Smart water meters in South African schools drive down water wastage, saving millions of Rands

Giving teaching staff regular, detailed information about a school’s hour-by-hour water readings through the use of a smart water meter can bring greater vigilance to a school’s water use, and help identify leaks. The result is improved maintenance, more water-wise behaviour, and a significant saving in water bills.

In a smart water meter pilot project, which ran across four schools in the Western Cape in 2017 when the Cape Town drought was reaching its peak, the average monthly savings was enough to pay another staff member’s monthly salary.

This is the finding of a team of behavioural economists and engineering researchers from the University of Cape Town’s Environmental Policy Research Unity (EPRU) and Stellenbosch University, together with Stellenbosch-based tech startup company Bridgiot, who ran a study in 2017 to measure the impact of rolling out smart water meter and behavioural ‘nudging’ experiments in a number of schools in Cape Town.

Following the success of the pilot programme, researchers expanded the Smart Water Meter Challenge into 345 schools in and around the city in 2018. The estimated total savings across the campaign, which is still running, has reached 485 megalitres across the schools, according to tech company Bridgiot.

The project started with the installation of smart water meters designed by Bridgiot, which was founded by electrical engineer Prof Thinus Booysen from Stellenbosch University, and repairs done on leaks and burst pipes so that the schools could immediately cut down on water losses. This maintenance campaign was funded by Shoprite and the Western Cape Departments of the Premier and Education, with other corporate funders coming on board to help pay for the maintenance in individual schools.

The research team, headed by EPRU director Prof Martine Visser along with environmental and behavioural economists Johanna Brühl and Kenneth Berger used information supplied by Booysen’s smart water meters, then ran ‘green nudging’ experiments across 120 of the participating schools. This involved targeted information campaigns and inter-school competitions, where they shared useful information related to the water meter readings with the staff, to see if this could nudge the schools towards more water-savvy behaviour. The behavioural insights team at the Western Cape Government’s Department of the Premier assisted the researchers with rolling out the campaigns and helped with access to the Department of Education.

After six months, the Smart Water Meter Challenge saw a significant drop in water use, partly in response to the fact that the smart water meters campaign allowed the schools to know what their daily water readings were.

‘Normally, schools only track their water use according to their monthly utility bills,’ explains Kenneth Berger. ‘Once we installed the smart water meters, we were able to monitor the schools’ water use, down to every ten minutes.’

According to Berger, who wrote his Masters dissertation on the project, a school’s water use typically peaks during school hours. But if there is unusually high usage outside of school hours, this generally indicates that there is a leak somewhere in the system. With the level of detailed information coming from the smart meters, schools could quickly see if there were leaks that needed repair. In the case where leaks might be hard to find, staff would know to shut off the school’s water mains at the end of each teaching day.

EPRU’s team used two different campaigns in the participating schools, to see if the information from the smart water meters would ‘nudge’ schools to be more thrifty in their water use.

One group of schools received a summary of their water readings in a weekly email and text message sent to the staff. This gave an hour-by-hour breakdown of the previous week’s water use, presented in the form of a ‘heat map’, where the amount of water used during different hours of the day was marked with lighter blue for low-use and darker blue for high-use.

With the second group of schools, staff got the same weekly messages from the water meter readings but were included in a water use competition. They were shown where their water use ranked in a comparative list of other schools in the competition, and told that the school which reduced their water use the most would win a prize. This added a competitive edge.

Visser and team compared how these two groups of schools’ water behaviour measured up against a ‘control’ group of schools - schools which had water meters installed but where the staff did not receive meter reading information and were not part of the competition.

‘The results are remarkable,’ says Visser. ‘Schools in both groups that were part of the campaigns reduced their average consumption by 15 to 26 percent. We found that the schools who only received the information feedback were particularly vigilant in curbing their after-hours use, by over 50 percent. This suggests that staff personally took on the responsibility of conserving water, through proactive behaviour such as closing taps that may have been left running, or dealing with leaks speedily.’

Those schools that were part of the inter-school competition performed best during the daytime hours, when water use in schools is typically highest.

‘This indicates that the competitive element encouraged pupils to also take part in efforts to be water-wise,’ says Visser.

While the biggest water savings resulting from the Smart Water Meter Challenge were due to maintenance and repairs, the combination of smart meter information and the green nudging campaigns also lead to remarkable improvements in water use, say the researchers. When considering the water saved across the entire project at all 345 schools a total investment of R10.5 million produced a massive saving of R39 million. This return on investment points to the dramatic gains that can be made from scaling these interventions. Scaling to all schools in South Africa is estimated to provide a return on investment of R1.5 billion in the first year - enough to employ an additional staff member at every second school in the country.

There are important lessons for policymakers, according to Ammaarah Martinus from the Department of the Premier in the Western Cape Government. Firstly, the maintenance drive allowed the team to establish where the big water use was on the properties, so that repair crews could fix leaks and the schools could immediately benefit from the substantial savings. Secondly, the research focus allowed for information to be fed back to the infrastructure section at the provincial Department of Education for future action and monitoring. Through the maintenance support given to the schools, they could see the direct benefits of detecting and fixing leaks on their premises. The money saved through lower water bills meant that schools could put that money back into the school for other maintenance or school needs.

According to researchers on the project, the combined approach of investing money in smart water meters and in maintenance, as well as behavioural interventions like these kinds of information campaigns, are a sure-fire way for schools to save in the long term, because of the impact on their annual water bills.


The winners of this groundbreaking water-saving competition in Western Cape schools will be announced at a prize giving in Bishop Lavis, Cape Town, on Tuesday 3 September. Western Cape Premier Alan Winde and Western Cape provincial Minister of Education Debbie Schäfer will announce the winning schools. The competition resulted in water-wise behaviour change in 2018 that reduced participating schools’ utility bills by millions of Rands, an incentive which could result in similar water conservation measures becoming the social norm in schools.

Venue: Nooitgedacht Primary School, Heilbot Road, Bishop Lavis

Time: 8:30am to 9:30am 

Contact Ammaarah Martinus on 083 775 4583 or Cameron Cyster on 076 914 4116 in the Western Cape Department of the Premier for any further enquiries.

The full draft research paper can be viewed online at:

For more information on the #SmartWaterMeterChallenge, visit

This research was funded by the Environment for Development (EfD) initiative and the Western Cape Education Department. Various corporate partners donated to assist individual schools with maintenance.

Produced by the Environmental Policy Research Unit, School of Economics, University of Cape Town.

News | 2 September 2019