33 C.F.R. § 117.664
The draw of the Canadian National Railroad Bridge, mile 85.0, at Ranier, MN may operate remotely, and shall open on signal; except that, from October 16 to April 30, the draw shall open on signal if at least 12-hours advance notice is provided. The commercial phone number to provide advance notice shall be posted on the bridge so that it is plainly visible to vessel operators approaching the up or downstream side of the bridge. The owners of the bridge shall provide and keep in good legible condition two board gauges painted white with black figures to indicate the vertical clearance under the closed draw at all water levels. The gauges shall be so placed on the bridge that they are plainly visible to operators of vessels approaching the bridge either up or downstream. The bridge shall operate and maintain a VHF-FM Marine Radio.
33 C.F.R. §117.664