It's unreasonable to hold the original engineer responsible for changes after construction that should require review/stamp/signature from another engineer, suc

It's unreasonable to hold the original engineer responsible for changes after construction that should require review/stamp/signature from another engineer, such as increasing the depth of the pavement on the roadway. If the bridge didn't meet the code at the time it was built, that's one thing. But that's not the case here. Also, the private engineering firm likely had nothing to do with the maintenance of the bridge after construction -- That's the job of the state DOT and whoever they contract out to. There's a lot of knowledge and experience in State DOTs, they'll do some bridges in house, some they contract out for. (WA state, states may vary, depends on budgeting conditions and workload.) The older engineers there are generally really smart, and have been doing it for a long time. In stark contrast to the computer industry, experience really does mean something.