I spotted a beaver lodge on a lake a couple of days ago. It was large, & very messy; weeds & sticks all slapped together with a ton of mud, but it was amazing that an animal without thumbs could build anything like that. Beavers usually live in a lodge with their mate, & around 3 offspring, called pups, kits, or kittens.
Oh how exciting! I have only seen a live Beaver once and that was in a suburban creek near Sacramento, CA. You are lucky!