Drysuits

Dress for the swim

You paddle in the water, not on it. If you'd be cold swimming in it, you need a drysuit or a good wetsuit.

The layers

base      merino or synthetic
mid       fleece, more in cold water
outer     drysuit, sealed at wrists/neck
feet      booties, never cotton

The rule

Cold shock kills faster than rapids. Dress for immersion, and the river stops being a threat and becomes a ride.