Water consumption is basically divided into domestic, industry (including commercial) and agriculture use which uses 17%, 21% and 62% respectively. In addition to that, there are few industries and almost all agriculture activities uses water direct from nature and not the treated water. According to Malaysia Water Industry Guide 2010, 2.02 billion cubic meters of treated water (1 cubic meter is equivalent to 1000 liter) was consumed by domestic consumers in year 2009. Therefore, AWER estimates that industrial sector uses around 2.5 billion cubic meter of water and agriculture sector is about 7.3 billion cubic meter of water.
Wastage of water happens when an individual or entity uses water more than the needed capacity. World Health Organisation (WHO) recommends only 165 liter/capita/day for domestic consumption. This means domestic consumers can use up to 5 cubic meters a month per person. For example, if there are 5 people in a family, the sustainable water consumption should be within 25 cubic meters.
However, Malaysia Water Industry Guide 2010 report outlines that the average water consumption for domestic sector in year 2009 is 202 liter/capita/day. The highest rate is 286 liter/capita/day for domestic consumers in Penang which is close to 2 folds of recommended water consumption by WHO. On the other hand, Singapore domestic consumers are using around 155 liter/capita/day only.
The value of water wastage for industrial and agriculture sectors are difficult to estimate. This is due to differences in operational technologies and unavailability of water consumption statistics in these sectors. However, comparison between similar types of product and services can be implemented to ensure water efficiency.
The source of water wastage is focused at our habit and technology used. For example, water efficient tap (water with air bubble) helps to wash away soap faster. There are individuals whom are not accustomed to such equipments and will change to non-efficient tap. Therefore, a good technology might not be used due to people’s habit.
Reuse of wastewater is also not practiced widely. This is not something new, but it is either forgotten or inconvenient. Domestic wastewater is divided into graywater and darkwater. Graywater comes from activities such as washing clothes, kitchen wastewater, bathing, etc. This wastewater can be used for non-potable use (non-drinking and non-edible). Meanwhile, the darkwater is wastewater from toilet (sewerage) and it is not suitable to be reused or recycled at home.
In average, 80% of domestic wastewater is graywater. Reuse and recycling this wastewater helps in water efficiency as well as reduce the extra 37 liter/capita/day water usage comparatively with WHO recommendation. The reuse can be easily done by using this wastewater to wash drains, toilet flushing, watering plants and other non-potable use.
For industry and agriculture sector, water efficiency means reduction or optimisation of water consumption for a particular process. This is seen as water consumption rate or better known as water footprint. Water footprint helps us to determine water consumption for many sectors. This is a better demand management and cross-cutting to all sectors. For example, we use 140 liter of water to produce 1 cup of coffee, 184 liter of water for 1kg of tomato, 1000 liter of water for 1 liter of cow milk and 20,000 liter of water to produce 1 laptop. Through these water footprint values, both industrial and agriculture sector can be more water efficient and reduce high dependency on water strategically.
AWER urges Ministry of Energy, Green Technology and Water to develop a national water efficiency framework to ensure water consumption in all sectors can be regulated and enhance its efficiency.
Prevention is better than cure.
Piarapakaran S., President, Association of Water and Energy Research Malaysia (AWER)
