A management study of irrigation farming in the Ashburton-Lyndhurst scheme of Mid-Canterbury

Abstract

Throughout the world, irrigation is used to raise the productive capacity of the soil, where soil moisture is a limiting factor. Many irrigation areas can not achieve any production without the supplementation of soil moisture, while others employ irrigation as a profitable means of boosting the normal production level. In 1935, the Government began the installation of a flood irrigation scheme in an area of 64,000 acres now known as the Ashburton-Lyndhurst Irrigation Scheme. The carrying capacity of the land in its then natural state was approximately one ewe per acre, and irrigation appeared to be the most obvious means of raising production levels. The terrain was suitable for flood irrigation, and a good supply of water existed in the snowfed rivers that dissected the Plain. The scheme was to be administered by the Ministry of Works, who contracted to provide water to those farmers who signed agreements. The Lands and Survey Department embarked on the development of substantial areas for irrigation, and private farmers were urged to do likewise. In 1948 and 1958, two additional irrigation schemes in Mid-Canterbury were opened. In 1963, the long standing water agreements were due for revision, and since the then ruling charges for water were insufficient to meet the operation and maintenance costs of the schemes, a substantial increase in these charges was expected. In addition, many farmers held the view that irrigation was uneconomic at the existing rates. Consequently, a body of farmers known as the Irrigation Development Association requested the Farm Management Department of Lincoln College to compare the relative profitability of dry-land and irrigation farming, within the A.L.I.S. The I.D.A. intended to use the results in their negotiations with the Government over the new water rates. The results of the survey indicated that after due allowances had been made for differences in farm size, the irrigation farmers of the A.L.I.S. were not showing greater profits than their dry-land counterparts, and in many cases appeared to be earning less. These results pointed to the need for further research into the following aspects of irrigation economics:- (1) Given an historical investment in irrigation, (a) were there any clear reasons for the low profits on many irrigation farms? (b) if so, could the management of these farms be improved, and their profits increased? (2) Given a potential for irrigation development and expansion, (a) should a farmer invest his capital in irrigation, or dry-land, development? (b) should the Government pursue its policy of promoting and financing the development of irrigation? This study is only concerned with aspects of irrigation farm management on properties already developed for irrigation. Moreover, it specifically refers to irrigation within the A.L.I.S. and therefore any conclusions reached do not necessarily apply to other schemes.