IRRIGATING SUGARCANE WITH VERY LOW FURROW INFLOW RATES

SPRINKLER irrigation of sugarcane is a common practice at the foothills of the Cauca river valley of Colombia. Energy costs are limiting the use of this irrigation system and alternative ways of irrigation using small surface springs is under evaluation. Water is applied by gravity using small furrow inflow rates in the range of 0.1 to 0.3 L/s while furrow irrigation of sugarcane on the flat areas uses inflow rates above 5 L/s. Water is diverted from the small streams and conducted to the fields using small hydraulics heads (less than 10 m). Cheap pipelines of 100 mm diameter, made of recycled polyethylene bags, are used to conduct the water at low pressure heads to the fields where water is applied to the furrows using plastic tubing of 6 to 16 mm in diameter. Furrow lengths of 100 to 120 m with slopes above 1% are irrigated during the advance phase in 20 to 24 hours applying water depths in the range of 100 to 130 mm. Cane yields in the order of 84 t/ha were obtained, which compare very well with the production of the sprinkle-irrigated plots.