Editing Three Gorges Dam (section)

== Navigating the dam ==
=== Locks ===
[[File:Three gorges dam locks view from vantage point.jpg|thumb|Ship locks for river traffic to bypass the Three Gorges Dam, May 2004]]
[[File:TGP ship locksat Yangtse River.jpg|thumb|Construction of TGP ship locks at Yangtze River, September 1996]]
[[File:Three Gorges dam locks and bridge.jpg|thumb|The other end of Three Gorges Dam lock. Note the bridge in the background.]]
The installation of [[Lock (water navigation)|ship locks]] is intended to increase river shipping from ten&nbsp;million to 100&nbsp;million tonnes annually; as a result transportation costs will be cut between 30 and 37%. Shipping will become safer, since the gorges are notoriously dangerous to navigate.<ref name="Xinhuar2007023" />

There are two series of ship locks installed near the dam ({{coord|30|50|12|N|111|1|10|E|display=inline|region:CN-62_type:landmark}}). Each of them is made up of five stages, with transit time at around four hours. Maximum vessel size is 10,000&nbsp;tons.<ref>{{cite news | url=http://www.chinaeconomicreview.com/logistics/?cat=88 | title=Yangtze as a vital logistics aid | work=China Economic Review | date=May 30, 2007 | access-date=June 3, 2007 | language=zh | archive-url=https://web.archive.org/web/20100807124521/http://www.chinaeconomicreview.com/logistics/?cat=88 | archive-date=August 7, 2010 | url-status=dead}}</ref> The locks are 280&nbsp;m long, 35&nbsp;m wide, and 5&nbsp;m deep (918 × 114 × 16.4&nbsp;ft).<ref name="Moafs20020420">{{cite web | url=http://www.moafs.org/newsletter/April%202002/3gorgestats.htm | title=Three Gorges Dam | publisher=Missouri Chapter American Fisheries Society | date=April 20, 2002 | access-date=November 23, 2010 | archive-url=https://web.archive.org/web/20081118193954/http://www.moafs.org/newsletter/April%202002/3gorgestats.htm | archive-date=November 18, 2008 | df=mdy | url-status=dead}}</ref><ref>{{cite web | df=mdy | url=http://www.ctgpc.com/benefifs/benefifs_a_5.htm | title=Its Buildings with Biggest Indices | publisher=China Three Gorges Project | access-date=November 23, 2010 | url-status=dead | year=2002 | archive-url=https://web.archive.org/web/20081121012426/http://www.ctgpc.com/benefifs/benefifs_a_5.htm | archive-date=November 21, 2008}}</ref> That is {{cvt|30|m}} longer than those on the [[St Lawrence Seaway]], but half as deep. Before the dam was constructed, the maximum freight capacity at the Three Gorges site was 18.0&nbsp;million tonnes per year. From 2004 to 2007, a total of 198&nbsp;million tonnes of freight passed through the locks. The freight capacity of the river increased six&nbsp;times and the cost of shipping was reduced by 25%. Originally, the total capacity of the ship locks was expected to reach 100&nbsp;million tonnes per year.<ref name=Xinhuar2007023 /> In 2022, their cargo turnover reached 159.65 million tons, with an annual increase of 6% over the previous few years.<ref name=Xinhuar20230222>{{cite web
|url         = https://english.news.cn/20230102/b41207d27e18409bbf0e47637e79e0a3/c.html
|title       = Shipping throughput of Three Gorges Dam hits new record
|publisher   = Xinhua – China, World, Business, Sports, Photos and Video English
|access-date  = February 22, 2023
}}</ref>

These locks are [[Lock gates#Special cases|staircase locks]], whereby inner lock gate pairs serve as both the upper gate of the chamber below and the lower gate of the chamber above. The [[Lock gates#Variations|gates]] are the vulnerable hinged type, which, if damaged, could temporarily render the entire flight unusable. As there are separate sets of locks for upstream and downstream traffic, this system is more water efficient than bi-directional staircase locks.

