MONEY TO BE EARMARKED FOR ANGLING INTERESTS

Press, 5 July 1978, Page 21

MONEY TO BE EARMARKED FOR ANGLING INTERESTS

Denise McNabb A unique feature of the Rakaia hydro proposal is the agreement of those involved to set aside one per cent of the capital cost to compensate for the effect on fish. The money will be used to provide hatchery facilities which would produce one million salmon smolts, and to screen the

dam’s intake structure so that smolts cannot get in. The report also recommends that anglers be granted access along the main raceways, and that a compensatory flow be spilled into the Hororata and Selwyn Rivers to provide a continous flow downstream into Lake Ellesmere. Mr W. J. McKillop, chairman of the

Canterbury Acclimatisation Society says the compensations mark a very important stage in salmon fishery. Achievement of the levy was the clima:: of many years of hard fighting, and more often than not disappointment for a group of men dedicated to the recreational interests of the smaller rivers. These rivers are rapidly becoming infiltrated by dams to cater for the ever ir creasing need for electricity. To back up their fight these men had plenty of evidence of careless eradication of salmon populations in the past. In March, 1975, Mr D. J. Hughey, then president of the Salmon Anglers’ Association accused the Ministry of Works and Development of failing to repair the damage it had done to salmon rivers. He protested that until steps were taken to rectify the situation, a moratorium should be imposed on further applications for water rights oh river dam sites. “Every blunder of the past could have been avoided by compensatory schemes, fish passes, fish screens, or water storage,” he said. In a chronicle of destruction of the South Island salmon fishery, Mr Hughey listed: Premature commercial exploitation of the Waimakariri River between 1925 and 1956. An impassable dam built at Kurow in 1935 denying access for upward migrating salmon to the Waitaki and tributaries. Reduction of the Rangitata flow by a diversion race in 1945. Plundering of the normal summer flows of the Opihi for irrigation. Interference with the Ashburton for irrigation. Diversion of the Harper River into Lake Colleridge denying that river’s spawning area to the Rakaia and, The building of the Roxburgh dam on the Clutha. The Clutha, he said had a potential that was not realised until thousands of fish turned up at the dam. It was too late because there was no fish ladder for them to get through. Mr S. C. Sparrow, the Salmon Anglers’ Associ-. ation’s publicity officer, says that fish losses in the Waitaki River caused by the Kurctw dam and in the Clutha River from the Roxburgh dam to the

salmon fishery probably amounted to more fish than the total remaining today. In the early thirties a fish pass (salmon ladder) was built into the Waitaki River dam at Kurow, but because of its design it a.J not work properly. Instead of being modified to make it work it was declared redundant and flow going down it was diverted to provide water for i additional generator. In 1956 when the Roxburgh Dam was completed in the Clutha River a fish pass was not provided. Two very large salmon runs were stopped in their tracks. A fish pass has been built into the Mararoa Dam on the Waiau River in Southland, but paradoxically, there are no sea-run salmon in the area. The South Island has four major salmon rivers — the Rakaia, the Rangitata, the Waimakariri and the Waitaki — and the lesser Waiau, Hurunui, Ashley, Ashburton, Opihi and Clutha Rivers. The adults enter the river mouths from November, the main body of fish coming in during February and March. The bulk of the useful spawning occurs in the headwater spring-fed creeks from late April to June. Hatching begins in August and many of the tiny fish unable to establish feeding stations, usually because of overcrowding, leave their feeding stations immediately. The juveniles begin to leave the spawning streams from the age of three months onwards, about October. It is vital that irrigation intakes and power station intakes be screened to prevent the entry of these small fish, about 7cm to 13cm in length, said Mr Sparrow. The section on environmental considerations in the Steering Committee report asserts that if water is lost to the river, fish production will suffer proportionately. In relation to the Rakaia River sea-run salmon fishery, water abstraction results in a loss of freshwater salmon habitat for juvenile salmon and a loss of recreational opportunities. In 1976 when the Wilberforce River was diverted into Lake Coleridge one of the main reasons why there was little opposition to the scheme was that the Electrical Division of the Ministry of

Energy and the Ministry of Works and Development agreed to a suggestion that a spawning race be constructed at the Lake Coleridge outlet. That compensation measure was turned over to the Fisheries Management Division to organise but a self-sustaining spawning race was not built, only a row of several small ponds, each 0.1 hectares in size. Mr Sparrow said that nobody can suggest how these could contribute to significantly increasing the salmon run in the Rakaia without a major commitment of manpower and resources from elsewhere. “The original idea of an artificial spawning channel should work unaided and with only minimal manpower commitments,” he says. In contrast, runholders affected by the Wilberforce diversion are believed to have been compensated with five miles of fencing, three or four weeks of bulldozing, and two bridges each worth about $70,000. “Fish pass regulations in New Zealand are sorely in need of updating and are a constant source of frustration amongst anglers,” says Mr Sparrow. “It clearly needs to be mandatory that irrigation intakes and the likes have fish screens, passages for fish around dams, and where this is impractical there should compensation in lieu” he says. He cites the Hurunui

hydro scheme as such a case. On the basis of angling pressure and limited information on the trout and salmon fishery, Mr Sparrow says that the North Canterbury Power Board would hope to escape with slight fisheries compensation measures. That would not take into account the future demand for recreational angling opportunities from a growing population he says. The Huranui River is a freshwater salmon habitat and the area to be drowned behind the dam provides for some of the best river angling for trout in New Zealand. Mr Sparrow says that if the future demand for energy is such that storage in the Rakaia catchment is required and the full scheme of the Southern Energy Group is put into effect, then there will be two major effects on the fishery. First the increase in the size of Lake Coleridge and its subsequent fluctuations of about 30m in levels over 12 months, would spell the end for the recreational fishery as it is known. Possible compensation for this loss could be found by creating other lakes and enlarging existing lakes for the specific purposes of providing angling opportunities to match those lost by the conversion of Coleridge into an enlarged storage lake.

Second after the diversion of '8 per cent of the Rakaia catchment year round into Lake Coleridge, the flow in the Rakaia Gorge area would carry more sediment than the usual clear flows oi the Wilberforce and the outlet of Coleridge. “This must have an effect on the quality of the habitat for juvenile salmon in the gorge area and some method of putting some of this clearer water back into the gorge higher up would be desirable,” says Mr Sparrow. The present plan calls for the Coleridge outflow not to be spilled into the main river until the gorge bridge is reached. Mr Sparrow says anglers are deeply appreciative of the chance to be brought in by the hydro and irrigation people to help in planning the developmer of the river. In a recent letter to Mr Sparrow, Anthony Netboy, a noted American ecologica’ author, wrote: “I believe you have made a real coup in getting one per cent of the cost of the project to the fisheries. In the Pacific North West it has taken 40 years to put this idea across and now the Bonneville Power Authority which markets the power from all the dams in Oregon, Washington, Idaho and Montana kicks in several hundred thousand dollars every year for the fisheries.” — Denise McNabb.