Editing Moveable bridge (section)

{{Short description|Bridge that moves to allow passage, usually of watercraft}}
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[[File:Madison Street Bridge.JPG|thumb|Madison Street Bridge, a bascule bridge over the [[Chicago River]] in [[Chicago]], IL]]
[[File:De Rode Brug in Utrecht.jpg|thumb|The ''Rode Brug'' (Red Bridge) across the [[Vecht (Utrecht)|Vecht]] river in [[Utrecht]], [[Netherlands]]]]
[[File:B&T 3800 (7337567620).jpg|thumb|The [[Marine Parkway–Gil Hodges Memorial Bridge]] in [[New York City]]]]
A '''moveable bridge''', or '''movable bridge''', is a [[bridge]] that moves to allow passage  for boats<ref>{{Citation |title=Boat |date=2023-04-09 |url=https://en.wikipedia.org/w/index.php?title=Boat&oldid=1148994403 |work=Wikipedia |access-date=2023-05-17 |language=en}}</ref> or barges.<ref>Schneider, C.C. (1907) [https://books.google.com/books?id=y60SAAAAYAAJ&dq=movable+bridge&pg=RA1-PA153 "Movable Bridges"], Proceedings of the [[American Society of Civil Engineers]], Volume 33, Part 1, Page 154.</ref> In American English, the term is synonymous with {{em|drawbridge}}, and the latter is the common term, but [[drawbridge]] can be limited to the narrower, historical definition used in some other forms of English, in which ''drawbridge'' refers to only a specific type of moveable bridge often found in castles.

An advantage of making bridges moveable is the lower cost, due to the absence of high piers and long approaches. The principal disadvantage is that the traffic on the bridge must be halted when it is opened for passage of traffic on the waterway. For seldom-used railroad bridges<ref>{{Citation |title=List of road–rail bridges |date=2023-04-15 |url=https://en.wikipedia.org/w/index.php?title=List_of_road%E2%80%93rail_bridges&oldid=1149921151 |work=Wikipedia |access-date=2023-05-17 |language=en}}</ref> over busy channels, the bridge may be left open and then closed for train passages. For small bridges, bridge movement may be enabled without the need for an engine. Some bridges are operated by the users, especially those with a boat, others by a [[bridgeman]] (or [[bridge tender]]); a few are remotely controlled using video-cameras and loudspeakers. Generally, the bridges are powered by electric motors, whether operating winches, gearing, or hydraulic pistons. While moveable bridges in their entirety may be quite long, the length of the moveable portion is restricted by engineering and cost considerations to a few hundred feet.

There are often [[traffic light]]s for the road and water traffic, and moving barriers for the road traffic.

In the [[United States]],<ref>{{Citation |title=United States |date=2023-05-16 |url=https://en.wikipedia.org/w/index.php?title=United_States&oldid=1155132567 |work=Wikipedia |access-date=2023-05-17 |language=en}}</ref> regulations governing the operation of moveable bridges (referred to as ''drawbridges'')<ref name=title33-part117>{{cite web|title=Part 117: Drawbridge Operation Regulations|url=http://www.gpo.gov/fdsys/pkg/CFR-2006-title33-vol1/pdf/CFR-2006-title33-vol1-part117.pdf|work=Title 33, [[Code of Federal Regulations]]|publisher=[[United States Government Printing Office]]|access-date=August 9, 2013|date=July 1, 2006}}</ref>&nbsp;– for example, hours of operation and how much advance notice must be given by water traffic&nbsp;– are listed in [[Title 33 of the Code of Federal Regulations]];<ref>{{cite web |url=http://www.access.gpo.gov/nara/cfr/waisidx_06/33cfr117_06.html |title=2005 CFR Title 33, Volume 1 |publisher=Access.gpo.gov |access-date=2009-12-01 |archive-url=https://web.archive.org/web/20081012035520/http://www.access.gpo.gov/nara/cfr/waisidx_06/33cfr117_06.html |archive-date=2008-10-12 |url-status=dead }}</ref> temporary deviations are published in the [[United States Coast Guard|Coast Guard's]] Local Notice to Mariners.<ref>{{cite web|url=http://www.navcen.uscg.gov/?pageName=lnmMain |title=Local Notice to Mariners – USCG Navigation Center |publisher=[[United States Coast Guard]] |access-date=2009-12-01}}</ref>