RAPIDS
(the Estonian rapids) are dangerous when you are not experienced enough yet. The
current in rapids is unbelievably fast and strong and you won't be able to walk
in or through them even when the water is just knee-high. That's why it's sensible
to start canoeing on a pre-prepared river with a guide.
HIGH
WATER is dangerous, because there's much of it and it is fast and strong.
Generally the water is high in spring and after hard rain, but there are no general
rules and everything depends on the river. On some small rivers it's wonderful
with high water, as they are just wider and not dangerous at all.