OPINION: The lower Waiau River was once New Zealand's second largest, after the Clutha, but now with most of its water being discharged through the West Arm power station it is just an ordinary river.
There are many stories about the Waiau of old, from the fly fishing at the outlet where Pearl Harbour now is near the Manapouri township, to the sea trout and salmon at the mouth.
These are distant memories. Now, instead of the average flow of about 450 cumecs from Lake Manapouri, the summer flow is 17 cumecs unless there is a flood. This sounds like not much more than a trickle but it is actually a big body of water, by the time its many tributaries make a contribution it is double that and more when it flows into the sea. It's about the same size as the Mataura, our next biggest river.
Compared to the Upper Waiau it's a small river though, and its trout population is smaller too. Less than half on a per km basis even when the lower Waiau has a good year, about 70-100 large trout per kilometre compared to 300-400 per km in the larger river.
Fisheries biologists can calculate the amount of water needed to sustain a trout fishery but this is an inexact science. The 17 cumecs was calculated to provide a good trout population and 70-100 for each kilometre is pretty good, but there is no doubt that more water equals more fish. Water has other uses so it can't all be used to provide homes for trout.
The lower Waiau is still a nice river to fish, with lovely runs and deep clear green pools, especially in the reaches upstream of the Wairaki.
The Waiau Trust has created several good access points to the river. Most of the trout are 20-30cm rainbows that take a lure or dry fly readily at times. These times can be a bit sporadic and short-lived. But if you do have a bright fly drifting along in a sparkling riffle when they are in the mood you can be sure of some lively action. A sunny morning with the Fiordland Mountains as backdrop makes this a beautiful place to cast a fly or toss a lure.
For updated river conditions visit www.es.govt.nz/rivers-and-rainfall, and for fishing licences and information go to fishandgame.org.nz. For videos of trout fishing in Southland Google Maurice Rodway You Tube.
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