We do not have plenty of water to waste

A QUOTE by the famous American poet, W. H. Auden, "Thousands have lived without love, not one without water", aptly describes the importance of water. Water is fundamental to life; and according to the World Health Organisation, by 2025, half of the world's population will be living in water-stressed areas.
The United Nations (UN) has in recent years issued statements highlighting water scarcity and access to clean water as one of the toughest issues facing mankind. Indeed, finding solutions to clean water has become a grand challenge for engineers in the 21st century.
Since 1992, on March 22 every year, global communities celebrate "World Water Day", a day dedicated by the UN to educate people on issues surrounding water. This year's theme, "Nature for Water", aims to explore nature-based solutions to solve 21st century water challenges. It signals an opportune time for engineers to rethink how they could contribute to solving water security challenges.
So, how serious is our water problem? Despite water being the most abundant resource on earth, 97.5% of it is seawater consisting of high levels of salt. Of the remaining 2.5% of freshwater, only 0.1% is suitable for drinking. Over decades, rapid development and industrialisation has exacerbated water pollution and shortages in numerous parts of the world. A UN report revealed that 1.8 billion people will no longer have access to water by the year 2025. Access to clean drinking water, sanitation and other uses has become a critical problem. Malaysia is no exception. The recent water disruption faced by millions of Malaysian households served as a good wake up call.
As Malaysia steers towards developed nation status, economic activities, industrialisation, tourism, in particular, commencement of large-scale infrastructure projects associated with extensive drainage basin development are gathering pace. These activities lead to rising river beds, which in turn increase the likelihood of flooding and affect clean water availability. At the same time, population growth, changing water consumption behaviour and the increasing number of high density buildings are placing greater pressure on our clean water supply.
It is time now to take more proactive actions to solve our water issues as water is not a limitless resource. In addition to changing water consumption behaviour, water reuse is an easy and cost-effective approach to deal with water scarcity. Greywater is domestic wastewater discharged from the bathroom, kitchen, basin cleaning, laundry washing or from commercial buildings. Greywater is normally lightly polluted and can be treated to be reused for non-potable activities like toilet flushing and garden watering. Many are not aware that approximately 42% of drinking water in Malaysia is used for toilet flushing and garden watering. If we substitute this portion of water with treated greywater, we could save massive amounts of freshwater and help mitigate the urban water crisis.
In recent development of recycling systems, engineers are moving beyond conventional treatment technology, and looking into more natural and greener solutions for wastewater treatment. One such example is the greenwall, which utilises plants and soil as the treatment media in greywater recycling system. In the greenwall system, pollutants in greywater are consumed as fertiliser by plants and eventually in turn produce clean treated greywater, which can be reused.
On the other hand, there are recycling systems that utilise food waste as the main treatment media for greywater. In this system, food waste is collected from local vendors and converted into useful treatment materials such as membranes and absorbents. This approach provides us an alternative to low environmental impact treatment systems that could conserve water and simultaneously reduce solid waste sent for landfill.
As outlined in a report by the National Academy of Engineers, technological solutions to the world's water problems must be implemented within systems that recognise and address these inequities. As educators and engineers, we believe it is our duty to encourage more young talents to better understand critical issues facing society and help them use their creativity to solve these issues. Engineers should use their expertise and creativity to help communities leverage technology innovation to implement sustainable water resources management which extends the life cycle of water.
Mankind will not survive without clean water. Save water, save the world.
Dr. Yoon Li Wan, Dr. Oh Kai Siang and Cik Nurhazwani Ismail
Lecturers, School of Engineering,
Faculty of Built Environment, Engineering, Technology & Design
Taylor's University