Originally Posted by evergrn

I think Onuma will be good for that, although there may not be a beach per se along the lake.
It's a nice area, and you should be able to rent canoes/kayaks there.

As far as beaches, though, Hakodate has a beach area called Nanaehama (had to look it up). It doesn't look that great to me, though.

I too love Noboribetsu, so much so that I first went in 2015 and have already been close to 10x since. But I do understand the hassle of changing hotels.