That's not a crack; that's imperfect consolidation and possibly a cold joint. It looks like they may have put the concrete nozzle at the peak where those two parged joints come together and just left it there while the concrete flowed out. If that's for the basement of a house you should be ok.
Yes, it is for a house. You are right, it is not a crack, it is where one truck was empty and they had to wait for another truck. Sorry, I described it bad in my original post.
That mix was a bit dry to begin with, look at all those bugholes. Still, for a basement wall that's nothing I would outright reject. I'd core it a few times to make sure you got a good bond between the pours and also between the parge and the wall concrete. I've had this happen before were there was little to no bond across the cold joint, but thankfully we had enough rebar crossing the joint that we deemed it sufficient. I imagine this basement wall is too lightly reinforced to be sufficient if there is a lack of bonding.
Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries
