Hello
there is information on kbkv.be
for the rivers behind
this link
, you have to be a member of the Belgian kayak federation and some other things. Otherwise, the police can pick you off the water and other stuff you won't like. People do call the police in this area if they think you shouldn't be there! (and for most of them, there shouldn't be kayakers at all).
this is a link
to the page with links to the different sections on the rules.
this
is the link to the law in Dutch. You will have to check the appendix.
some extracts:
you can paddle the lesse on some parts year round:
1.A.2. Deelstroomgebied van de Lesse
de Lesse vanaf de eerste vaste stuwdam van de Lesse te
Anseremme tot de samenvloeiing met de Maas te
Anseremme.
--> I think this is the touristic part
between octobre 1st and march 15th, you can paddle more:
1.C.2. Deelstroomgebied van de Lesse
de Lesse vanaf de
brug van Barbouillons in Daverdisse tot Chanly
De Lesse vanaf de stuwdam van het watervlak van
Han-sur-Lesse tot stroomopwaarts van de brug van
Houyet
also interesting is the list with minimal water levels at the end of it. This minimum levels are most off the time really minimal. It should be at least a bit higher for fun paddling!
I would really want to urge you not to paddle the closed parts. The law is that you can't paddle anywere in Wallony. There are some exeptions, but this is not standard, so if people (unknowingly) do illegal things, this might ruin it for everyone everywhere.