Suitability of land for irrigation in the Manuherikia Valley, Central Otago, New Zealand

An area of approximately 38 000 ha, covering the irrigable sections of the Manuherikia Valley, was examined to determine the relative suitabilities of individual soils for irrigation. The report discusses the physical characteristics of the soils and the other land factors of topography and drainage which are likely to affect irrigation. Three classes of irrigation suitability, further subdivided into irrigation suitability subclass units, are shown on the accompanying map and discussed in the text. A small portion of the area surveyed (5.4%) is in Class 3, moderately suitable for irrigation, 73.6% in Class 4, marginally suitable for irrigation and 21 % in Class 5, least suitable for irrigation.