Placing a decorative bridge over pond - Stain question.

I am building a decorative bridge to go over my pond (not intended for walking across) I am using cedar planks and wanted to stain them. My question is after stain is dry is there any concern I should have during the wet months. (With having the stained cedar over the pond, will it bleed into the pond and be harmful to the fish?) If yes, are there any other ideas?
Thanks!
DC

I do not think the stain would come off....