There are three major reefs running parallel to shore in SEFL (inner, middle, outer). The first two were dredged long ago to make the current channel, but the third, because of its depth, wasn't impacted as much. It is this third reef that will be impacted the most by this project.
I was part of the team that surveyed the coral communities growing in the channel between the inner and outer reefs, and honestly there wasn't a lot there. The bottom was mostly unconsolidated rubble (baseball to basketball sized), which keeps reef communities from establishing. IMO they should incorporate an element of rubble stabilization in the channel after dredging (or dredge it deeper and then dump very large boulders such as those used in reef mitigation). This would allow new reef communities to develop in the channel, rather than it remaining as rubble.