The Blue Grey starts its life at Lake Christabel in the hills behind Springs Junction at the northern end of the Lewis Pass. The river flows very swiftly from the lake down to where it joins the Brown Grey. The smaller Brown Grey may hold fish during spawning season but generally is rather too small to afford the cover needed by decent size trout. The Blue Grey River is much larger, being sourced from Lake Christabel, so there is plenty of holding water for trout all the way from the lake down.

Trout were released in the lake years ago but locals insist that there are no longer fish in there. Fishing spots are hard to find in the headwaters as a large volume of lake-fed water pours down a narrow gully. It is a matter of hiking up the track to the lake and peering through the trees to see if you can spy some small pockets where the river momentarily slows its headlong charge down the valley. There are only a few such pools to be found in the hour or so walk to the lake and they are easy to miss. When you find one, it will be short and fast so it is necessary to fish the quieter water at the edges. If you manage to hook a fish, your problems will have only just started, as they will be off downstream as soon as the hook is set.

The better fishing water is found down from the bridge at the farm on Palmer Road opposite the start of the track up to the lake. The river meanders its way through farmland for a kilometre or so down to its junction with the Brown Grey. From here to the Robinson confluence the river is known as the Upper Grey River. On the corner just below the junction is a deep pool that always harbours some big trout. However it is fished regularly by the locals so any trout in the pool are very wary; even by South Island brown trout standards! 

Further down the river enters the bush section. As long as the water level is normal, you can edge your way up either bank with only the occasional bit of bushbashing needed. There are some classic pools and a lot of riffly water and most of the fish will be found along the edges of the secondary channels.

Palmer Road continues to follow the river for several kilometres, finishing at a farm gate marked ‘Private Property’. It is necessary to call in at the farmhouse to gain permission to travel through the farm. From the end of the farm road, it is a short walk to the confluence of the Blue Grey and the Robinson Rivers, where the Grey River proper can be said to start. From here, it is 13 km through some rugged country down to the next access. This is one of the most beautiful rivers in New Zealand, crystal clear water flowing over clean river stones and big boulders.

The stretch above the Robinson confluence offers delightful fishing in a beech-flanked gorge. It is quite possible to work right through the gorge up to the start of the farm. Although the water flow is strong, there are plenty of obstructions to give shelter to the hardy browns.

There are riffles, runs, deep pools and many secondary flows where the fish tend to hold. From the junction up is as good as South Island fishing gets – good fish in crystal clear water, with beech forest for a backdrop.

However the Upper Grey is coming under increasing angling pressure, especially from the professional guides who obviously find it a good river to give their clients the real Kiwi outdoor experience without the cost of a helicopter or the inconvenience of tramping in. This makes it very favoured by professional guides. One suspects it cannot be far off when the local farmer closes off access in a deal with a guide, as is happening in many North Island rivers.

Compared to a few years ago, there are a lot more anglers and the days of having the river to yourself are long gone. This means spooky fish needing careful approaches and delicate presentations, especially if they are lying shallow. It is also not the river it used to be, having been severely affected by the huge flood in February 1997. This changed the river drastically and ruined some lovely pools and riffles. One riffle in particular always will stay in my memory – a 500 m long run that you could wade up quite easily casting to rises left and right.

One hot February afternoon saw me spot over 20 fish up this riffly run, about half of them on the rise. They were taking freely and it took me 3 hours to do the 500 m with 10 fish being hooked. You tend to treasure magic days like that – they are becoming scarcer.

I usually start fishing around the area called Cattle Flat as this area is popular with the local guides. That is usually a good sign, as those guys have to produce fish for the paying customers. There is a copse of big beech trees that leads to a pool that is the first big pool before the gorge that goes all the way down to the Robinson River junction.

If you creep up to the edge of the trees and stare intently into the greeny-blue pool, you will usually see a gray smudge. That is what the Upper Grey trout look like in the river. Usually there is a trout to be seen above the big boulder in the middle of the pool. It always pays to look for feeding trout above rocks as well as behind them. There are a significant proportion of trout that lie in front of rocks – nearly as many as those that are to be found sheltering from the flow in the more obvious spot behind rocks. Usually the trout in such positions will take freely to a well-presented size 12 Beadhead Hare’n’Copper.

The more difficult Upper Grey trout are to be found deep in the large pools. They can be easily seen but getting down to them in the turbulent current can be difficult. It is then necessary to adjust one’s terminal tackle.

My fishing success had improved a lot when I learned to adapt my rig to the depth and speed of the water. As this changes, so you have to change your tackle. This may involve changing the leader length to suit the depth of the water and changing your fly weight to suit the speed of the current. The quickest way of changing your leader length is just to move your indicator. The shallower the fish is lying; the nearer your indicator should be to your fly.

Similarly, the easiest way of adapting to the speed of the current is to change the weight of your fly. For years, I have preferred to do this through the use of a sinker fly with a small, more-likely-to-be-taken fly attached to the bend of the larger hook.

If the fish is lying deep, then he is unlikely to be put off by the larger fly and it is surprising just how often a fish will take the larger fly by preference. Generally rainbows tend to be more prone to do this, but often a big brown will be tempted by a large stonefly, sometimes when all else has failed. As soon as you come to shallower stretches, it is a simple matter to remove the double rig and tie on a single small fly.

On a river with a wide variety of water, such as the Upper Grey, you will need to make changes quite often. If you have been fishing a fast but shallow riffle and the pool at the top is a large deep one, then there is no success to be had from leaving on your effectively short leader and lightly-weighted flies. Unless the fish are holding high in the pool, they will be unlikely to come up for your fly. It is necessary to lengthen the leader and change to a weighted fly. Your success rate is bound to improve if you keep putting the fly at the exact depth at which the fish are lying. This is not ‘rocket science’; just plain common sense.

Whatever your success on the Upper Grey, the serenity and beauty of the beech forest around you add considerably to the pleasure of fishing this glorious wild river.