117.639—Ontonagon River.
The draw of the S64 bridge, mile 0.2 at Ontonagon, shall open on signal from April 1 through November 15 from 7 a.m. to 11 p.m. and from 11 p.m. to 7 a.m., if at least one hour notice is given. From November 16 through March 31, the draw shall open on signal if at least 24 hours notice is given.