If I were you I would choose 1 and 4 !
The first, third, and fourth.
I know that you said 'opening line', but I found all of that information kind of hard to fit into a handful of sentences. As a result, what I've written might really differ from your perceptions of the story. I hope that it's not too different and that it works for you. Good luck.
The bridge cost to much to build... hope this helps