re: “…turbid water comes from the Arve river, which is full of silt…”

Geologists call it Glacier Milk, on occasion.

Dan Kurt

Lack of lateral mixing between two merging rivers is more or less standard. The two (sometimes three or more) streams can flow side-by-side for surprising distances, sometimes 100 miles, before encountering a turbulent zone (often a rapids) that forces the mixing.

The lack of lateral mixing is usually not obvious to the naked eye, as in this case, and requires chemical analysis. Fish often detect the differences.

Hmm, looks like dirty liberal water and clean conservative water to me.

I wish the clear stream were larger.

It’s like Mark Steyn says, it only takes a small spoon of dog shit in a quart of ice cream to make the whole thing inedible.