Distance: 5.9 km (3.0 DOC hours) - Marked route - Easy-moderate terrain
Altitude: 1182m to 1866m. Gain: 391m. Loss: 1075m . Gradient: 15 deg (Moderate-hard)
Skills: Occasional scrambles (3/7) - Streams (2/6)

Marked route (6/9)
Uncut route, with markers normally within sight

Primary, mapped (1/5)
Formal route, on maps, principal access to hut or along range / catchment

Moderate-hard (difficulty: 4/5)
Continuous moderate climbs

Easy-moderate (difficulty: 2/5)
Tussock / river-gravel / open bush / cut track

Occasional scrambles (difficulty: 3/7)
Tramp with some scrambles and exposure to falls

Streams (difficulty: 2/6)
Small streams, danger only in extreme weather

Unknown (difficulty: 0/7)
Not specified

Descending Waiau Pass on the North side into the Lake Constance basin is a straightforward descent in scree, following a poled route. The route crosses the stream at the head of the valley, followed Lake Constance on the left (West) (Figure 21a), climbs above bluffs at the lake head, over a large boulder field, after which views of the beautiful Blue Lake / Rotomariewhenua are gained (Figure 21b).

Note: Described in the reverse direction to your journey

From Blue Lake, the route is poled all the way to Waiau Pass (and on to the valley floor).
Initially gently rising and open, once to the trees the track steepens. A rising track leads to the true left of Lake Constance brings you to a steep scree climb then a traverse to the mid-point of the lake.
Although there have been recorded deaths above the lake, the track is straight forward. However, take care if you choose to approach the top of the bluffs as the fall to the lake is sheer.
The poled route leads to a steep descent in a gut and to the lake shore – then along to the lake head and across the valley floor (good campsites 100m before the start of the climb) and up up up to Waiau Pass.
It’s steep but the initial section on larger rocks is stable. The track moves onto a grass tongue until an obvious footpad angles up, across the scree, towards a grassy shelf. A useful tarn at the base of the final ascent to the pass means less water needs to be hauled up from the valley.