It is head means it transfers water to other canals and sub-canals. This head is directly linked to river.
As beach is almost 1500km away from me so I cannot post photo with it. Although I have visited a waterfall which was Umbrella waterfall but I didn't post that photo as I have used photos in one of my blogs in outdoor and more community. That's why I selected this one.
Ah ok, I wasn't sure what that meant, head. An aqueduct I guess we'd call it.
But here everyone calls it head. Even sign board has the same name. Yes, you are also right.