Actually, I think you've got a very nice abstract in there... if you lose everything except the two contrasting colours of the water. As it stands it's a very good record shot... but if you lose the top of the frame, I can easily see it as the cover shot of a book/magazine on pollution.
Definitely a keeper and one for the stock library!
I actually tried cropping out the drain walls (ie just the two contrasting colours), but it became difficult to tell what the picture was about. I finally decided on keeping the drain outlet within the frame so as to give a clue.