Irrigation with reduced flow

Introduction

Reduced-flow irrigation is a high-frequency gravity or surface irrigation system that has been successfully tested in the foothills of the Cauca River Valley, in areas where water is scarce, soils are shallow and have a high stone and gravel content, and the slope of the land is greater than 1%.
Research into the use of the system on sugar cane in the foothills has been co-financed in Colombia by the sugar sector and the Ministry of Agriculture and Rural Development.
The installation costs of the reduced flow irrigation system in sugar cane are low compared to the sprinkler irrigation commonly used in the foothills. The installation with PVC pipe for agricultural use reaches an approximate value of 1,650,000 Colombian pesos per hectare, including materials and labor.
In applications with reduced flow at the foot of the mountain, very low flow rates per furrow are used, between 0.1 and 0.3 liters per second, with water advance times to the end of the furrow of 20-24 hours and irrigation frequency every two weeks.
Evaluations of the use of reduced flow by alternating furrow indicate that it is possible to achieve increases in productivity of around 10% in the tonnage of cane per hectare compared to the use of sprinkler irrigation.
The advantages of the new system include low installation costs, ease of operation, the fact that it applies non-erosive flow rates per furrow, and the opportunity to increase the productivity of lands cultivated with sugar cane in the foothills, with a benefit/cost ratio of 1.5 in alternate-alternate furrow applications.
New research conducted by Cenicaña in the flat part of the Cauca River valley, in areas with less than 1% piedmont, shows great opportunities for using the system in the Colombian sugar sector.