Service Contract No 2007 / 147-446 Strategic ... - Swaziland

Figure 13:LUSIP irrigation canal5.2.1.7 Sugar Cane Irrigation RequirementsSugar cane is a thirsty crop and in Swaziland requires irrigation all year round to cater for itswater requirement. According to the Design Review Report (Coyne et Bellier, 2005) theannual net irrigation consumption of water by cane is calculated to be 1091 mm/yr. Thistranslates to an average annual net irrigation consumption of 0.35 l/s/ha (gross, after 7%canal losses and 75% irrigation efficiency is 0.496 l/s/ha) for 365 days/yr and 24 h/day.Irrigation systems commonly used in Swaziland for cane farming are drag line sprinklers andcentre pivot. Some commercial estates are changing to drip irrigation in order to maximisethe efficient use of the available water. Improvements in irrigation efficiencies could be madewith a review of existing systems to identify the inefficient areas and identify appropriateirrigation systems to replace existing systems (mostly sprinkler).Water allocation for sugar irrigation is based on volumetric quantities that vary according tothe crop. Cane farming is allocated 13,650 m 3 /ha. Application for irrigation water is handledby the respective River Basin Authority in which the activity is to fall. Challenges exist inwater allocations due to the limited volume of water that is unallocated. In terms of the WaterAct Section 37(9) a permit to divert or use water for agricultural or industrial purposes or for alocal authority shall require the permit holder to install and maintain adequate devices tomeasure and record the flow rate and volume of water diverted or used. The StrEA team isunsure how widespread implementation of this requirement is within the industry as efforts toobtain water use information was hampered by a lack of data.RDMU (Strategic Environmental Assessment of the National Adaptation Strategy) - Page 42