The draw of the S82 bridge, mile 7.1 at Grand Chenier, shall open on signal; except that, from 6 p.m. to 6 a.m. the draw shall open on signal if at least 4 hours notice is given. During the advance notice period, the draw will open on less than 4 hours notice for an emergency and will open on demand should a temporary surge in waterway traffic occur.
33 C.F.R. §117.480