Groundwater is not the solution to water crisis
KUALA LUMPUR (May 12): The recent water rationing in parts of Selangor, Kuala Lumpur and Putrajaya had prompted some parties to recommend the use of groundwater as backup. The groundwater resources available in the country is estimated at around 5,000 billion cubic metres and only a small percentage is being utilised. Nonetheless, for environmental activists in particular, groundwater is not the best solution to address the nation's water woes. President of Water Watch Penang, Prof Dr Chan Ngai Weng told Bernama, even if Malaysia has adequate groundwater, it should be reserved for the future. "We need to clean up our act, protect and restore rivers which supply 97 percent of our water. "Moreover, surface water from rivers cost much less to extract and treat compared with groundwater," he said. Meanwhile, President of the Association of Water and Energy Research Malaysia (AWER), S. Piarapakaran also concurred with Chan and added that there was no shortage of water resources in Malaysia but there was an inability to manage water resources prudently. "This is actually the root cause of the water woes in the country today," said Piarapakaran. Groundwater It is true that many countries rely on groundwater, but this is because that is their only option in solving water shortages. According to Piarapakaran, most of these countries, however, have the glacier system that refilled the groundwater effectively. Groundwater levels are replenished by recharge process. This means, loss of groundwater is replenished by external water resources. "In Malaysia, the recharge is through rain water. With rampant logging and clearing of virgin forest, the ability to recharge is drastically reduced," he said. Negative impact Piarapakaran who shared some of the negative impact due to groundwater extraction made reference to Jakarta and Bangkok that made use of the groundwater. "Land subsidence is a living nightmare for both cities," he said. Prof Chan also shared Piarapkaran's concern saying that groundwater extraction could be harmful to buildings and other structures. Piarapakaran, who is also an environmental engineer, stressed that extraction of groundwater could also cause movement of some dormant chemicals in the soil that might cause pollution. "There are many cases like this all over the world. We cannot take this risk," said Piarapakaran. Another problem associated with groundwater is the lowering of the water table, if this happens, those involved will have to dig deeper and deeper for water. "Given recharge of groundwater is directly related to rainfall and total forest cover in Malaysia, large-scale projects will only severely impact the environment in the long run," he said. Piarapakaran stressed lower groundwater levels during dry season would only aggravate haze problem and peat fires. This, he said, because extraction of groundwater in areas close to the forest reserves would increase the risk of forest fires during dry season. Protect the forest Piarapakaran linked water crisis with environmental protection including the forest ecosystem. He provided Bukit Larut in Taiping, Perak as an example. Taiping is amongst the wettest towns in Malaysia but suprisingly, for the first time, water rationing was imposed on the town's residents. "It was a pretty awkward situation. A lot of people think that it is sufficient to only protect the water catchment areas. "In the natural undisturbed forests, the forest itself controls 90 per cent of the local climate," he said. However, when forests are cleared to make way for development, logging and other activities, this function will be reduced drastically. "The water catchment area for Bukit Larut is 2,153 hectares. A total of 7,130 hectares were classified as forest reserves in 1910. "In 1962, an area of 2,747 hectares were gazetted as Bukit Larut Virgin Jungle Reserves," Piarapakaran cited some data obtained from Perak Water Board (LAP). According to him, some gazetted areas in Bukit Larut have been developed for tourism purposes. In addition, he said, there was a mineral water processing factory right next to the Air Kuning Dam. "In recent years, many areas around Bukit Larut were developed and the impact can be seen through changes in water flow that resulted in landslides and erosion. "These are some of the reasons why virgin forests and surrounding areas that are being used as water catchments cannot be tampered with. "Even small scale development activities could interfere with the natural flow of water and damage the structure and function of a water catchment area," explained Piarapakaran. Dam's function The recent water crisis also acts as an eye opener to members of public on the importance of the dam's function to fulfill the demand for water during the dry season. According to Piarapakaran, the time has come for a thorough review to be conducted on existing dams. Among issues that need to be studied are the suitability of the dam to function as raw water supplier, adding existing dam's capacity, desiltation and maintenance of dams to ensure design capacity is intact. The AWER president also said that the study has to consider the need to increase raw water security in Malaysia. Another area that should be included is the building of new dams with additional reserve capacity that can be gradually increased from 50 per cent to 100 percent so that the function of the dam is for long term. Importance of design Providing the Sungai Selangor Dam as an example, Piarapakaran told the writer that it supplies almost 60 per cent of the raw water to be treated and produce drinking water. The dam was completed after the country was hit by the El-Nino phenomenon in 1997-1998. "Why did the water level of the dam reach critical level so quickly? Is the dam designed to work properly? "For dam that causes high risk to water supply in Klang Valley, early warning level should be higher. This is to ensure that cloud seeding can be done in advance," he said. He felt that the early warning level should be set at 70 per cent and if the level is less than this value, cloud seeding in catchment areas should be carried out immediately. "The level of early warning for Sungai Selangor Dam should be maintained at a high level until Langat 2 plant is constructed and operating to ensure security of treated water supply. "This early warning can provide sufficient lead time for the state government to ensure adequate supply of raw water. This will also prevent similar chaotic situation that happened during the recent water shortage, " he said.
May 12, 2014 13:08 pm +08