Strategies to Enhance Water Demand Management in Malaysia
CHAPTER 4: IMPLEMENTING WATER DEMAND MANAGEMENT STRATEGIES 4.1 Implementing WDM Strategies WDM is about water savings and increasing water use efficiency. Traditionally, it is confined to the major consumptive and non-consumptive water users. There are no standard and specific definitions of consumptive and non-consumptive water use in Malaysia. Several attempts have been made to obtain a consensus amongst international water organisations and practitioners (Christ Perry; pers comm.) to account for the changes and concern on water use and climate change impact and adaptation needs. For some, water “losses” through evapotranspiration is the only “consumptive” component of water use since the remainder is still usable for other demands. China is one of the countries that adopts this definition in developing irrigation systems. There are some that opt to define consumptive water as “the volume diverted away from an existing system and not returned to the same system for further use downstream irrespective of the returned water quality”. In this case, water resources development that transfers water into another basin and not returned to the original basin is categorised as for consumptive use with respect of the source basin. The traditional and widely accepted “definition” in Malaysia and elsewhere is that consumptive water use is for human activities with elements of “consumption” such as for domestic and industrial water supply, irrigation and livestock and for ecosystem. Water for hydropower and aquaculture/fishery are categorised 22
as non-consumptive. In addition, the waterbased activities within the tourism sector are also categorised in a similarly way. This chapter is confined to the following major consumptive and non-consumptive users of water, the conceptual sectoral connectivity of the WDM Strategies and Masterplan (see box below). References have been made when reviewing some relevant recent studies and reports notably Sarawak (SIWRM Study, 2009), NWRS (2012), SPAN Performance Report 2014 and MWIG 2015. Consumptive Water Use Sectors 4.2 Water Supply and Sewerage Services WDM 4.3 Agriculture WDM 4.4 Ecosystem WDM (Environmental needs) Non-Consumptive Water Use Sectors 4.5 Hydropower WDM 4.6 Navigation WDM 4.7 Recreational WDM 4.8 Inter Sector WDM 4.9 WDM Strategies and Masterplan