Commercial premises are significant consumers of municipal water. Despite comprising only 10% of municipalities’ total customer base, offices consume almost half of all water supplied by local government. In a water-scarce country such as South Africa, it is imperative that businesses continue to focus on reducing the water footprint of commercial premises. In doing so, they also save in water costs demonstrating that quality plumbing makes sound business sense. This is enough incentive for businesses to use water judiciously.

To help save water, many enterprising businesses are harnessing the wealth of knowledge that resides within the professional plumbing industry, spanning plumbers through to manufacturers and suppliers of innovative plumbing systems. 

“Professional plumbers are at the cutting-edge of water efficiency. Considering the high demand for ‘green’ and ‘smart’ plumbing solutions in the country that is also being driven by the increasing costs of water and electricity in some cities, many plumbers have chosen to specialise in the field. They continue to keep pace with new plumbing technologies that are proving to be very effective in reducing water and energy use. These range from simple systems that have a large positive impact on water use through to sophisticated digital technologies that can even alert property owners of leaking hidden pipes on their premises so that they can take timely remedial action. This is not to mention the focus of manufacturers on designing and developing plumbing materials that last significantly longer to reduce potential leaks and maintenance costs for property owners, as well as the carbon footprint of their products. Qualified plumbers know when to recommend the use of these materials and how to correctly install them,” Brendan Reynolds, Executive Director of Institute of Plumbing of South Africa, says.

Addressing leaking plumbing is always a sound starting point when working towards reducing the water footprint of a commercial premises. Bear in mind that a leaking tap in the office kitchen or bathroom or toilet, for example, can waste up to 30l of water every hour. A qualified plumber will be able to correctly repair leaks and locate hidden faulty pipes on a commercial premises that can also run into exorbitant costs if left unchecked.

The next point of focus is usually the ablution facilities on a commercial premises. Toilet and urinal flushing, alone, use at least 43% and 20% of office-based water, respectively. When combined with washing in basins, ablution facilities can account for as much as 90% of total office water use.

Possible solutions include installing low flush toilets that only use six litres per flush. This is opposed to older toilets that use between 7,5l and as much as 13l per flush. In some instances, it may only be feasible to install water saving devices in existing cisterns as a

short- to medium-term solution. However, these interventions, alone, can save between one and three litres of water per flush.

Meanwhile, control devices can reduce urinal water use by as much as 70%. They may include timer controls that are set to match the hours that urinals are being used by staff. There are also more advanced solutions available to commercial property owners to help them reduce water demand. Qualified plumbers will be able to advise property owners as to which of these are the most suitable for their sites, as well as correctly install and maintain them. These include systems that use infra-red or ultrasound sensors that detect the presence of people and only then start supplying water. Others are triggered by variations in water pressure or flow when taps are opened in office ablution facilities.

Waterless urinals are also an option for some commercial premises. Such a system that replaces a conventional 3,7l per flush urinal can save about 150 000l of water a year. All waterless urinals work in a similar way. Urine is transferred via gravity from the basin through a seal in a cartridge and into a plumbing drain system. The seal prevents odours and sewer gasses from rising up the pipe and into the ablution facility.

Reynolds notes that a further advantage of these technologies is that they help to reduce the amount of wastewater that is released into the municipal system. This alleviates pressure on already-strained wastewater treatment works and mitigates pollution. As a result, the savings realised in reticulation and wastewater treatment costs can be spent more optimally on maintaining infrastructure and, in doing so, helping to attend to the serious sanitation challenges that the country is also facing.

Meanwhile, the office canteen can account for about 9% of total office water use. One of the contributors to high water use in the kitchen is inefficient taps. Taps used in these applications and ablution facilities for washing purposes can account for up to a third of office water use. Fitting outlet devices, such as sprays and aerators, to taps can reduce water use in these applications by as much as 80%. There are two such systems, namely atomisers and aerators. Atomisers disperse water into tiny droplets to wet larger surface areas with less water. Aerators, on the other hand, control the straightness and diameter of the streamflow and, in doing so, eliminating splash that wastes water. However, some commercial property owners prefer more sophisticated solutions to save water that is used in basins and sinks. Again, qualified plumbers will be able to provide important advice as to which of these will provide the best savings in water use. These systems include electronic sensor and timed turn-off push taps which, if properly installed and maintained by a professional plumber, prevent waste and flooding from taps that are left running.

After reducing water demand by implementing these interventions, many owners of commercial properties will augment water supply by harvesting rainwater. This “green plumbing” system has grown in popularity over the years and is, therefore, an important area of focus for many qualified plumbers in the country.

Rainwater harvesting collects and filters rainfall from the roof of buildings. Considering their size, many offices, large shopping centres, factories and warehouses provide ideal surfaces for harvesting rainwater. This water is stored in tanks and used for applications, such as flushing toilets, irrigation and cleaning, which accounts for about 1% of all office water use. A further spinoff of these systems is that they divert rainwater runoff and, in doing so, relieving pressure on severely strained municipal sewer systems. Rainwater harvesting remains an attractive proposition because of the system’s simple design and components, as well as low operating costs.

“The South African plumbing industry can play an even greater role in helping South Africa to reduce water demand as has been identified in the Department of Water and Sanitation’s Model Water Services Bylaws. Unfortunately, many municipalities are yet to implement them. Meanwhile, in the few jurisdictions where they have been put into effect, their enforcement has been lacking. This has led to an increase in the use of inferior plumbing products and substandard workmanship that has severely exacerbated our water and sanitation challenges,” Reynolds concludes.