MANCO 20th : Improving Irrigation Efficiency in Conserving Water Utilization

Dato’ Ir Loh Kim Mon

RPM Engineers Sdn. Bhd., Kota Damansara, Selangor

Abstract

Water is increasingly becoming a scarce natural resource due to the ever increasing water demand and the reduction in the availability of new water resources. Water demand is attributed to two main water consumption sectors, i.e. domestic and industrial (D & I) water supply and irrigation supply. D & I water demand increases with the increase in population, urbanization and industrialization. Meanwhile opening of new lands for agriculture necessitates more water demand for irrigation. Both irrigation and D & I water supplies make up of more than 95% of the total water consumption. Irrigation alone accounts for more than 80% of the water consumption. Therefore, a decrease in irrigation water demand will significantly reduce the overall water demand.

One of the ways to reduce the irrigation demand is to improve the irrigation efficiency. Irrigation efficiency is an important performance indicator and it signifies the effectiveness and prudence of water management practices in an irrigation scheme.  The current irrigation efficiency of the 9 granary areas is in the range of 40-50%, while the total annual irrigation water demand is estimated at 8,064 million m3 (MCM). Hence, an average increase of 5% of irrigation efficiency in all the granary areas would reduce the total irrigation water demand by 403.2 MCM. This is equivalent to approximately two months of total domestic water consumption for the whole country.

This paper discusses the irrigation water requirement for double cropping of paddy and the underlining factors contributing to the low irrigation efficiency in the granary areas. Ways and means to improve irrigation efficiency are proposed to help relief some of the water demand issues facing the nation.