https://steamcommunity.com/app/892970/discussions/0/3104638448271426904/

EDIT: Also, the pieces under water will not degrade past 1, so as long as no outside forces damage them there's not really a reason to fret too much over it. Hoping they do something to fix this though, it's quite annoying to have single pole platform on the sides of my bridge just so I can reach the support poles to repair them.