That bridge was, if memory serves, poorly designed (albeit under supervision of our Pacific Axis partners), it didn't last very long.
Err.. technically speaking, it's still there, albeit over a river that is not named Kwai (there isn't one) and the film, the Railway Man (out next year) details some of this...
There are two classic modern titles (a friend got the author of one to sign a copy for me) on that bridge, and some friends have visited
the site - the oddest bit was how close the stories ran, and that they both waited until the twilight of their lives (one has now passed) - the both had the following parallels... Singapore at the fall, Changi prison, the Death Railway (Kwai), the Death March, the Hell ships, being torpedoed by USofA subs and being rescued, if you could call it, by other Hell ships, making it to Japan, and witnessing Nagasaki, first hand... the book I have, the Forgotten Highlander, brings tears to the eyes; a more harrowing single account of war I have never read; combined books on Japanese war crimes are medieval in their barbarity...