A Department of Conservation ranger's been penalised after colliding the jet boat he was driving with a kayaker on the Whanganui River

In November last year, Wanihi Butler crashed into the kayaker, who was tipped into the river and suffered multiple injuries to their ribs, lungs and shoulders.

Maritime NZ says Butler didn't maintain a proper lookout, or give way to the kayaker travelling downstream.

He was ordered to pay just over 10-thousand dollars of reparation.