Irrigation scheme put to the test

Press, 5 March 1982, Page 9

Irrigation scheme put to the test

The harsh, late-season drought in Canterbury has tested the W'aiau Plains Irrigation Scheme to the full and those farmers using it have benefited tremendously. According to the chairman of the Waiau Plains Farmers Committee. Mr Neil Mclntosh, the whole area would have been in a very desperate situation if the scheme had not been working. The scheme, which supplies about 80 farms and covers 17,000 hectares, was opened in November, 1980. It has cost about $ll million so far and the final cost is expected to be $24 million.

It is designed to irrigate the soils of the plains once everv 17 days, with occasional restrictions in times of low river flow.

Irrigation of the Waiau Plains was first considered in the early 1950 s and preliminary investigations were carried out by the then Ministry of Works. Interest lapsed for some years, and it was not until 1973, under the Government's new irrigation policy, that interest revived.

In January, 1974, local farmers renewed the application for a Government — sponsored irrigation scheme. In July, 1977, the Government gave financial approval to commence the scheme and construction began officially on September 30,1977. The scheme uses mainly border-dyke irrigation, al-

though there is some spray irrigation. “Those farmers who have had irrigation since the last autumn have found it a tremendous advantage,” Mr Mclntosh said. “As lamb feed ran out in January and there are no immediate prospects of winter feed, it would have been bleak without the irrigation scheme," he said. Yields from season to season are expected to be more consistent and production to double as a result of the scheme, but Mr Mclntosh said that it would be too early to assess the effects. There had been some delay with the allocation of funds, and as a result several farmers had had to wait longer than expected to be connected to the scheme, the Ministry of Works and Development water and soil engineer in charge of irrigation, Mr A. D. Stevens said. The Balmoral Irrigation Scheme is a continuation of the Waiau Scheme and construction began in November, 1981. It is intended this will supply between 25 and 28 farms, a total of about 5500 hectares.

Border-dyking will be the predominant method of irrigation with head-race systems distributing the flow around the farms and on to the pasture. About 20 per cent of the area is expected to use spray irrigation as an alternative.