I dunno, there's a lot more boats that use Karapiro than just ski boats. I hear the limited use in comparison for Okataina though, you aren't going to launch a trailerable gin palace there that easily. Having said that we've chucked some fairly sizeable work barges etc into there.
The limiting factor for closing the lake to fishing is that the trout will start giving the ecosystem a bit of a hard time as well, I'd be surprised if it was to be a permanent thing for that reason alone.
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