What do you call the place that terminates a water channel, as in the image below?
The channel terminates at the concrete wall. What is the name of that? Channel terminator? Channel barrier?
English Language & Usage Stack Exchange is a question and answer site for linguists, etymologists, and serious English language enthusiasts. It only takes a minute to sign up.Sign up to join this community
That structure is a dam, defined by MW as:
a barrier preventing the flow of water or of loose solid materials (such as soil or snow)
As the definition implies, this term applies, not only to (say) large hydroelectric dams or ones holding back a major river, but also to much smaller structures like the one in your photo.
Not a terribly common thing to see, but they do have a name - plug dam.
Plugs may be dead ends, or they may separate salt water from brackish water to mediate old drainage canal intrusion problems.