Love the principle!
Got an unfortunate bug where I had a tornado shamble everything and put an obstacle in front of a road, at the only place where I could have built a connexion, so I couldn't start the waves anymore :(
But overall I had fun playing it, good ambiance, nice graphics and cool mechanic. Very well done!
EDIT:
Ah, I can erase obstacles with the trash icon. But there is also the eraser option which didn't do anything, a bit confused why we have both 😅