South Africa’s Nelson Mandela Bay spent much of 2022 staring down Day Zero. Dams dried up, taps ran empty, and some schools had to close by 11 am because there was no water. At a time when little rain is falling, every drop is precious – yet the local municipality’s online water dashboard showed more than 10 000 leaks being fixed between 25 June and 3 August, with hundreds more in the pipeline.

Plugging those leaks, and preserving the water that supplies Africa’s homes, farms and businesses is vital to solving the continent’s water crisis.

Leaks aren’t always easy to locate, but an emerging field of smart water-monitoring systems, supported by IoT, is helping to preserve those precious water supplies. Israeli company Asterra, for example, uses satellite technology and microwave sensors to find leaks underground, providing real-time data to enable quick responses.

Asterra worked with water-management company Suez and water-services provider South West Water in the UK to do exactly that. The result, Suez claims, is about 83 million litres of water saved daily in the UK, with more than times as many leaks found per day compared to when using traditional methods.

‘Apart from being a truly disruptive solution, this technology has unique scalability,’ says Nick Haskins, Suez business development manager. ‘One satellite image can cover 3 500 km² of land area, which translates to thousands of kilometres of pipework. One image can cover an entire water system, with leakage “hot spots” being easily identified accurately and with great precision. If acted on quickly, this would result in [fewer] damages, claims and complaints.’

If this kind of Industry 4.0 technology can help fix pipes in suburban Devon and Cornwall, could it do the same in rural Africa?

Researcher Mduduzi Mbiza and professor Saurabh Sinha of the University of Johannesburg believe so. ‘Ageing water infrastructure is one area that could use the help of 4IR technologies, particularly the internet of things,’ they write in a recent opinion piece. ‘Remote sensors, for example, can improve the accuracy and speed at which utility systems can detect and repair leaks; 3D-printing technology can produce complex water-infrastructure components, reducing costs and production time. Big data technology can assist in understanding climate change trends by detecting ecosystem changes and forecasting natural tragedies. Artificial intelligence can also reduce water wastage. Additionally, it can reduce water pollutants, simplify water management, and optimise irrigation systems in the agriculture sector.’

Edwin Sibiya, CEO of smart water meter manufacturer Lesira-Teq, agrees. In an interview with Pumps Africa, he says that smart water meters reduce wastage and costs through leak detection, timely water consumption feedback, and changing customer behaviour.

‘We have witnessed these improvements through the projects we have been involved in and remain confident that smart water meters remain a sustainable solution to the water crisis around the world,’ he says. ‘The results produced by smart water meters prove that this solution can help drought-stricken South Africa improve water consumption and save water that is carelessly lost due to water leaks and poor infrastructure.’

Agriculture is central to this. According to World Bank estimates, the sector accounts for 70% of all freshwater use. It is, by far, the thirstiest of industries.

Abdul Salam is an assistant professor at Purdue University in the US, where he is exploring the possibilities around agricultural IoT, or Ag-IoT. This involves technologies such as wireless underground communication, subsurface sensing and soil antennas, which help farmers track the conditions on their land in real-time, applying inputs such as water and fertiliser as needed.

‘In particular, monitoring conditions in the soil has great promise for helping farmers use water more efficiently,’ he writes in the Conversation. ‘Sensors can now be wirelessly integrated into irrigation systems to provide real-time awareness of soil moisture levels. Studies suggest that this strategy can reduce water demand for irrigation by anywhere from 20% to 72% without hampering daily operations on crop fields.’

Farmers have been using soil-moisture measurements to make water management and irrigation decisions for ages. ‘Automated technologies have largely replaced hand-held soil-moisture tools because it is hard to take manual soil-moisture readings in production fields in remote locations,’ Salam writes. ‘In the past decade, wireless data harvesting technologies have begun to provide real-time access to soil-moisture data, which makes for better water-management decisions. These technologies could also have many advanced IoT applications in public safety, urban infrastructure monitoring and food safety.’

However, wireless data collection comes with its challenges when you leave the lab and step out into the mud of the farmland. For example, the Purdue team has found that when the antennas that transmit sensor data are buried in soil, their operating characteristics change drastically depending on how moist the soil is. ‘Water in the soil absorbs signal energy, which weakens the signals that the system sends,’ writes Salam. ‘Denser soil also blocks signal transmission.’

As 4IR technologies mature, Ag-IoT innovators are finding creative workarounds to those practical challenges – together with solutions to other water-related problems, including (and especially) leaks.

In South Africa, the Council for Scientific and Industrial Research (CSIR) has identified Precision Agriculture as a key technology to support commercial and rural economies in the agricultural sector. Its position is that the agricultural sector needs to do more with less, by efficiently managing the land and water resources that are available. ‘Farmers face a lot of challenges, including climate variability, increased costs of farm inputs, emergence of new diseases and pests, like the armyworm, and water security issues. All these challenges impact the productivity of the crop and the profitability of running the farming operation,’ says CSIR senior researcher Sabelo Madonsela.

To that end, the CSIR has partnered with FarmSol Holdings, an agricultural services company that has seeded hundreds of emerging South African farmers, to digitally transform its maize-farming extension services using drones, satellite technologies and big data analytics.

One of those emerging farmers is Amos Njoro, who is based near Johannesburg and farms maize and soya. ‘The challenges we have as farmers is understanding and knowing exactly the challenges that lie within our land,’ he says. ‘For example, when we plant, it is the farmworkers who are driving the tractors. They go deeper into the lands. We as farmers, we look up to a certain distance. The system that the CSIR offered makes things easier for you as a farmer. From where you are sitting – even in the office – they can pick a spot right in the middle of the land and show you exactly what is happening there: shortage of application, of nitrogen or another element. You pick it up in time, and then you are able to act on time.’

It’s a hyper-localised solution that, when used alongside bigger interventions such as satellite tracking technology, is helping to improve water efficiencies and – crucially – reduce water waste across Africa’s perpetually parched farmlands.

By Mark van Dijk
Images: Gallo/Getty Images