Lake Opuha, South Canterbury, New Zealand

Lake Opuha - South Canterbury

Lake Opuha  - taken by me August 1999. 

Lake Opuha, a recreation reserve, just out of Fairlie at the head of the Opuha Gorge. Mount Walker, named after the first owner, the Walker brothers, of Four Peaks Station, height: 5425 ft. is the snow capped flat top hill reflecting in the 700 hectare man-made lake.  Stored winter and spring river flow will be released in summer for stock watering and domestic and industrial use in Timaru and irrigation between Washdyke, Temuka, Cave, Pleasant Point, Totara Valley and Fairlie. The dam will provide about three thousand homes with power (7.5 megawatts). 

Construction on the $32 million Opuha earth dam commenced in 1995 and completed in 1998 after a disaster in February 1997 when water surged down the Opuha River, wiped out the approach to the Skipton Bridge, and tore chunks out of land before roaring into the Opihi River system.  It ruined vast tracts of farm land, killed stock, and turned fertile paddocks into instant riverbed and flooded the house at "Blueview" Raincliff Road.  Damage to the dam was cost at $8m. A further $4m of damage was caused to farmland downstream. The 700ha Lake Opuha flooded the land east of the Clayton Road on Sherwood Downs, Opuha Gorge Road and "Corra Lynn".  Land was purchased from seven farmers for the project.  The Opuha dam and lake was officially opened 7 November, 1998, by the Mackenzie District Mayor Neil Carmichael Anderson and the power plant has been operating for some time.  Opuha Water Ltd (OWL)

In 2018 Lake Opuha's dam will undergo upgrade work to construct a one metre high concrete lip extending 300 metres across the top of the dam. The lip would form a wave barrier in an effort to offer "maximum flood protection".

The 50 metre high earth dam features a single hydro turbine, fed by Lake Opuha which covers about 710 hectares and stores more than 74 million cubic metres of water. Water storage is prioritised for release into the Opuha River which flows into Opihi River to ensure minimum flows are maintained at all times and especially in times of drought and/or low natural flows.

[Corra Lynn was the kind of place, like the Pareora Dam, and Andrew's Stream gorge, Orari Gorge Station, where a childhood visit becomes a life-long memory.  For local children of Sherwood Downs and Ashwick Flat and parents that was the place to go for a picnic with visiting cousins. Vehicles by the dozen were parked under the large pine trees facing the crystal clear moving North Opuha River.  Mothers would take the younger kids to the pool on Gooseberry Creek and sit on blankets watch and chat while the youngster would stand on the rock in the middle of the mini waterfall and jump in and gain experience.  The braver kids would climb around and jump off the 8ft cliff.  The teenagers would head in the opposite direction and swim in the Opuha River, jump into the deep swim hole from the rocks.  At night we would go down to the same swimming hole in the river, not the creek, with a dead hare, shot that day, binder twine tied to a couple of its legs, a spotlight and gaff and get half a dozen eels and take them the next day to my Grandmother's and Aunt's house in Timaru. They liked eel. Those two swimming holes are under water now. ] "For many their emotional attachment to a river is rooted in their childhoods. Looking at the rugged back country, the bush, the cliffs, pools and mini waterfalls I start to see why this little river generated such strong feelings." Eel is awfully oily to eat. Always soak it for a couple of days in water to get rid of the mud.

Testing to pick top spots BY DAVID BRUCE
Otago Daily Times 13 December 2007
Safe swimming. UNIVERSITY of Otago student Sara Fraser has a dream job this summer visiting about 50 of South Canterbury's favourite swimming spots every week. The chemistry student is working for Environment Canterbury collecting water samples to be tested to ensure the water is safe for swimming. She covers an area from the Ashburton lakes to the Mackenzie lakes, and south to the Waitaki River and its lakes. "The best part is driving around and seeing these amazing spots. It's a fun job and it's good for my studies, especially because I got to see the lab and may be able to apply the work to what I learn next year and in the future," she said.
Three weeks into the job, the Orari Gorge rated as her favourite site, and she reported the water quality there was good.
A small number of swimming spots in South Canterbury are of poor water quality - the Waihao River at the Black Hole and Bradshaws pools, Lake Benmore at Pumpkin Bay, Lake Aviemore at Loch Laird and Lake Opuha at Ewart's Corner boat ramp.

The best water quality in the South are the dam boat ramp of South Canterbury's newest lake, Opuha, near Fairlie, Lake Benmore at Ohau C and the Lake Ruataniwha camping grounds beach. At each site, a sample is taken where the water is 1m deep from a depth of 0.5m. The samples are then sent to Environment Canterbury's (ECan) laboratory in Christchurch for testing. The results are sent back to Miss Fraser who gave the information to the relevant district councils and checked the ECan website, , was updated. She said other areas with good water quality so far were Lake Middleton, near Lake Ohau, and Lakes Benmore, Ruataniwha and Aviemore. The region's most popular swimming spot, Caroline Bay in Timaru, was also returning good results. Miss Fraser said factors such as rainfall could affect quality as there was more run-off into the rivers and lakes.

