I had an easier time getting back into New Orleans from the state park than I had getting to the park last night, because the road had a paved ditch most of the way, and I was able to ride in that. I took a different ferry that went straight downtown from Algiers, where many of the Mardi Gras floats are made.
I rode into downtown on Canal Street, which is a wide boulevard with streetcar tracks down the center. I saw another bicyclist riding down the streetcar right-of-way, so I tried that and found it much easier than riding in the lanes of traffic.