Harvesting rain to save water

We are encouraged to recycle just about everything these days, however with 18% of the world not having access to clean drinking water and with South Africa ranked the thirtieth driest country in the world, one of the most important resources we should consider recycling, is water. The aim of national water week from 16-22 March is increased awareness about the challenges facing our finite water resources and the sustainable management of water levels. Harvesting rainwater and grey water is a viable method of water conservation that not only reduces your carbon footprint but your monthly water bill too. I met eco-urbanite Jane Griffiths, author of Jane’s Delicious Garden, who harvests rain water and grey water and found out how she does it.

Harvesting rain water

Rain is a free source of water, recycling rain water is not as arduous a task as it may first appear and can be achieved elegantly and efficiently in your own backyard. This was demonstrated through a guided tour of Griffiths’ garden, her sagacious garden is maintained with harvested water.  “I had JoJo Tanks installed to harvest rainwater, 1mm of rainfall on one square meter of roof will supply 1 litre of water,” she said.

Grey water tank in Griffiths' backyard

With five rainwater tanks each with a 750litre capacity, her garden is proof that the tanks can be encompassed into your environment seamlessly and effectively. “I have a large roof and all those litres which were washing away down the storm water drain are now saved in my tanks and I can use it to water the garden or wash the car. In summer, when the tanks start overflowing from all the rain, I empty it into my natural swimming pond.”

Rain water tanks in Griffiths' driveway

Rain and grey water specialist Patrick Rosslee from JoJo Tanks warned against drinking unfiltered rainwater. “Remember that untreated water is unsafe to drink. If your installer has placed the correct filters in place, and you have followed the maintenance regime correctly, this water should be safe to drink. If you do not have a water filtration system in place and need to drink this water in an emergency, we recommend boiling the water and keeping it at a rolling boil for at least a minute before drinking. If you’d like to regularly use your rainwater for drinking purposes please consult an installer with experience in installing water filtration systems.”

Grey water harvesting

Grey water is water from showers, laundry, baths and hand washbasins. It should not be confused with black water, sometimes referred to as sewage, which is waste water from toilets and dishwashers.

Rod Cairns managing director of JoJo Tanks simplified grey water harvesting for the average household. “For the average family, close to 90 percent of grey water leaves the household as waste water yet it could have been recycled and reused to water gardens, wash cars and flush toilets among other things,” said Cairns. 

He explained that grey water decomposed very quickly and had to be used within 24 hours or it would become black water, which smelt bad and could not be used due to all the harmful bacteria and pathogens.

“The simplest grey water system consists of gravity feeding water to an underground sump where it passes through a macro filter to remove hair fluff and lint. The water is then immediately pumped or drip-irrigated into the garden."

With the number of waste water management systems on the market you really are spoiled for choice when it comes to water recycling options that are effective and aesthetically non-invasive but reducing your water usage should always be the priority. Ultimately water conservation will not only have a big impact on the planet but on your wallet too.