Great photo, they have clearly started to expose the 'piles' on west (left) side in preparation for eventual removal and I think they said that if there is a bit of leakage now it does not matter as the river and lake are now at same level so water will not flood in (or out) should a breach occur. I think the north plug is due to be removed next spring - presumably so that the debris area upstream can be finished and catch some or all of the 'crap' before it hits the new river and gets into the Lake. They may also want to finish the dredging of the Keating Channel - which is scheduled to start when the final bits of the old Cherry St bridge are gone.