Groundwater: Why is it important to preserve it?

KUALA LUMPUR: Buried deep below the soil surface, groundwater may be out of sight, but this natural resource is anything but out of mind.

Formed underground in the cracks and spaces in soil, sand and rock, groundwater is stored in and moves slowly through geologic formations of soil, sand and rocks called aquifers.

Almost all of the freshwater in the world is groundwater, and in the driest parts of the world it may be the only water available to the people living there.

Its vital role in maintaining the planet’s ecosystem must not be taken for granted. It needs to be properly managed and protected to ensure its sustainability.

Groundwater is divided into two categories, namely shallow aquifer (less than 200 metres deep underground) and deep aquifer (more than 200 metres deep, and usually of better quality).

In Malaysia, groundwater storage is estimated to be 5,000 billion cubic metres. However, its utilisation is still relatively low at only three per cent, according to an international science journal, Geosciences.

Explore the potential

At present, groundwater is being used as a source of drinking water in some states such as Kelantan, Terengganu, Pahang, Sabah and Sarawak. In Kelantan for example, the tube wells or known as boring wells are used for rural villagers to get their clean water supply.

Experts said the underutilisation of groundwater in Malaysia can offer a high potential for future use, which is why it is much more important to practise proper preservation, noting the need to prevent more groundwater pollution that may restrict and affect its prospective uses.

Regional Business Development Manager of Waterco Malaysia Koo Zao Cheong said groundwater usage is still uncommon in Malaysia as the nation is blessed with ample surface water resources, which is more accessible for daily usage.

Not only that, the detection and extraction of groundwater is much more complex due to different hydrogeological criteria, which requires advanced technologies and more manpower and cost to ensure the quality and sustainability of groundwater usage, he said.

“With sufficient surface water to support current water usage at the moment, it is not an urgent need for groundwater but it remains a highly potential resource in the future.

“Groundwater utilisation in the country may not be significant as of now, but it is necessary to increase its awareness among Malaysians as an effort to preserve the resource since it also supports the economy in agriculture, food industry, irrigation and much more,” he told Bernama when contacted recently.

He said groundwater in underground aquifers is the most indispensable water resource on earth because it preserves the environment and recharges surface water resources while supplying daily household water needs.

“Groundwater makes up almost all of the liquid freshwater in the world and is a valuable resource to mankind and the environment. If we do not take action to preserve groundwater from water pollution, the viability of aquifers may be endangered which in turn will induce trouble in different sectors such as public health,” he added.

Study the structures

Meanwhile, Director of River Engineering & Urban Drainage Research Centre, Universiti Sains Malaysia (USM) Prof Datuk Dr Nor Azazi Zakaria said:“We are always in desperation when the condition of a river is polluted due to human activities or natural disasters, while not realising our country has many other alternatives.”

For example, coastal reservoirs, rain harvesting systems, Atmospheric Water Generation, Desalination, the Hybrid Off-River Augmentation Storage (HORAS) system, as well as groundwater, have not been widely used.

Therefore, in addition to sustainably use these alternative sources, he said the authorities can start exploring the enormous potential of underground water sources.

“However, a detailed study needs to be done before an exploration of underground water sources is carried out to avoid any possible contamination.

“To explore the groundwater of rock aquifers, we need to make an in-depth study of the geometry (shape and size) of the aquifer, the amount of water stored in it, the quality, source and ability to supply water.

“This is because groundwater in rock aquifers is quite different from surface water and near-surface groundwater. Therefore, such exploration needs to be carried out efficiently and monitored by relevant parties to avoid issues such as soil sedimentation when taken excessively at a certain time,” he said.

He added not all rocks can be in an aquifer or groundwater storage place. It is closely related to the type, texture, and structure of the rock and the type of water flow under the surface.

Hence, there is a need for expertise of geologists and hydrogeologists to explore this water source, while geologists and geophysicists contribute knowledge and expertise in determining the location of underground water sources, he said.

Satellite images and aerial photos can also be used by geoscientists in the field of geographic information systems (GIS) to find potential zones containing underground water resources, he added.

Optimise water sources

While efforts to utilise groundwater resources need to be expanded so that they become an alternative source of national water, Nor Azazi however said the most important thing is to fully optimise the usage of the surface water as much as possible.

This is because, if groundwater is to be used, the quality of the water must be treated in the same way as surface water, but the cost of treatment for groundwater can be more expensive if it involves the presence of heavy metals, he said.

“For example, if there are heavy metals present such as Ferum (iron) in the pumped groundwater, it will affect the hardness inside of the water particles. If this happens, then the cost of water treatment increases and the construction of water treatment plants will also increase.

“Therefore, I would like to propose a by-law under the Ministry of Housing and Local Government (KPKT) so that new housing schemes can adopt the use of rainwater harvesting systems (SPAH). In addition, the dual pipe system for potable water and non-potable water should be emphasised for domestic use.

“For example, the use of non-potable water such as washing cars, watering flower plants, washing floors, and so on does not need to be wasted by using treated water. The use of above-ground water is best used before we emphasise the use of groundwater (aquifer),” he opined.

Reduce the harm

Meanwhile, Cheong expressed concerns over daily habits that may incur unwanted groundwater contamination which can drain the aquifers faster than natural systems can replenish them.

Once an aquifer is dry, it is often lost forever as a source of water.

Not only that, there is a general belief that the harsher the chemicals, the better it is for the environment but the reality is, it is not working in that way.

Hence, he suggested a few ways to reduce harm on groundwater such as reducing household chemical use or opt for natural cleaning products whenever we can.

“The typical misconception about this is harsh chemicals can make your bathroom tiles shinier but it is actually at the cost of the environment. Instead, try to use natural household items such as lemon juice, baking soda, and vinegar since it can make up for great cleaning too. Not only are they environmentally-friendly but they also do not break the bank.

“For the green thumbs out there, try to limit the use of pesticides or fertilisers while tending your garden. Only choose safe and non-toxic biodegradable ingredients that don’t adversely affect nature,” he said. — Bernama