Kōrero: Ocean currents and tides

French Pass in the Marlborough Sounds is a narrow gap between headlands through which tides pour. A massive amount of water that has banked up in Tasman Bay gushes back out to Cook Strait once the tide drops, and when the tide rises, it rushes back in. Tidal currents can reach 2 metres per second in this stretch of water, making it very dangerous for ships.