Talked with Des Moines Marina yesterday. I was told that because they are focusing more on the parking lot, noone asked when the ramp would be open for use (with out the floats of coarse). The floating breakwater will be installed at a later date (possibly mid-Nov.), which will shut the ramp done for several days.
I would suggest that the more people who call and ask about the reopening of the ramp, the sooner it will become available. You can reach the resident engineer(I believe his name is Joe) at the Des Moines Marina @206-824-5700. My exxperience with construction projects is that usually without a little coaxing, things will drag out forever.