The perennial problem of water shortage in Selangor (one of the highest populated state in Malaysia) is going to hit harder after festive season. The fasting season might have quelled the fear on possible water rationing exercise but such situation may not be the same once that period ends. Throughout the non-water rationing period, water shortage issues have never ceased to be the topic of discussion in any of the local tabloids. Various efforts on spreading water-saving awareness have also been done by concern individuals, groups and organizations. Yet, some ignorant still refuse to practice water conservation and consequently contribute to the drastic water level fall at Sungai Selangor dam (Selangor River Dam). In fact, the current drop to 36.18% is even lower than the water level recorded during last water rationing exercise (36.53%).
It is time for a change. There is a need to incorporate more water treatment technologies so as to decrease the dependency on dam water. This alternative is vital to prepare the nation for the worst and other imminent crisis especially when population is increasing day by day. Not only that, it is also the key to drive the country towards sustainable water management. Nevertheless, each of the technology has its strengths and weaknesses that the authority/government must take into account before making decision.
| Water Technology | PROs | CONs |
Water extraction from air
This concept is first discovered by James J. Reidy 20 years ago. As a matter of fact, the amount of air around the world if being condensed is equal to about 3,095 cubic miles of water. Thus, this alleviates dam water usage.
It is almost similar to a dehumidifier. A dehumidifier works in a way that as air passes over a cooled coil, condensation occurs. James realized that the water collected is as pure as normal drinking water. Ever since then, many technologies and machines with such function have been commercialized in Australia. | 1) Able to cater different water demand (from 20 to 5,000 litres per day) .
2) Equipped with activated carbon and self-sterilizing condensation chamber to filter impurities and microorganisms.
3) Require short time to produce drinkable water.
4) Make water available for on-site consumption. | 1) Water extraction efficiency is limited by atmospheric humidity.
2) Expensive machine
3) High cost of maintenance and filter replacement |
Water extraction from ocean (Desalination)
Such water treatment method involves a large water filtration plant located near ocean. Desalination is a process to obtain fresh drinking water by using salt water from sea after going through a few treatments like example, reverse osmosis.
| 1) Water supply as it is not affected by weather.
2) High quality water as it is able to remove numerous impurities.
3) Cost reduction: Locally placed plant will be able to cater water for people around it without having to build pipes and channels to obtain water from other places. | 1) High consumption of energy, resulting high GHG emission.
2) Requires large land size for plant.
3) Pollution at ocean due to emission of highly concentrated saline water and chemicals.
4) Affect marine life and food chain particularly phytoplankton and plankton. |
Water extraction from groundwater
At water level far below water table, water is extracted for consumption. The amount of water pumped out is replenished naturally through precipitation (rain) and surface water that percolate into soil and reach the aquifer (water storage). This is a process called recharge. At the same time, discharge occurs via springs, streams or wetland. Such balancing process must take place in order to ensure continuous groundwater supply.
| 1) Water is pure and free from organic matter thus require lesser cost for treatment.
2) Renewable source of water.
3) High availability especially close to point of consumption, | 1) Salt-water intrusion due to over-extraction of water.
2) Intensive water pumping affect recharge-discharge activities.
3) Contamination risk if built near urban area, agriculture and industrial area.
4) Land subsidence |
Reference Links:
http://essay.utwente.nl/58112/1/scriptie_P_Stek.pdf
http://nocamels.com/2012/02/israeli-technology-turns-air-into-drinking-s-for-military-troops/
http://www.gizmag.com/extracting-water-from-the-air/2796/
http://www.festel-capital.com/Brackish_Water.pdf
http://www.thestar.com.my/News/Nation/2014/04/01/Kelantan-looks-to-groundwater-to-keep-the-taps-running/
| 
Previous : 'Positive comes with negat...
3 Comments
Thanks for a well elaborated article on alternative water extraction technologies. It's high time that not only Malaysia , but also other nations look at alternative sustainable sources of water.
Posted 26-02-2015 16:42
Yeap, rainwater harvesting is always in the topic of discussion but face much constraints due to cost. Water has been a global issue for long. I bet not only in Malaysia. We are doing what we can here especially in spreading awareness to people.
Posted 26-02-2015 16:02
Thank you for the detailed information of the water extraction issue in Malaysia. I found that urban areas in Malaysia are so condensed with rapidly growing population. So securing water is key for the wellness and sanitation for citizens. I think harvesting rain water and not polluting the water at the first place can be the fundamental solution :)
Posted 26-02-2015 10:21