concrete curing which (eventually) will be under water

[Donn]

I'm just going to take a wild guess: it's ready to go now. Any time after it has set.

I probably shouldn't say this, but ... I don't believe in the tubagod. Really ...

[Ken Herrick]

I'm just going to take a wild guess: it's ready to go now. Any time after it has set.

I probably shouldn't say this, but ... I don't believe in the tubagod. Really ...

THAT will surely provoke. Expect his arrival as soon as he finishes wetting down the concrete!

[bort]

Joe, are you taking the concrete to Virginia with you?

[pete edwards]

We have a bridge being re-built down the street from our house. The creek flooded the day after they poured the concrete. No problems, they carried on.

[NCSUSousa]

Being involved in new construction, I've asked a similar question in the past and got this response from a licensed professional civil engineer:
There's a big misconception with concrete - it's not drying (losing water), it's curing (chemical reaction involving water).
Concrete forms when the chemical reaction occurs between water and the solids in the mix to form new stronger solids. As long as the falling rain doesn't significantly change the surface temperature or wash away any of the solids, it can't do any harm.