SDG 6 for India: Key to water independence through Rooftop Rainwater Harvesting in Monsoon

Average cost for building a Rooftop Rainwater Harvesting System (RRWHS) is INR 45,000 for 10,000 litre capacity tank. A 100 sqm roof area with an average of 50cm rainfall can yield 50,000 litres of water. In doing so, one house with roof area of about 100 sqmt and an average rainfall of 50 cm can save approximately 40,000 litres of water every year through rooftop rainwater harvesting , which is sufficient to meet the needs of a family of 4-5 members by providing a year’s supply of water.

When water crisis, everyone looks towards the sky for water. This is because the groundwater is depleting very fast. The traditional wells have almost vanished while bore wells are going deeper and deeper. The global crisis for water could be assessed with the fact that ‘Clean Water and Sanitation’ has been adopted as 6^th Sustainable Development Goal (SDG) in 17 Global Goals - 2030 declared by UNDP. However, those care for rainwater in the Monsoon may become may self-sufficient in water till next rain. 

India’s huge and growing population and inefficient agricultural practices are putting a severe strain on the country’s natural resources, in particular, water which is the most vulnerable resource. Water is life to all living beings and the driving force in sustaining civilization. According to a 2018 NITI Aayog report by the Indian Government, more than 163 million Indians do not have access to clean water, 54% of India’s groundwater wells are declining and by 2020, 21 major cities (including Delhi, Bangalore and Hyderabad) are expected to run out of groundwater.  When it comes to water, there is a need to aware people to use it judiciously, whilst also taking a variety of measures to capture and conserve water as and when it falls. By building infrastructures such as check-dams, ponds, dykes and interlinking rivers along with educating farmers, households and other community members, together, we can save a lot of water. However, there is another highly efficient, cost-effective way that individuals and families, can conserve water for domestic use – it’s called a Rooftop Rainwater Harvesting System (RRWHS). 

Rainwater Harvesting is the process of collecting and storing rainwater, directly from household rooftops, for immediate or future use. Once the rainwater is collected, it has to go through a basic filtration process which removes all dust particles that might have come in contact with the water. Thereafter, this water can be used for consumption as and when required. 

This highly efficient system can easily be implemented in homes, schools, offices, societies or any other area where there is an open space on the rooftop to collect the water. In doing so, one house with a roof area of about 100 sq.m. and an average rainfall of 50 cm can save approximately 40,000 litres of water every year through rooftop rainwater harvesting, which is sufficient to meet the needs of a family of 4-5 members by providing a year’s supply of water. 

Rooftop Rainwater Harvesting is the cheapest way of accessing potable water in the remote areas of the country, as the cost for an RRWHS varies depending on the availability of local material. The need for maintenance and repair of RRWHS is also low as the structures pose no major operational challenges for the user. Only the periodic cleaning and replacement of pipes is required after 4-5 years. The system can also be adopted in urban areas, where it saves the cost of expensive treatment via water purification. 

Today, the country sits at the onset of monsoon and as per Skymet Weather Services, India will see normal rainfall this year. With an average annual rainfall that measures between 96% and 104% of a 50-year average of 89cm for the entire four-month season beginning June, a household can save enough for the entire family for their drinking and cooking needs through rooftop rainwater harvesting. This harvested water has contributed to drinking water security to drought proofing many rural households and communities. 

There is a need for every person to play a role in helping solve India’s looming water crisis.  Here’s how an average person can contribute:

 

1. Build a Rooftop Rainwater Harvesting System to conserve water for a year – A 100 sqm roof area with an average of 50cm rainfall can yield 50,000 litres of water. Considering 80% runoff, a structure of up to size 40,000 litres can be constructed. Based on the size of the terrace, the right channel pipes made of PVC or similar materials are installed with a water filter.
2. Build a Percolation Pit - A percolation pit can also be installed that increases groundwater providing a year’s supply of water through the bore wells.
3.  Contribute to building an RRWHS system in the rural community - The average cost for building an RRWHS is INR 45,000 for a 10,000 litres capacity tank. Groundwater is depleting at a very fast pace, therefore initiatives like this are needed to sustain existing drinking water sources for the long term by taking recharge measures through conservation and rainwater harvesting.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        As every single individual consumes water, people’s participation is imminent for water conservation. Therefore, there is a great need to make water conservation ‘a movement of the people by the people and for the people’. The involvement of all the stakeholders – households, industries, agriculture and service sector should also be involved in this movement because the RRWHS is the only solution and also an opportunity for multi-storey buildings, office complexes, societies and individual bungalows as well. In addition, the public-private partnership is also required at all levels. India’s ambitions to achieve Sustainable Development Goals 2030 would be achieved only if the citizens actively contribute to water harvesting and achieve self-reliance in water. The achievement of SDG 6 would be definitely a landmark for India in achieving Global Goals 2030.  

 

Ms Pearl Tiwari is the Director and CEO, Ambuja Cement Foundation (ACF). Since 2006, the ACF has experience of building 7,000 RRWHS across India.

Note: The views expressed are the personal opinions of the author.