cwatters,
The Canadairs (CL-215 and CL-415) are not "seaplanes", but true amphibians, in the sense, that they also have a landing gear.
That means they can land at an airfield at the end of the day, rather than having to land on water, and be dragged ashore with "beaching gear".
Down here in the South we have a great respect for these guys, flying in very difficult circumstances... forest and brush fires here are often associated with 50+ kts winds. And the fires are more often than not of criminal origin....