This is very cool. Understand that you are constrained by the datasets you have available, but still very cool. Just wondering if it would be possible to rever

This is very cool. Understand that you are constrained by the datasets you have available, but still very cool. Just wondering if it would be possible to reverse the track and plot out where a waterway is fed from? I understand this would be a lot more complex and computationally expensive, but when out on a waterway I always find it interesting to think about where the water I'm floating on came from. Again thanks for the work.