When it's released from the heavens, water that is destined to become the Waiau River lands on high mountains, then tumbles over granite cliffs, winds its way through limestone caverns and around gnarled beech tree roots to enter the still, deep waters of Lakes Te Anau and Manapouri, where it sits.
That which eventually finds its way to Pearl Harbour, just a small fraction of the total, crashes through the gates of the Mararoa Weir, then leisurely flows to the sea.
In the past three months a lot of this water has been flowing to the sea at Papatotara, but now with the wet westerly rains holding back, the lower Waiau has shrunk to its normal post-dam development flow.
It's not nearly as impressive as it once was, but it's still a nice river which is worth a visit for the purpose of trout fishing.
Didymo causes problems in the lower Waiau, but after the high flows it exists only as small blobs on the big rocks and much of the bed is clear and clean.
The river is hard to fish with a fly, but the riffles and shallow runs have plenty of small rainbows that readily take any kind of fly.
The deeper pools and runs are more suited to spin fishing and soft baits. Many of these are quite deep so you need to sink your lures down towards the bottom.
A slow retrieve, from an upstream cast, is more likely to produce a fish. There are lots of grassy edges where the water flows sedately along.
Where this is about a metre deep, big brown trout lie in wait. A lure teased along, right beside the grasses, or a dry fly drifted within a trout's eyesight of the bank will also lure a big fish into your grasp.
As the summer progresses, didymo will grow and become a nuisance, so get out and try the Waiau soon, while it is still pretty and pure; not as grand as it once was, but still a nice trout stream.
Tip: Try a Royal Wulff dry fly or a silver and blue soft bait on the lower Waiau this weekend. For updated river conditions visit www.es.govt.nz/rivers-and-rainfall. Fishing licences and information - fishandgame.org.nz
- The Southland Times