment unit.
Awareness and motivation for Others :
Such exemplary arrangements encouraged the residents from the nearby locality to follow and opt for its replication. It is quite evident that necessary supports from Government / Civic Body / Financial Institutions may ease out the financial burden to invite its acceptance in a big way.