Fishing Report
Mixed reports this weekend. Saturday was fine, then Sunday was wet with light misty drizzle all day (great for Pip’s pot plants!). Some guest anglers reported fish everywhere but none caught. Others moved around more and landed and released a few and kept the odd fresh run rainbow for smoking. TRM’s most successful team (see photo right) were David Butterfield and Tony Hill from Wellington introducing Andrew Butterfield from Ch’ch (Yes, he cleaned his fishing gear three times) to the delights of the Tongariro town pools. Their best result was once they left the town pools with the dry fly in the Birches on Saturday night. On the wet Sunday morning they did the Braids circuit around the Honeypot from where they kept the fresh pink rainbow in the photo. Pip reports they also took home a big brown but were very vague about exactly where this was caught…
Update on Tongariro Flows in January
(Photos below are from Beggs Pool in the upper river where water for Lake Rotoaira is extracted and channelled through tunnels to emerge in the Poutu Canal on left)
TRM are still receiving questions from readers seeking an explanation for what happened in January when the Tongariro River experienced continuous daily fluctuations. Many were very alarmed as such erratic flow movement could have had serious consequences on aquatic life in the river if it continued. Fortunately the river was returned to steady low levels in February.
Also fortunately seeking answers was the "Advocates for the Tongariro River" Secretary, Eric Wilson, who kindly sent TRM their minutes from his meetings. TRM thank him for his assistance which should provide some of the answers.
Again this demonstrates why TRM have been asking, indeed, sometimes even begging many regular Tongariro River anglers to join the Advocates. When there is any crisis on the river it appears they are your only reliable "representatives" who are prepared to ask the hard questions and act on behalf of all anglers in the wider interests of protecting the future of the Tongariro River and the Fishery.
The following confirms that if it wasn’t for the Advocates then we would all still be guessing. This may appear to be a bit boring and pedantic for a few readers who may only want to know where to catch trout, but any such significant interruption of the flow, as indicated in the graph, could have significantly damaged the fishery. As such it deserves a full enquiry and anglers deserve a full explanation.
Anglers requiring more information on how to join the Advocates should go to Links.
Minutes from:
Eric Wilson (Secretary/Treasurer of Advocates For The Tongariro River)
Meeting with
Doug Tucker (Operations Manager Renewable Energy, Genesis Energy).
At Tokaanu Power Station
11.00 am 7.2.08 (Last Thursday)
The Genesis Hydrology Chart (refer "Advocates" web site – go to Links) showed this unusual pattern during the period when river users were advised that the river was returned to full flow.
It is evident that rather than full flow, the flow was being manipulated through a process called ramping. Ramping is the raising or decreasing of the river flow.
I sought initially an explanation for this regime from Jarrod Bowler of Genesis Energy and this morning visited the Power Station and discussed the matter with Doug Tucker, Operations Manager, Renewable Energy. Their explanation:
1. The country is experiencing a very dry period and with a high demand for electricity coupled with a short supply, particularly in the North Island, has led to high electricity prices and the need for the best utilisation of water storage.
2. Genesis is required to run the Rangipo Station to produce electricity. They agreed to run only one turbine and notified us of that.
3. The only major water storage for the scheme is Lake Moawhango which at the start of the Poutu Canal outage was 24%. Today (08/02/08) the level is 9%.
4. The optimum level of production from 1 turbine at Rangipo is 60MW and to achieve that extra water is fed through the tunnel from Lake Moawhango to Rangipo Dam.
5. There is insufficient water in Lake Moawhango for continuous running at 60 MW for any continuous substantial length of time, therefore the company reduces generation to 30 MW overnight which is approximately the natural flow of the Tongariro River. This reduces the rate of lake level recession at Lake Moawhango. Lake Moawhango. When national demand for electricity lessens then Lake Moawhango storage can be increased, reducing generation at Rangipo.
6. The fluctuations of 130mm in the Tongariro River are therefore caused by national demand for generation which has resulted in the release of water from Lake Moawhango altering the flow through Turangi as described by the graph.
7. Doug was unaware of any concerns being raised by river users as a result of ramping. This ramping of flow both up and down was at a controlled rate of 2.5 cumecs per half hour. The change from 30 MW to 60 MW is an increase of 130mm stage height of the Tongariro River at Turangi with a change rate of 45mm per hour, or three hours total time for the change.
8. Doug was advised late yesterday of a query regarding concerns to the fishery as a consequence of this process but had not been given the details yet I would discuss the matter with DoC fishery which I have done.
Meeting with Glen McLean
DoC (Department of Conservation) Office
Tongariro/Taupo Conservancy
Taupo Fishery Managers
11.45am 7.2.08 (Last Thursday)
1. Glen was aware of the issue through many concerns sent to DoC and had phoned Jarrod Bowler
2. Jarrod Bowler of Genesis Energy had been away and was not aware until yesterday of the operation.
3. Glen said that the procedure was not good for the fishery but acknowledged the difficult position Genesis is in.
4. Said that he would organise a meeting to explain what had happened.
Eric Wilson
Secretary/Treasurer
Advocates For The Tongariro River