Fix potholes, repaint every decade or so, and check for loose nuts. It's what we do with 99.99% of the bridges in this country.
It doesn't cost that much.
...uh...does the word earthquake mean anything to you??!! Those cars that went off the middle of the Bay Bridge in '89 sure weren't happy about the lack of retro-fitting....
but hey.......I"ve been over most of the major bridges in the US except for the Florida Keys and HEEEEEEYYYYYYYY, this is the Golden Gate for crying out loud....I still get goose bumps sometimes coming in from Marin, fog coming over the bridge and you can only see the tallest buildings in SF in the morning fog.........now there is a $6 site.....beats all the rest of them.....awesome........LOL.....just kidding