SEJARAH PENGAIRAN DAN SALIRAN
Irrigation in Malaysia is synonymous with rice cultivation. In fact, it has been quoted that irrigation in this country is only for a single type of crop, that is paddy. The reason for this is that in Malaysia, the large-scale non-paddy crop cultivation are mainly rubber and oil palm. These industrial crops do not require irrigation.Non-paddy crops requiring irrigation are the short-term types such as vegetables and tobacco. Their total planted area is very small compared to paddy and the industrial crops. The irrigation water requirement for these short-term crops also relatively small and more to supplement supply during dry spells or during the hot dry days. Its development has always been on the initiatives of the individualfarmers. For a long time irrigation for non-paddy crop remained as a simple technology. This is because the farm and plot sizes are small and could be irrigated manually.
It is not until the end of the 1980s when commercial farming began to be more widespread that non-paddy irrigation development came to be of interest in Malaysia.During this period too the Government introduced the cropdiversification policy for paddy areas and thus generated more non-paddy irrigation development. Apart from the traditional surface flow irrigation methods, there are now more areas applying micro-irrigation and sprinkler technologies for commercial fruit farms, vegetables and flowers. Its development is still private sector driven with the Government providing research, extension as well as water resources development support. Compared to paddy irrigation, nonpaddy irrigation is still considered at being in its initial development stages and has yet to record a history of its own.
Irrigation for paddy (specifically wet paddy) however, has a very long and established history in this country. It has, and will continue to, provided a significant impact on the Nation’s social and economic development. Rice is the staple food for the population of Malaysia and history has shown that irrigation development and management are the successful strategies to ensure a comfortable level of food security for the country. Irrigation is necessary for, although the average annual rainfall is more than 2500 mm, rice is a crop that requires large volumes of water over a short time to saturate the lands for planting and subsequently to maintain a standing depth of water for most part of its growth stage. Depending entirely on rainfall for water is risky since there will be days without rain and occurrences of drought. Irrigation therefore reduces this risk, improves chances of successful planting in a season and more important, increases farmers’ confidence to continue planting season after season.
Irrigation in Malaysia also has its unique definition. The broad technical definition of irrigation is “supplying and managing water for crop production” and this remains the same throughout the history. However, in addition to this, “irrigation” in Malaysia is also taken to mean only those paddy schemes that has been provided with irrigation infrastructure and subsequently wholly operated and maintained by the Government. This is an “implicit” definition and developed from the 1800s onwards when the Government decided to undertake these responsibilities as well as to introduce a law (the Irrigation Act) specifically for the management of these schemes.
Other paddy schemes are hence designated as “rain-fed” areas. These areas do have basic irrigation infrastructure and thus, technically, are “irrigated”. However, with only basic irrigation components, these areas are more dependent on rainfall than irrigation. The Government provides extension services to these areas and minimal development, operations and maintenance fund.
For the reasons forwarded earlier, this book focuses on irrigation for paddy only. It is not meant to be comprehensive. Indeed it cannot be, as history also requires evidence and records. These are not readily available for all instances and for all the States in Malaysia. Therefore, this book can only be referred to as a simplified description of irrigation development since the early days and up to present times and to provide as a quick reference for both irrigation engineers as well as the general reader.
This history is presented in a series of “themes” of irrigation development over the years. The theme is not necessarily confined to within that particular period but rather, it is considered the most significant for that particular period.
It is interesting to note that over the last 200 years, irrigation development for paddy in Malaysia extended well beyond the confines of on-farm boundaries. It has also enriched the nation’s engineering knowledge and skills in the field of managing small and large volumes of water in the country. This is because irrigation development for paddy requires planning, design, construction and management for the reclamation of large areas of lands, coastal protection bunds, structures for drainage and control of saltwater intrusions, river conservancy and flood management as well as development of dams, reservoirs and pumping systems. Irrigation for paddy also requires an understanding of on-farm water management and the need to work closely with the farmers and other Government agencies. Most important though is that irrigation development and management has ensured a stable rice supply and exceeded the nation’s rice self-sufficiency targets of 60% continuously over the last 75 years.