This maintenance is part of a year long project begun in July, see LNM: Upcoming Maintenance. And as past experience has taught, you may expect changes in these announced dates. The Alligator River Bridge crosses the Alligator River section of the Waterway at Statute Mile 84, south of flashing marker #12, just south of where the Waterway exits Albemarle Sound. See also https://cruisersnet.net/168174. Our thanks to George Barr for this update.
Looks like the Alligator River Bridge work is not complete yet. New closing in January as follows:
“Alligator River Bridge on U.S. 64 to Close for Repairs Jan. 10-17
Traffic will be detoured to N.C. 94, U.S. 264, U.S. 17, and U.S. 158
And this link from outerbanksvoice.com: