Dear Max,
you can find some of the information you are looking for on this site:
http://www.ckfiumi.net/idro/I can give you the following information:
Vallesoana --> I don't know
Val Grande --> Should be ok, maybe too much water. At present it's raining on the snow.
Val d'Aoste --> I don't know. Normally the season there starts later
Val Sesia --> Ok, perfect levels everywhere
even Ticino --> If you mean the Ticino river in Italy, the level is OK, very high (take care). If you mean the Swiss Region of Ticino, take a look at this link:
http://www.hydrodaten.admin.ch/d/index.htm?lang=de. Here you can find Hydrometric levels of all the Swiss rivers.
Ciao,