Waiau Pass Route

Waiau Pass Route is a one-way, 16.7 km alpine crossing from Blue Lake Hut to Waiau Hut over the 1,870 m Waiau Pass. Allow 10 to 13 hours. This is an expert tramp, not a day walk: the route is remote and calls for strong fitness, route-finding, river-crossing and snowcraft skills. Blue Lake Hut is reached on foot as part of the Travers-Sabine route, and both huts require bookings.

Leave Blue Lake Hut on the orange markers and poles. The route climbs the moraine holding Rotopōhueroa/Lake Constance, then stays high above the lake's western cliffs, crossing steep gullies and spurs before dropping to the shore near the lakehead, about 2.7 km from the hut. Don't follow the shoreline as a shortcut; bluffs and deep water bring it to a dead end. From the lakehead, follow the open valley floor for about a kilometre, crossing several streams, then climb scree and steep rock for about 1.5 km to the saddle. That final climb gains 530 m, and hard icy snow can linger on its upper slopes into December.

At 1,870 m, the pass is the crux. The south-side descent is very steep and technical, with loose rock and a real slip risk. From the saddle, follow the marked route to the right; going straight down into the valley is the wrong line. The route then reaches the west branch of the Waiau Uwha River, drops through thick subalpine scrub and crosses to the east branch near Upper Waiau Forks. A beech stand and informal camping clearing sit at the forks, but there is no hut there.

Below the forks, the marked route follows the river downstream, first on its true left, then crossing to the true right. Tread can be overgrown, so keep track of the orange markers. Expect more side-stream crossings, including Caroline Creek; allow about four hours from the forks to Waiau Hut. Caroline Creek Bivvy has been removed, so don't count on shelter there. Waiau Hut is the next roof, with six bunks, a non-flush toilet and untreated tap water that must be boiled.

Time estimates vary: one description gives 9 to 12 hours for the crossing, while its split section times add to 10 to 13. Plan for a full day and room for delays. Snow can be present on the south side at any time of year, and dangerous avalanches occur regularly. The recommended season is December to April, but summer does not guarantee safe conditions. If snow covers the south slope, turn back unless your party has the training and equipment to manage it, including an ice axe, crampons and avalanche rescue gear. Carry a distress beacon, emergency shelter and enough extra food for several days; weather or high rivers can keep parties at Blue Lake Hut longer than planned. There is no road access at the start, and dogs are not allowed.

Rotomairewhenua/Blue Lake and Rotopōhueroa/Lake Constance are tapu and culturally significant to Ngāti Apa ki te Rā Tō. Don't touch or swim in them, wash in them, take water, or put gear in the water. This also helps protect the lakes from lindavia, an invasive alga that causes lake snow. Hut taps provide untreated water, which must be boiled before drinking.