Section 117.605 - Merrimack River(a) The draw of the Newburyport US1 Bridge, mile 3.4, shall operate as follows:(1) From May 1 through November 15, from 6 a.m. to 10 p.m., the draw shall open on signal; except that, from Memorial Day through Labor Day, from 6 a.m. to 10 p.m., the draw shall open on signal only on the hour and half hour.(2) At all other times the draw shall open on signal after at least a one-hour advance notice is given by calling the number posted at the bridge.(b) The drawspans for the Massachusetts Department of Transportation drawbridges, mile 5.8 at Newburyport and mile 12.6 at Rock Village, and Groveland Drawbridge, mile 16.5 at Groveland, must open on signal if at least two hours notice is given. Public vessels of the United States must be passed through the drawspans as soon as possible.CGD 82-025, 49 FR 17452, Apr. 24, 1984, as amended by CGD01-94-094, 60 FR 58518, Nov. 28, 1995; CGD01-99-029, 65 FR 24640, Apr. 27, 2000; USCG-2001-10881, 71 FR 70311, Dec. 4, 2006; USCG-2015-0433, 80 FR 44281, July 27, 2015; USCG-2018-0443, 83 FR 30039, June 27, 2018 USCG-2018-0443, 83 FR 30039, 6/27/2018