From jack and Jude.
Hells Gate, was given that name by convicts being interned on Sarah Island. The name has stuck because Hells Gate lies directly exposed to Southern Ocean swell and the Roaring Forties. It can have extraordinary outpourings of water, which are not based solely on tide, but a combination of wind, atmospheric pressure, and how much water is being released by the Gordon River Power Station.
Best advice: South winds increase flow - North winds lessen it - Heavy rains increase flow. Do not attempt after dark.
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