Water feature Harbor; with trap door; using my LIONEL Swing bridge

I would suggest a Google search for pictures of real swing bridges to see how they appear anchored in water. Then I'd determine how I'd mount the bridge. 

I think you’re going to need a big hole to get up past that bridge. 

John H posted:

I think you’re going to need a big hole to get up past that bridge. 

Is this a big enough hole?   Really now. The bridge will be in place on the mainline, the trap or swing door will be after the bridge and swing either to the side, or towards the back in this picture. The seam, if there is one, will be hidden by the bridge structure when looking at it from the location in the picture.

Anyone with ideas, who did a drop in a water scene??

Dumb me.

"a trap door, not a pop out, that will swing down and out of the way, so I can get into the layout for any problems, like derailments. We are installing my LIONEL swing bridge to this situation. "

I took it to mean the bridge was on the door.

What if you put wheels on that section and rolled it out?

A roll out would be an interesting idea,