thank you @ana-maria and you are absolutely right. Winning a nondescript tournament means nothing (although doing something extraordinary like doing 49k steps on working day - while my long term average is just about 20k - does matter to me). You've captured the important thing. Look at the satellite view:

The pin denotes the place where I spotted traces of beavers activity. South to it you see a green area - it's a city park (photo with a wooden beaver sculpture in my original post). The lakes to the north-east are artificial. Sand had been extracted to replace depleted coal in nearby mines (now closed) and the pits had been flooded. To the east, you will see a huge steelworks complex (far right-hand side of the photo, between S1 and 94 roads). If you look west - there's a coal-powered electro-plant. Look south and you see densely populated area. You would think - the is the last of places where beavers would live. Yet, wise re-cultivation and management made it possible. True, the beavers cannot do as they please - bigger trees are protected, wooden sticks in the river bottom prevent them from digging holes in places where it would have posed danger to nearby neighborhood. But within the limits, they do well. And we, humans, can enjoy "green lungs" of otherwise industrial (or post-industrial, as some mines/plants have been shut down) area.