Dot Yacht's got moorings for 160+ boats, which is a pretty substantial amount of traffic. Way more than a "few dozen members". While most of the boats are slim-profile enough to slip under the bridge in the closed position making openings not too frequent a traffic snarl, on utilization there's no way you can look Day Basin maritime traffic in the face and say the draw is unnecessary or needs to go for the betterment of car traffic. If that isn't a busy enough waterway to traffic-share an inlet, what is?With these situations right of way falls to who was there first. Since the water was there first they have right of way. I found this out reading about the portal bridge on the northeast corridor that has to also raise for boats and backs up the trains. Thats why in that case theyre building a taller fixed bridge.
And it's not like you can raise Morrissey all that much more to make for a fixed bridge. There's already a plenty stiff upgrade coming out from under the 93 overpass. Going taller may be in the realm of feasibility, but the end result would be one hella steep hill with a high-speed offramp merge at its steepest slope so there are a whole lot of other road-design problems with this stretch of MDC-era dysfunctionway more pressing for troubleshoots as first order of business than prioritizing a maximally fugly kludge around the draw.