You need a licence to drive a vessel for recreational purposes on NSW waters if:
you plan to drive the vessel at 10 knots (18.5 km/h) or more, or
the vessel is a personal watercraft (PWC).
You don't need a licence for:
driving a powerboat under 10 knots, or sailing boat using its engine under 10 knots
sailing a sailing boat without an engine
using paddlecraft such as canoe, kayak or surf ski, or rowing vessels such as a row boat
using a sailboard or kiteboard.
What about commercial use
To operate a vessel for commercial purposes, you need a Certificate of competency.