The pond is considered a red penalty area. Your options for relief are found How to take Relief from a Red Penalty Area under the Rules of Play section of the website.
The bridges are considered in the penalty area. Balls coming to rest on the bridges should be played as if in the penalty area.
Balls touching the metal edging are considered to be in the penalty area.
Swing relief is provided for the metal rods connected to the metal edging that may be exposed above ground.