As India continues to sustain an economic growth of 7% and above, rapid urbanization and increase in living standards are taking a heavy toll on fresh water supply. Signs of an imminent and widespread water crisis are evident. With erratic monsoon patterns, growing population and depleting groundwater stocks, the situation will only worsen in the future. Recycling and reusing of wastewater is a sustainable way for Indian cities to continue to thrive and prosper.
While sewage treatment plants offer to recycle sewage water and convert it into usable form, such systems remain far too expensive to install, operate and maintain. Majority localities in Indian cities and towns continue to rely on Municipal water for all their water needs with recycled water amounting to less than 1% of the total demand.
Greywater recycling offers a simple, cost-effective and self-sustaining way of conserving freshwater. Not only does it reduce water demand, but greywater recycling also has huge potential to solve the most basic need of underprivileged sections of the Indian society: Sanitation.
What is Greywater?
Greywater (also spelled as graywater, grey water or gray water) is the lightly-polluted domestic wastewater generated by activities such as hand/body washing, bathing and washing of clothes. When compared to domestic wastewater, greywater is minimally contaminated with lower concentrations of organics, solids, nutrients, and pathogens, rendering the water suitable for reuse with little to no treatment. Wastewater coming from toilets is blackwater or sewage.
Common sources of Greywater
Greywater is mainly a byproduct of washing and does not include toilet water.
Why recycle greywater?
As mentioned earlier, greywater is lightly polluted and may contain small traces of dirt, food, grease, hair, and certain household cleaning products. As greywater contains fewer pathogens than domestic wastewater, it is generally safer to collect, treat and reuse.