Hi Thomas!
Maybe your project will rise the interest of some river enthusiast such as Roberto "Kilo" Chilosi.
He his a rafting guide, a world famous kayaker and also a pretty good hydrospeeder... :-))
He knows very well Valsesia River thought maybe he has some problems with english... :-)))
But he really his the right person you are looking for....
;-)
best regards
Marcone