The Opuha Dam's lower shingle weir, designed to wash out in a one-in-five-year flood, washed out 13 Jan. 2001 when inflows in Lake Opuha peaked at 130cumecs with electricity generation needs only taking 15cumecs. The lake level peaked at 1.63m above the spillway, the highest the lake has reached since its creation. Lake Opuha boasts three introduced species of fish.  Rainbow trout were in the river before the dam was built; brown trout and salmon have been released since. Lake Opuha salmon are landlocked by the Opuha dam and generally have a life expectancy of three years. The Central South Island Fish and Game Council released 35,000 juvenile salmon in January 2003.  The bag-limit is six because of their high survival rates.

To get there from Fairlie, take S.H. 79 head towards Geraldine, cross over the Opihi River bridge near the Fairlie camping grounds, take the first left, Clayton Rd, a long straight tar-sealed road with a view of Mt Dobson, and drive through Ashwick Flat looking towards the Two Thumb Range and Fox's Peak. The lake will be on the right, can't miss it. About 12km N.W. from Fairlie.

Lake Opuha, and the Two Thumb Range  1998. Taken from the Trentham Rd at Bennett's gate.
Lake Opuha contains three introduced species of fish, rainbow trout, brown trout and salmon.

The Christchurch Press 16 Nov. 1999
FAIRLIE - The Mackenzie District Council has granted consent to Opuha Dam Ltd to develop picnic areas and buffer zones around Lake Opuha. The development around the new 700ha lake will also include car-parks, access tracks, lakeside plantings, landscaping, and walking tracks. Areas to be developed include Sugarloaf Creek, Clayton Road, Corra Lynn, and Trentham Road picnic areas, and a condition of the consent is that they be developed within 12 months. Another condition is that plantings be with species that reduce or avoid contaminating the lake, and that, where possible, local species be used.

April 2009 Rain hit the region again, with the deluge blowing out the fusible plug in the Opuha Dam weir, closing bridges and roads and stopping trains.

Timaru Herald     5 July 2006   Opuha Dam shows worth of irrigation
The 16,000-hectare Opuha dam irrigation scheme proves the worth of investing in irrigation. A draft report covering the impact on the local economy and community from the dam shows there is $7.7 million per year in extra productivity on farms and that it has provided 30 full time-equivalent positions for every 1000 hectares. The Opihi was a significant salmon and trout fishery and in the 2004/05 season more salmon were reported caught in the Opihi than all the other major salmon fisheries. Fish and Game stated that the mouth had been kept open for many more days per year than previously. It was now four to five days of closure per year compared to 100 plus prior to the dam.

Timaru Herald 5 November 2007 BOOK
"They went out and built the dam and then they went and built it again when it fell over," said farmer and chief executive of the Opuha Water Partnership Peter Scott, referring to the February 1997 collapse. The book, A Dream Fulfilled � The Story of the Opuha Dam  by Jill Worrall published by Opuha Water Ltd. $69.95, is for sale at Chapters and Verses in Stafford Street, Timaru. The book details the dams development from the 1980's drought-inspired inception to economic and environmental stability was launched 5 November 2007, 25 years after the first meeting to discuss the idea to try to enhance the Opihi and Opuha river systems. 

John Keast 1 December 2007 The Press (Christchurch)
The story of the Opuha Dam is a story of South Canterbury, and now it is told in a new book. Drought is the curse of the land and it came to South Canterbury in the 1980s and did not leave. It sucked the life out of the land and eroded the spirit of those farming it, and, in a strange way, it created a revolution. South Canterbury, then, had little in the way of irrigation -- and there are constant cries still for more water -- but the terror of the nor'west winds of 1982, 1985 and 1988 focused as never before the minds of those whose job it was to tend stock and raise crops. Tom Henderson was one of those men. He is retired now, and living in Pleasant Point, but he could see then the need for water storage. It was, he says, the only way to get around drought. He believed then, as now, that if the region was to have a prosperous future, it had to come from the land. Henderson was instrumental in forming the Opihi River Augmentation Society, a wordy title for a group that became the driving force that led to the creation of the Opuha Dam near Fairlie. Much has been written about that dam; about its creation -- its devastating collapse -- and its rebuilding.

And now Timaru author Jill Worrall has written a book on the dam -- A Dream Fulfilled, The Story Of The Opuha Dam -- for Opuha Water Ltd. Worrall's book is more than a set of facts and photos; it is about the tenacity of South Cantabrians; about guts and drive and an unswerving will to succeed. It is also, in no short measure, about politics, pressure, disappointment, elation and drought. The scheme has been going for a decade, and those who had any part in its creation gathered in Timaru recently to celebrate what has been a long and hard road. Now, the dam, and its associated irrigation scheme, are held up -- and rightly so -- as what can be achieved when water can be stored. In South Canterbury's case, it is much. The dam, giving surety of water supply to farms, has led to the creation of 500 new jobs; augmented the Opihi River to the point where once again it is an anglers' delight; created a very popular recreational lake near Fairlie, and, not least, generates electricity. And it was all done by private enterprise at a time when the Government was the only body building dams or creating anything like a major project.

