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Monday March 3, 2014 MYT 12:00:00 AM
Monday March 3, 2014 MYT 7:26:25 AM
by lim chia ying
Contractors digging a well in Balakong. There is water in the ground but there is the risk of contamination, cost of treatment processes and the possibility of land subsidence to consider before it can be pumped out. - Filepic
If there is available water underground, shouldn’t the Government make use of this water source to provide for the people?
The hot spell, which shows no sign of abating anytime soon, has taken a toll on our water supply – water levels at the Sungai Selangor dam in Kuala Kubu Baru has dropped to below 50%.
The state government has been forced to ration water supply in parts of the state.
In the meantime, the Energy, Green Technology and Water Ministry is mulling the idea of extracting underground water as an alternative source of water supply.
The groundwater idea is not something new; Selangor Mentri Besar Tan Sri Khalid Ibrahim had talked about it before. It has been said that we should reduce our dependence on surface water – which currently accounts for 98% of water consumed – since it can be easily affected by extreme weather conditions.
In some countries, siphoning groundwater is the norm. In Malaysia, Kelantan is one state that uses groundwater more than the others. In 2009, Sime Darby Water Resources had launched a groundwater project in Batang Padang, Perak, in the faith that it will offer a more reliable and sustainable source of water if extracted correctly with appropriate technology. The project, meant to distribute water to the state and even Selangor, has since been discontinued.
Malaysian Water Association (MWA) secretary-general Mohmad Asari Daud says groundwater is well-established as a reliable source of water overseas, with high levels of utilisation in countries such as Denmark (99%), Austria (98%), Switzerland (83%) and Thailand (80%).
In Malaysia, he says there is potential to use groundwater but it has to undergo treatment processes first because of the high iron and manganese content and the possibility of chemical pollution.
“The water is suitable for human consumption, only that it must be analysed for a number of parameters like physical, chemical, biological, radioactive and heavy metals. Water treatment processes can be ascertained to reach the required drinking water standards.
“What’s important is that whichever source is chosen, the quantity and quality aspects of the water source must be addressed,” says Mohamad Asari, a water engineer for 30 years. He had previously researched groundwater feasibilities in different areas of the country as well as abroad.
Despite noting some demerits (groundwater quality can differ between sampling points and adjacent areas, and over-extraction might cause settlement of structures), Mohmad Asari is positive of the advantages of groundwater. For one, it usually does not contain suspended particles that cause water turbidity. It is also less susceptible to saltwater intrusion and is a reliable resource during droughts due to the large storage.
“The source can be tapped where it is needed, on a stage-by-stage basis, and is less affected
by catastrophic events. It requires simpler treatment for usage
compared to surface water,”
says Mohamad Asari.
On the other hand, Association of Water and Energy Research Malaysia president S. Piarapakaran is not buying claims of groundwater being environment-friendly. He says some countries rely on groundwater because that is the only option to solve their water scarcity.
“Many have a glacier system that feeds groundwater effectively. As for Malaysia, the recharge of underground water is directly from rain. With the loss of forest cover, this ability to recharge is reduced. There is no water shortage in Malaysia, only the inability to manage water resources. That is the cause of the problem.”
Piarapakaran does not think that tapping groundwater should be given a priority.
“When we can still manage with surface water, why rush to groundwater? It seems like we are failing to manage surface water and running to another option. If we want to extract groundwater in a large-scale, we need to carry out detailed studies.”
He explains that there are two types of aquifers. Non-confined aquifers have high exposure to pollutants from the topsoil and the soil itself, and are prone to substantial declines during the dry season. Confined aquifers, meanwhile, have very small land areas to recharge the groundwater.
“All these pose immediate risk to groundwater supplies,” he says.
Piarapakaran also raises questions over management of groundwater sources: “Who is measuring what exactly is extracted? And who audits the sustainability of extracting groundwater? I know of a famous mineral water bottling company extracting groundwater metres away from a drinking water dam in northern Peninsular Malaysia. The question is, are they extracting groundwater or water from the dam that has seeped into the soil?”
He believes that the Langat 2 water treatment plant is more cost-effective and reliable for water supply compared with groundwater extraction.
“The largest groundwater project that was proposed (Sime Darby’s) will produce some 30 million litres per day. This project was planned by a local multinational company but information was lacking. Langat 2’s capacity is about 1,200 million litres per day, which means 40 groundwater plants are needed to carry out the function of the Langat 2 plant. It’s a huge cost as you need to get Environment Impact Assessments done, secure large areas to extract groundwater and scan water tables in the areas.
“Furthermore, all water that is extracted via groundwater still needs treatment and testing for chemicals present in the water. If, for instance, this groundwater project is close to agricultural land, pesticide, herbicide and fertilisers are potential pollutants and need to be monitored closely as the dilution effect in groundwater is very low. All these are costs to water treatment which will be added to water tariffs.”
Piarapakaran says the disadvantages of harnessing groundwater are too obvious to ignore. He points to how Jakarta and Bangkok, which use a lot of groundwater, are facing land subsidence.
He also says that when groundwater is extracted, some dormant chemicals might be stirred up, possibly leading to contamination. Drops in water tables will also cause everyone to dig deeper, he adds.
Even though Kelantan is a model state for groundwater utilisation, Piarapakaran is not convinced. He argues that if dams and water catchment areas in the state are maintained, there will be no need to use groundwater in the first place.
Tags / Keywords:
Environment, Ground water, Sungai Selangor dam, Malaysian Water Association, viable, Association of Water and Energy Research Malaysia, Kelantan, quality
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