Wow, your photo of the arches sure brings back memories. In the late 50's, early 60's, I used to go fishing at Carr Mill, with a bunch of scallywags from Norris Green. 3 busses and a lot of walking would get us to the arches by lunch time, but we had no money left for lunch, just enough for the ride home, boo hoo!
For all the fishing I did, the only time in my life that I ever caught one was from right there where you captured that image. Took it home in an old bait can and gave it a new home in an old wash tub. It was probably the soap residue in the tub that killed it. Plus I don't remember actually feeding it.
The power boats were something special, just a massive engine with enough of a hull around them to keep them afloat, not always successfully!
For all the times we went there, we never did actually get to see any damn dam, it was so well fenced off that it defeated even Norris Green scallywags.