Rakaia River at a crossroad

Press, 27 December 1979, Page 13

Rakaia River at a crossroad

Droughts and dryland farming might become a thing of the past for Rakaia farmers if the largest and most costly irrigation scheme proposed for Canterbury- proceeds this Go decade. The Lower Rakaia Scheme is planned to irrigate about 55.000 hectares of farm land on the south side of the Rakaia River. involving nearly 300 farmers. Water for irrigation will be taken Si|

from the Rakaia Rivet and the amount will depend on the out* come of negotiations and studies on the use of underground watet within the scheme. ovemment policy and subsidies on communal irrigation schemes do not yet extend to farm irrigation using groundwater and many farmers in the proposed irrigation district already use these systems. ignificant increases in

farm production will result from the irrigated land, but in spite of this many local fanners are doubtful that the high cost of the scheme (an estimated SSSM) can be justified. The Ministry’ of Works and Development in-

tensified planning, negotiations. and research for the Lower Rakaia Irrigation Scheme this year, and as the Government machinery gathered momentum, so interest and concern from environmental, recreational and wildlife

groups kept pace. Opposition from these groups is not to irrigation as such, but to the effects a reduced water flow will have on the Rakaia River and on the river ecology, and the use by the public. A comprehensive report on the water resources of the Rakaia River will be made public in February before farmers in the district are polled to gauge their opinion of the proposed scheme. If a majority of farmers support it the Ministry of Works and Development will apply for a water right. Submissions from all interested groups and individuals on the

water right application will be heard by a special tribunal: if approved, the first works could begin in 1981 with water available to some farms from about the middle of the decade. The first communal irrigation schemes in Canterbury were installed during the 19505. Now, more than 25 years later, only the Rakaia River remains virtually untouched. The Ashburton. Rangitata, Opihi, and Waitaki rivers to the south, and the Waimakariri, Ashley, Hurunui, and Waiau rivers to the north, all have existing or proposed communal irrigation schemes. The effects

oi these schemes have been hotly debated between the environmental and recreational groups, farmers, and developers. An issue highlighted by the Rakaia River controversy was the question of including groundwater in government policy on irrigation. Present policy only extends to subsidies for farmers using border-dyke systems in communal irrigation schemes. Many farmers have been adament that groundwater irrigation and the use of spray trrig a t i o n equipment should also come under these subsidies. Inclusion of groundwater in the Lower Rakaia scheme would

mean less ater needed from the river for irrigation purposes. Many farmers in the proposed irrigation district have invested in bores and spray irrigation equipment. Under existing policy , they' will be liable for some of the costs of capital works. although they will not benefit directly from the scheme. The Ministry of Works and Development is negotiating for the inclusion of groundwater within the scheme. It is also awaiting results of a water resources report that assessed areas of groundwater available for irrigation. The area discussed is along the banks of the

lower Rakaia and Ashburton Rivers and inland from the coast. No firm boundaries have yet been established. The report is the most extensive study of any water resource undertaken in the country. For nearly two years, scientists from the Ministry of Works and Development in Christchurch have been involved in the study. They include the hydrology systems group from the Science Centre, the irrigation section of the Water and Soil Division, and the Ministry of Agriculture and Fisheries in association with the North and South Canterbury’ Catchment Boards. As well as ground and surface w’ater investigations, the report includes background to the scheme, studies of soils, fish, wildlife, and fauna.

present and future water uses, plans for Irrigation development. quantity and effects of abstraction, and the economic effects of irrigation. The Ministry of Works and De' elopment did want to ensure that anj surface water applied for would be the minimum necessary. says the District Commissioner <>f Works. Mr P. F. Rev nolds. Amendments to Government policy on the communal irrigation schemes and the inclusion of groundwater subsidies would have tn be made by farmers through their local M.P.s," he adds. When current policy came in. it was based on the flood border-dyke irrigation system. Since 1972. major ad vances had been made in the use of spray irrigation, Mr Reynold* says.