Poolburn Dam does not have (known) consistent records for freezing but when it does it is a spectacular place to skate.  The track up to the dam in winter can be icy and/or muddy and at times impassible.  Not much is yet known about the quality and consistency of the ice so it pays to treat the dam with respect - and know your safety procedures. My experience has shown the ice can change dramatically over a 24hr period due to the effect of wind, moisture and temperature. Don't assume the next day will be the same. The ice gets covered in snow which can conceal dangerous and changeable ice conditions - not recommended unless you are sure about what you are doing and take adequate safety precautions !  On a fine day the air temperature can warm significantly and weaken the ice. 
That said Poolburn is a fabulous place to skate - islands, bays and rocks to skate around and we have had some of the best natural ice skating days in NZ up there.  As good as it gets on a 'Sensational Poolburn' day.

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