Quote Originally Posted by Redrobes View Post
So providing you come up with something that fits the bill then it would be alright.

I have run a simulation and got it to predict where the rivers would be based on some rainfall. I set it up so that either side of the map was an exit for water. The result is below. The middle part of the map started as a lake and then drained to one side. The middle of the map is an area of confusion so almost anything could have happened and it would have been reasonable.

What was fixed tho is that all the rivers follow the blue lines meaning that they are perpendicular to the contour lines and thus running downhill as fast as it can. Also no rivers crossed the pink lines of the catchment area borders because those lines determine which way water flows. Thats how we can predict where the rivers should be on a map without having to resort to a simulation.

I am attaching a movie in MPG format to show the simulation running. I hope this will show whats going on and why it was fairly easy to predict where the rivers would have been from the height terrain. Though a lake forms in the middle it is unsustainable and one side won out - in this case the right hand side.
Hi Redrobe! I'm still pretty new on this forum, but I'm working my way through as many topics as possible. I just came to this tutorial and I must say I really like it! As a geographer I can confirm every bit of information you give here. When it comes to the quoted post though, I was wondering if perhaps you could tell me the software you used for this simulation. I would be very interested indeed! Especially since I'm looking for a "natural" way to draw rivers in my map.

Many thanks in advance!