Harvested rainwater reduces dependence on river water or groundwater.
DH Photo
In a normal year, Bengaluru receives copious rainfall, often resulting in flooded roads, but 90% of this water goes waste, flowing into the drains. As the city stares at a drinking water scarcity due to the failure of the monsoon, experts estimate that only about 10% of households have implemented rainwater harvesting (RWH). In 2011, the government mandated RWH for new houses built on plots 60x40 feet or larger. In 2021, RWH was made mandatory for new constructions on 30x40 feet sites. The rule for 60x40 ft and larger plots was enforced retrospectively.
Even in households which have implemented RWH, the water is directed to the recharge pit, which no doubt is good because it increases the groundwater level. However, creating provisions like tanks to store the water will help meet at least a part of the household needs, reducing the dependence on Cauvery water being supplied by the Bengaluru Water Supply and Sewerage Board (BWSSB). Thus, the solution lies not just in adopting RWH, but also in utilising the water that is collected. According to BWSSB officers, many residents are still not prepared to accept that rainwater can be used for all non-potable purposes. While they instal RWH systems to comply with the law, many tend to direct the harvested rainwater to stormwater drains. The board estimates that even if 50% of rainfall is harvested, it will yield additional water to the tune of 10-15 TMC.
Data from BWSSB shows that only 1.8 lakh out of the 19 lakh eligible properties in Bengaluru have installed RWH systems. The BWSSB says penalising non-complying households has had little impact. The board collects nearly Rs 1 crore in fines every month, but households would rather pay the fine than install the RWH system. Bengaluru does not have a perennial source of water and has been depending on Cauvery water since 1972. With the availability of potable water fast depleting, the need of the hour is conservation and harvesting. Even at present, several new extensions do not have access to Cauvery water and are forced to make their own arrangements to meet their demands either through tankers or borewells. The couldn’t-care-less attitude of many Bengalureans regarding RWH is unfortunate. Unless there is a change in mindset, the city could soon be facing a major water crisis. The government should look beyond merely collecting fines and should consider disconnecting piped water supply to buildings, especially apartments, that do not implement RWH. Allowing precious water to go waste, especially when the city does not have its own source, is nothing short of criminal.