This was a nicely made game with a good take on theme and limitation. Controls were fine and took a minute and was a little off putting going of screen (at the start of the water flow).
Main though is sounds would have made this 100% better and music less important but also would have added a lot.
I played for a bit but can see this may have got repetitive without new obstacles or twists and turns in the river. This was done in 72 hours so not saying I expect this just offering some thoughts for if you build it out a little.
Also due to the nature of the game a local or online (better) leaderboard seems necessary to encourage more play.