upperreach
Upperreach is a term that can refer to more than one concept. In hydrology and river geography, the upper reach denotes the upstream portion of a river or stream, typically extending from the source or headwaters to a downstream point where the channel broadens or becomes a lower-reach segment. This portion of a river often features steeper gradients, cooler water, and higher variability in discharge, and it is a focus area for watershed management, habitat assessment, and flood forecasting.
As a toponym, Upperreach is used as the name of fictional towns or settlements in various works
Etymology: the term combines “upper,” indicating a positional modifier, with “reach,” a technical term for a stretch