EXPLAINER: Why reusing water is a lifeline for SA’s freshwater

South Africa has found itself in a water crisis, with no guarantee if the situation will improve, but reusing your bath and other water could provide some relief.

Rand Water environmental management services manager Dr Leslie Hoy and Water Wise coordinator Samantha Stelli are on a mission to educate South Africa on how easy it is to reuse water in the home everyday.

They warned that the country’s water demand in the domestic sector has increased 5% over the last 10 years, and within the next decade, 1% will be added to this. 

A young man pushes a wheelbarrow containing refilled bottles of water in a road towards the Bezuidenhoutville informal settlement in Adelaide on November 28, 2019. Picture: Guillem Sartorio / AFP

South Africa is seeing consistent population growth, and with that comes more people requiring fresh drinking water. Residents use around 194 litres everyday, but this can be downscaled to 71 litres using minimal interventions. 

ALSO READ: South Africans urged to save water as climate change becomes new normal

Urban water needs consume 27% of the country’s total water in major economic sectors. This is why saving water is so important for residents. Within this 27%, gardening takes up an estimated 31% to 50%.

27% may not seem like much, but it could make a significant difference when taking into account how climate change could see South Africa’s water sources drying up faster than anticipated. 

Semi-arid and vast

South Africa is a semi-arid country, with changing rainfall patterns. It is the world’s 30th driest country, and has less water available per person than even drier countries such as Namibia and Botswana. 

Hoy and Stelli explained that the country also has “high levels of evapotranspiration”, which refers to the water that evaporates and goes into the atmosphere, and uneven water distribution, which puts even more pressure on our water.

Scenarios forecast for the country when it comes to climate change involves more extreme weather events. Longer dry spells take place in dry regions, and increased floods in wet areas. 

Flooding at a bridge along the Hennops river in Centurion, 28 January 2021. Picture: Jacques Nelles

And if no attempts are made to slow down climate change, South Africa could also see hotter temperatures. 

Hoy and Stelli noted that in the current summer season, temperatures are already above normal. But still, water consumption behaviour is not changing, which means freshwater sources are under threat. 

Reusing water 

Finding other ways of consuming fresh water is a priority for South Africa. 

Hoy and Stelli said there is a scramble for alternative water sources, which are “fast becoming the main focus of business and landscapes” as our freshwater dries up. 

ALSO READ: Why the Vaal Dam doesn’t fill up after every thunderstorm

So far, a number of inventions have emerged – desalination, rainwater, harvesting, extracting groundwater, treating sewage, water recycling and reusing greywater. 

Rainwater harvesting. Image: Water Wise

Greywater saves the day 

Greywater reuse is a method of reusing water that could households save up to 70% on the water they use everyday. 

Hoy and Stelli explained that it comes from domestic and household use of water for washing, cleaning, and food preparation. It does not contain faecal matter. 

Greywater from dishwater, however, is not preferred, because it could contain oil, grease and food scraps. 

It is meant to be used for activities that do not need fresh water, such as washing down hard surfaces, flushing toilets, and watering the garden. 

Placing a bucket under your gutters and using that water to clean hard surfaces or water your garden is simple and effective. Photo: iStock

How does it work? 

Greywater renewal systems are easy and usually free to install in your home. 

One example is putting a bucket in the shower to catch fresh water while you wait for it to get warm. Another is directing your laundry water into your garden, and collecting bathwater to be reused. 

If you are worried about getting hair and other particles in the water, use an old pair of nylon stockings to filter the water. 

It is important to note that greywater should not be stored form more than one day without being treated. 

Once one begins harvesting water to be reused, this will also encourage residents to be mindful of what they put down the drain, and how environmentally-friendly the products they use are. 

Greywater wetland 

Water Wise has taken greywater a step further by developing a simple solution to treat it for use. 

The system involves constructing a horizontal manmade wetland system in a garden or urban landscape which can be adapted to suit the volume of greywater produced. Homeowners can construct these wetlands on their own.

A natural wetland. Photo: Water Wise

Greywater is passed through the wetland, where it is slowly cleaned and filtered, and released. Roots from plants in the wetland release oxygen into the greywater, which creates a hub for biological pollutant breakdowns and organic materials.

The design is meant to mimic the natural process of wetlands in nature treating water.

A manmade wetland. Photo: Water Wise

The wetland does not pool, smell, or attract water-borne pests such as mosquitos, Stelli assured. 

Hoy and Stelli recommend that water reuse “become a part of the country’s culture in all aspects of life,” because every single drop counts.

“We cannot afford to waste any more water, anywhere.”

If you would like to know more about how to construct your own wetland, click here. Visit the Water Wise website for more ideas on how to save water.

Information provided to The Citizen by Rand Water environmental management services manager Dr Leslie Hoy, Water Wise coordinator Samantha Stelli,  and Rand Water media relations manager Justice Mohale.  

For more news your way, download The Citizen’s app for iOS and Android.