In a rainy season such as this in Bengaluru , we hardly remember the water shortage we passed through in the recent summer and, blame civic unpreparedness for the rains flooding our streets. We seldom realise rainwater is one of the clean sources of fresh water, and let it flow out of our premises, streets and city. Rainwater can meet a large part of our requirements if harvested effectively.In a place like Bengaluru with annual rainfall of about 900 mm, it is possible to meet the entire water requirement for a four-member family in the monsoon months if the rooftop rainwater is collected in an area of just 1200 sq.ft. We have learnt this by experience. A 1000-seater office building at Infosys in Bengaluru, for example, has been able to meet about 40 per cent of its fresh water requirement during monsoon months by harvesting rooftop rainwater. There are other ways too such as percolation through soft landscape areas, recharge pits to improve ground water table and through artificial lakes.Treating wastewater is important not only from the point of its reuse, but that will help us keep our waterbodies and environment clean. The harmful effects of untreated sewage released into waterbodies are clearly visible from the state of our lakes in Bengaluru. Recycling of wastewater can be done in many ways depending on the type of waste water generated. As per our experience at Infosys, the membrane bio reactor (MBR) technology has proven to be effective for wastewater treatment of high loads (campus level) and, we are able to achieve a high quality of treated water even with low maintenance.Use of treated wastewater for different applications reduces the need for fresh water. At Infosys, treated wastewater meets most of the requirements of flushing, gardening and make up for cooling towers of air conditioning plants. The primary condition to achieve reuse of treated wastewater is having a treated water line network and buildings with dual plumbing lines – one for fresh water and the other for treated wastewater. Use of treated wastewater is the way forward to reduce our dependence on waterbodies. As a city scale example, 30 per cent of the water requirements in Singapore is met through treated wastewater.There are several methods and technologies available today to minimize water consumption in buildings. Measures like having aerators for taps, low flow faucets and showers and dual flush low water use western commodes can have a great impact on water consumption. By using efficient fixtures, the daily water consumption at Infosys office buildings has been measured at 25 litres per person, which is 45 per cent lower than the National Building Code water requirement.At Infosys campuses across India, by implementing initiatives such as the above over the last eight years, we have been able to bring down the per capita water consumption by 41 per cent. This is no rocket science , and most of these initiatives are replicable not only by corporates but by households as well. Water conservation not only enables water access to poor, but given the close link between water and economy , it will lead to a sustainable economic growth.It is time we realize the importance of this precious resource, implement measures to reduce water usage, and conserve every drop of water Bengaluru gets.(The author is a Regional Manager for Infrastructure at Infosys, Bengaluru)