Malaysia is blessed with the abundant rainfall feeding our rivers and water catchments.
Peninsular Malaysia alone, receives an average of 2400mm rainfall annually while Sabah and Sarawak receives 2360mm and 3830mm of annual rainfall respectively.
Unfortunately unsustainable land use and development, increasing and unsustainable water consumption and increasing levels of pollution in our country, have made access to clean and safe water supply a tremendous challenge to overcome.
Rapid development, urbanisation, industrialisation and agricultural development aggravates the situation.
Access to clean and safe water supply could be due to several reasons and among them are:
1. lack of rain, erratic /unpredictable weather patterns
2. lack of catchments due to poor management of land development
3. increased pollution
4. unsustainable use - for example using treated water for non-potable purposes
Malaysians are a wasteful lot in many ways. A survey by the Federation of Malaysian Consumers Associations (Fomca) in 2006 indicates that although almost 90 percent recognise the importance of recycling, only 5 percent actually recycle.
About 95 percent are not aware of the energy efficiency label. Another survey by Fomca on water consumption indicates that while almost 80 percent of those surveyed are well aware of the water problems in Malaysia, the majority of the respondents are not likely to conserve water within the next three years.
One way of realising about 26 percent of our water consumption for potable use is by using alternative supply of water for toilets - namely for flushing. A study of the United States Environmental Protection Agency (USEPA) states that 26 percent of household water is used for toilet flushing.
Studies in Malaysia and many other countries have shown that harvesting rainwater or using grey water meets this objective, thus releasing precious treated water for potable use.
A lot of research has been done on rainwater harvesting and many guidelines have been developed such as the Urban Stormwater Management Manual for Malaysia (2001) and also the Guidelines for Installing a Rainwater Collection and Utilisation System (1999).
Normally, rainwater is collected directly through roofs and also other purpose built catchments.
Archeological evidence shown that capturing of rainwater dates back as far as 6000 years ago.
But technologies in water treatment and supply systems has resulted in this age old but sustainable way of using water ignored or forgotten.
Based on research and studies done, rainwater harvesting can effectively reduce the water bill by 20-30 percent in some cases up to 60 percent.
Imagine the amount of money and water which can be saved if the whole country implements this.
Instead of using rainwater, we are using treated water to wash cars, flush toilets, water plants and also for irrigation. This is such a waste when some countries such as in Africa, people are struggling to get a mouthful of clean water.
Decades of unsustainable development has lead to what experts term as a humanitarian crisis due to global warming and climate change.
Erratic weather results in unpredictable rainfall pattern and Malaysia has experienced unexpected prolonged droughts recently in Sarawak and Sabah.
This has caused water stress in these states.
Indeed a water crisis is predicted in Selangor in a few years and it could be forced to buy raw water from neighboring states.
This could be averted if more potable water was freed from non-potable use.
But in Malaysia, there are several factors posing obstacles for implementation and development of rainwater harvesting system. The first factor is with the copious amount of rainfall, people think that Malaysia has rich water resources.
Second, the frequent flooding gives impression that it is unnecessary to harvest rainfall.
Third, a single approach in managing water supply i.e. Water Demand Management instead of Integrated Water Demand Management.
Fourth, low water tariffs make it uneconomical to install rainwater mechanisms.
Fifth, lack of incentives to include rainwater harvesting in building design. Last but not least, lack of mandatory regulation to enforce rainwater harvesting system for both commercial and domestic buildings.
With these obstacles removed, rainwater harvesting would save consumers and the water supply service providers a lot of money and resources.
But rainwater harvesting system is not the answer to our water woes. Preventing pollution of water sources and catchments are of utmost importance to protect our water supply for current and future generations.