Hi Ray
Being an old plumber, I am guessing that this old drain is of great interest to you. I can appreciate why you want to photograph it and capture as much detail as possible from both the environment around it and the large bridge structure.
My one thought on this image is that in lightening the image you have possibly over brightened it. Most people assume that when we see a bridge, the underside of it is going to be darker than the landscape surrounding it. In this instance though I think you have gone too far in brightening the brick work. Part of the tell-tale to this problem is that the boundary between the brick and the sky is just too dark... it is almost a black smudge.
For you to make this photo just a little more convincing you need to remove that smudge while possibly darkening the overall brickwork some more.
Perhaps one of the most useful questions you can ask when you look at a photo, or are editing it, is, "Am I convinced by what I am seeing". For the moment the answer is no.
Go back to the original file and have another play... I think you can get this looking better.
Cheers,
Anthony