Back to Henderson. If he is delighted with the project -- and he is -- he has every right. He reckons having local people on the project was a major reason for its success. Now, the scheme is owned by its farmer shareholders, giving Henderson real confidence in its future for the benefit of the whole community. But to know its success is also to know of the dam's big failure. Few will have forgotten the news of February 6, 1997. It was calm in Timaru, but near Fairlie, a lake began to form behind the dam, fed by three days of steady rain. It rose and rose and, eventually, led to the breaching of the dam, sending a thundering wall of water towards the Skipton Bridge, punching it out, and then into the Opuha and Opihi river systems. More than 200 people were evacuated and, almost unbelievably, no one was killed as the water surged to the sea. More than 1000 animals, though, lost their lives. The breach caused $8m worth of damage to the dam, and downstream farms suffered losses of around $4m. South Canterbury, for all the wrong reasons, was in the national news. The devastation was huge; the dam gutted and rent apart. It was fixed, at no small cost, to be the success it is today, a decade on. But that breach led to prosecutions by the regional council, ECan, something that still rankles in South Canterbury -- and something not forgotten today as various councils in Mid and South Canterbury talk loudly about the likelihood of backing the formation of a central South Island regional council.

Former Timaru Mayor Wynne Raymond says now of the prosecution of Chris Hollingum, the foreman of dam contractor Doug Hood Ltd: "Chris Hollingum deserved a medal, not a criminal charge. What the regional council did to him is still a source of utter fury -- even today." After its breach it took nine months to put the dam back to the state it was before its collapse. On a sunny day on November 7, 1998, the dam was opened. It was a red-letter day for South Canterbury. The late Sir Peter Elworthy arrived in his yellow Tiger Moth and, thudding in from the coast, came a World War 2 fighter. It was stirring stuff; a dream turned reality. Worrall's book has captured it all. The dam story is one of grit and courage, of the triumph of individuals. It is, frankly, a good dam read.

Looking towards Fox peak, the High clayton's and Butler's Saddle on the Sherwood Downs Range.

Opened 7 November 1998 by Neil Carmichael Anderson Mayor of Mackenzie District.
A community dream turned into reality.

Timaru Herald, 30 June 1886, Page 3 The Bridge Bubble
To the Editor of the Timaru Herald
Sir, As the Raincliff and Sherwood Downs estates are the only parties likely to derive any benefit from the building of those bridges (Opihi and Opuha), and the Mount Peel Road Board have more money than they know what to do with, let the two estates pay one half cost and the Mount Peel Road Board the other. I have no doubt the present bridge at Clayton is a noble structure of engineering skill if the Opuha could only be induced to flow under it; but, sad to say, the stream and the bridge have entirely dissolved partnership. The bridge will last for generations to come simply because it will never be used, except by some inquisitive passer-by, who may venture a trip across simply to try and find out what it was put there for. It is a well known fact that as soon as the natural course of streams (I cannot say rivers in this case) are interfered with on these plains, they shift their course immediately. I have only to allude to the several bridges on the Rangitata and Waitaki also the Fairlie creek bridges. The stream having threatened the township ever since the structure was erected. I am, &c Another ratepayer.

South Canterbury NZGenWeb Project

The Opuha Dam, Nov. 2009.
On 17 May 2009 rain hit the region again, with the deluge blowing out the fusible plug in the Opuha Dam weir, closing bridges and roads and stopping trains. 
The dam reached a level of 393.2 metres. It is considered full at 390m.

The Tengawai River flows east for 35 kilometres before joining the Opihi River north of Pleasant Point. From the Rollesby Range catchment area the Opawa, Line and Rocky Gully Rivers drain into the Tenagawi around Albury. Other tributaries of Opihi are the Temuka River to the north (with its major tributaries the Te Moana, Kakahu and the Waihi streams) and the Opuha River. The headwaters of the south Opuha covers the catchments for the Two Thumbs Range and the river is now dammed at Corra Lynn. Map

2008  2006 feature dairy

Life in the Young Colony Reminiscences of W R Keay, the former owner of Corra Lynn Station, Sherwood Downs

Ashburton Guardian, 22 March 1909, Page 2
The Mount Peel Road Board met on March 19th, when there was only a bare quorum present. The overseer reported that all work had been at a standstill, as the men had been away harvesting. Plans and specifications for the-light-traffic bridge for Sherwood Downs Creek, on the Clayton road were completed. A length of say 85 chains of the Mid-Valley road required a coat of metal, but there was no quarry available unless the adjoining owner would allow spalls to-be quarried his land. The Fairlie gang would be put on to cart out metal on the Mount Michael road. The Board decided that the metalling on Mid-Valley road should stand over. Accounts amounting to �57 4s 61 were passed for payment.

South Canterbury NZGenWeb Project