Distance: 2.7 km (2.5 DOC hours) - Unmarked route, hard - Moderate-hard terrain
Altitude: 546m to 1284m. Gain: 1027m. Loss: 303m . Gradient: 31 deg (Steep)
Skills: Prolonged scrambles (4/7) - Occasional rivers (3/6)

Unmarked route, hard (8/9)
Unmarked route, no clear geographic features to follow

minor (5/5)
A viable route, not widely used

Steep (difficulty: 5/5)
Steep climbs of >1000m

Moderate-hard (difficulty: 4/5)
Tall, walkable scrub / large rocks, occasional waterfalls or gorges in rivers

Prolonged scrambles (difficulty: 4/7)
Scramble, frequently on exposed ridges, spurs, faces

Occasional rivers (difficulty: 3/6)
Occasional rivers - impassible after heavy rain

Unknown (difficulty: 0/7)
Not specified

No description

Note: Described in the reverse direction to your journey

I do not recommend this route. I include it here for information only. Possible there are good routes N/W off pt1315, but in mist / clag I failed to find them. From the Otehake Hut book, the route up Chasm Creek and over the saddle north of pt1591 is a better route than the one documented here. Alternatively the descent to the Koropuku/Tawhana forks looked tough but also better - with possible routed down the river to the Otehake or up to Big Tops Hut. Finally, it may be possible to drop directly west off pt1315 down more southerly spurs to hit the Otehake upstream of its gorge. However, in poor visibility no route could be spotted.

My Route:
From pt1315 the narrow ridgeline runs north for a few hundred meters. Western faces are very steep, and in poor visibility no routes down to beech forest below were visible - but they may exist if you can see more than 10m!

I followed the ridgeline north, dropping down a series of 2 bluffs by seeking out good routes on the eastern side, returning to the spur after each. This got me to the scrubline. A third line of bluffs runs across the head of the slip shown dropping NNW on the map, and blocks progress directly north down the spur. I dropped NNW through steep but reasonable but very scrubby route down to the base of this bluff, then pushed north along its base to regain the spur dropping north to the Tawhana/Koropuku confluence where beech forest commences.

The route down to the Tawhana/Koropuku forks looks viable, but I wanted to go west to the Otehake. So I sidled west in thick scrub below the bluffs I'd just descended, but avoiding dropping too far into what are impassable steep rocky guts below where the map shows the slip. The route round the 5-or-so head basins of this slip was possible staying in thick scrub - but not recommended. Finally this sidling took me into mature beech forest beyond the slip on the spur dropping to the Otehake/Koropuku forks.

I dropped down this spur NW for 200m to where it forks with one spur runnigng NW to the forks and the other due west to the Otehake. I took the western spur, but soon regretted it - the NW one may be better.

The spur was choked with windfall, vines, scrub and made very slow, steep travel due west to the Otehake. The Otehake itself was in a 20m deep gorge where the spur meets it, and it took 20 minutes to find a viable, very steep scrub-climb down to the river, 100m-or-so north of the spur. I then returned upstream to the base of the spur and climbed a scrubby slip I had spotted on the western side of the gorge. OK, but very thick scrub.

Once over the lip of the gorge I was back in mature forest with deep windfall and vines. A further 120 vertical meters of climbing up the valleyside through this thick bush was required to reach the Otehake 'track'.

The Otehake Track is little more than a badly marked route, and had no visible ground trail through the windfall where I met it. I was lucky to hit it at a track marker or I would have missed the track entirely.