Lake Pukaki

LakesCanterbury (Mackenzie Basin),New Zealand

A sheet of opaque turquoise coloured by stone ground to dust beneath two glaciers, with New Zealand's highest mountain standing at the far end.

September·Edge of season

Sep–Oct

Early spring is the shoulder: snow retreats up the ranges but Aoraki keeps its fresh cap, mirrored on calm mornings; the days lengthen and the crowds stay away in the weeks before the lupins arrive.

Year-round The milk-turquoise water and Aoraki's snow-capped summit are here every month; the lupins, the colour's peak and the galactic core are not.

Lake Pukaki is a sheet of opaque turquoise with New Zealand's highest mountain standing at the far end of it. The colour is rock. The Tasman River arrives carrying glacial flour, stone ground to a talcum-fine dust beneath the Tasman and Hooker glaciers. The particles hang near the surface, scattering blue and green light back at you while the reds are absorbed. Framed head-on from the northern end is the source of that flour, Aoraki/Mount Cook, at 3,724 metres. It is shrinking: a rock avalanche tore off its summit in December 1991, and a 2013 resurvey found 40 metres of mountain gone. The lake itself now sits 46 metres higher than nature left it. Engineers dammed the outlet twice for the Waitaki power scheme, 9 metres in 1952 and another 37 in 1976, drowning a small island called Five Pound Note. Come to the State Highway 8 lookout on a still morning and Aoraki doubles itself in water that barely moves. From late November into December the road verges and the lake's eastern arm run purple and pink with Russell lupins. They are the most photographed foreground in the country and a quiet ecological disaster. Garden escapees, scattered along these roads from 1949 by a runholder's wife named Connie Scott, they smother the bare braided gravel that the kakī, or black stilt, needs for nesting. Roughly 141 adults survive in the wild, nearly all of them in this basin, propped up by a breeding centre at Twizel. Stay past sunset for what the daylight cannot give. In 2012 the Mackenzie became the first place anywhere certified a gold-tier dark sky reserve, and on moonless winter nights the core of the Milky Way stands over the turquoise.

Worth knowing

Good to know

Side-light beats midday — the turquoise reads deepest in the low sun of early morning and late afternoon, and it is in those first windless hours that the mountain reflects.
Pull fully off the road and kill your headlights — a red torch keeps your night vision, and give your eyes a good twenty minutes before judging the sky.
Keep off the braided riverbeds — the grey shingle of the Tasman River looks like empty gravel but is kakī nesting ground, and the eggs are almost invisible underfoot.
The basin funnels a hard nor'wester — it can turn a mirror lake to whitecaps within the hour, so layer up and take real care opening car doors on the highway verge.

Things to do

1
Catch Aoraki doubled in the water at the lookout
From the State Highway 8 lookout at the lake's northern end, Aoraki/Mount Cook lines up head-on down the axis of the valley. Get there before the wind wakes up and the whole 3,724-metre peak lies inverted in a sheet of motionless milk-turquoise.
2
Stand in the lupins that should not be here
For a few weeks from late November the eastern arm and the road verges erupt in purple and pink Russell lupins. It is the picture that made the Mackenzie famous, and it is also a problem: these are garden plants gone wild, and they smother the bare gravel riverbeds where the black stilt, or kakī, has to nest.
3
Drive State Highway 80 to the foot of the mountain
The road runs fifty-odd kilometres up the western shore with the turquoise on your right the whole way. Aoraki grows in the windscreen the entire drive, until the golden tussock of the basin runs straight into the snow wall of the Alps.
4
Cup the rock flour in your hands
Walk down to the shingle and scoop up a handful. Water that looks like opaque paint from the lookout turns out to be almost clear in your palm — the colour lives in the depth, in glacier-ground dust so fine it never settles out.
5
Find the Milky Way's core over the lake
Lake Pukaki sits inside a dark-sky reserve rated gold, the top grade given for how little artificial light reaches the sky. On winter nights the bright centre of our galaxy stands high above the water instead of sitting low on the horizon. Let your eyes adapt for twenty minutes and the Magellanic Clouds, two neighbouring galaxies, surface as well.

Watch

Nearby

46 km