Place dams to guide the river, balancing trade and ecology.
Dam five river deltas to protect their ecosystems while transporting hazelnuts downstream.
In each level you gain points, after five levels you see your final score.
The landscape has several heights, going down from left to right. The arrows along the river beds indicate which way the river can flow. Dams always block flow through a river bed.
An ecosystem is indicated by a beaver, and surrounded by a triangle. The vertices of these triangles are ponds which are either wet or dry, depending on whether the river flows into them. The rate at which the water level changes depends on how many ponds are wet/dry.
Super original game! I like the concept of having to balance the flows so that things get neither too wet nor too dry, but I think it's a bit hard to understand at first. A 3D view would help clarify the depth aspect of it. Or perhaps showing fewer arrows on rivers with a shallower slope. Then you wouldn't even need to draw the Voronoi cells anymore.
To make it easier to understand, you could have floating score bubbles pop out whenever something affects your score: a periodic +1 from every happy beaver, and a periodic -1 for every dam, for example. It would make things a bit more cluttered though.
Instead of aiming for the highest score, you could also make the objective to survive for as long as possible. This is more "binary" and thus also a bit easier to understand. An upset beaver would start a countdown and end the game after 5-10 seconds, and a particular number of lost hazelnuts would end the game too. However, you would have to find a way to increase difficulty smoothly over time.
Did you consider making it turn based instead? That might just be my personal pet peeve, but if a game calls for strategic decisions, I like to have the time to think them through. Now, as often as not, it's a matter of being able to click quickly enough to block a hazelnut from falling into the sea before the ship comes back.
This is quite a unique one. There is a lot going on here and understanding all the details took me quite some time.
If you want to continue working on your game, I suggest to add a tutorial that gradually introduces and explains the different mechanics in game. Tooltips would also be a great idea!
Overall this would be a prime candidate for an alakajam Tournament game. Really enjoyable!