Rebar corrosion ON the environment

[k9k2j2]

Rebar and concrete was dumped into a river 50 years ago.
There are environmental concerns (water quality and fish habitat) about corrosion of rebar and also concrete in general.

is this concern legitimate?

 

[Metalguy]

Uh, if there were a concern, we'd have to change out a lot of bridge supports!

 

[GGedge]

Not really as simple as Metalguy makes out.

If the stuff has been dumped in the river then it very possible that large areas of reinforcement steel are actually exposed directly to the water. This is not normally the case with reinforced concrete structures. Steel that is exposed to the water will corrode, although perhaps at slower rate than you might expect. Whether this corrosion is detrimental to the environment is difficult to say, most of the iron will remain on the surface as rust. If gets knocked off or detached it will not dissovle and could locally accumulate.