33 C.F.R. § 117.887
The draw of the Burlington Northern Santa Fe railroad bridge, mile 3.2 at Portland, shall open on signal if at least one half hours notice is given.
[CGD 82-025, 49 FR 17452, Apr. 24, 1984, as amended by CGD13 84-13, 49 FR 35627, Sept. 11, 1984]