=== Ship lift ===
{{Anchor|shiplift}}
[[File:Three Gorges Dam (12280456164).jpg|thumb|The ''ship lift'', a kind of elevator, can lift vessels of up to 3,000 tonnes in a fraction of the time required to transit the staircase locks.]]
In addition to the canal locks, there is a [[Boat lift|ship lift]], a kind of elevator for vessels. The ship lift can lift ships of up to 3,000&nbsp;tons.<ref name=shipcom /><ref name="Bbc2005050">{{cite news | df=mdy | url=http://news.bbc.co.uk/2/hi/business/4512015.stm | title=China's west seeks to impress investors | publisher=BBC | date=May 4, 2005 | access-date=November 23, 2010 | last=MacKie | first=Nick | archive-url=https://web.archive.org/web/20081124143445/http://news.bbc.co.uk/2/hi/business/4512015.stm | archive-date=November 24, 2008 | url-status=live}}</ref> The vertical distance traveled is {{cvt|113|m}},<ref name="ChinaThreeGorgesProject">{{cite web | url=http://www.ctgpc.com/benefifs/benefifs_a_5.htm | title=Its Buildings with Biggest Indices | publisher=China Three Gorges Project | access-date=November 23, 2010 | year=2002 | archive-url=https://web.archive.org/web/20131023064744/http://www.ctgpc.com/benefifs/benefifs_a_5.htm | archive-date=October 23, 2013 | url-status=dead}}</ref> and the size of the ship lift's basin is {{cvt|120|x|18|x|3.5|m}}. The ship lift takes 30 to 40 minutes to transit, as opposed to the three to four hours for stepping through the locks.<ref name="Bbc050504">{{cite news | archive-date=November 24, 2008 | archive-url=https://web.archive.org/web/20081124143445/http://news.bbc.co.uk/2/hi/business/4512015.stm | url=http://news.bbc.co.uk/2/hi/business/4512015.stm | title=China's west seeks to impress investors | publisher=BBC | date=May 4, 2005 | access-date=November 23, 2010 | last=MacKie | first=Nick | url-status=live}}</ref> One complicating factor is that the water level can vary dramatically. The ship lift must work even if water levels vary by {{cvt|12|m}} on the lower side, and {{cvt|30|m}} on the upper side.

The ship lift's design uses a helical gear system, to climb or descend a toothed rack.<ref name=Lahmeyer2013 />

The ship lift was not yet complete when the rest of the project was officially opened on May 20, 2006.<ref name="TaipeiTimes20080521">{{cite news | url=http://www.taipeitimes.com/News/world/archives/2006/05/21/2003309291 | title=Three Gorges Dam ready to go | url-status=dead | work=The Taipei Times | date=May 21, 2006 | access-date=November 23, 2010 | archive-url=https://web.archive.org/web/20081203124020/http://www.taipeitimes.com/News/world/archives/2006/05/21/2003309291 | archive-date=December 3, 2008 | df=mdy}}</ref><ref name="CbsNews20060520">{{cite news | url=https://www.cbsnews.com/news/china-completes-three-gorges-dam/ | title=China Completes Three Gorges Dam | publisher=[[CBS News]] | date=May 20, 2006 | access-date=November 23, 2010 | archive-url=https://web.archive.org/web/20080718234115/http://www.cbsnews.com/stories/2006/05/20/world/main1638180.shtml | archive-date=July 18, 2008 | df=mdy | url-status=live}}</ref>
In November 2007, it was reported in the local media that construction of the ship lift started in October 2007.<ref name="CnHubei20071110">{{cite news | archive-date=December 7, 2008 | archive-url=https://web.archive.org/web/20081207035944/http://news.cnhubei.com/hbrb/hbrbsglk/hbrb01/200711/t136849.shtml | url=http://news.cnhubei.com/hbrb/hbrbsglk/hbrb01/200711/t136849.shtml | language=zh | script-title=zh:三峡升船机开工建设_荆楚网 | publisher=CnHubei | date=November 10, 2007 | access-date=August 9, 2008 | trans-title=Three Gorges ship lift operation construction | url-status=dead}}</ref>

In February 2012, ''[[Xinhua]]'' reported that the four towers intended to support the ship lift were nearly complete.<ref name="Xinhua2012-02-27">{{cite news | url=http://english.peopledaily.com.cn/90882/7741118.html | title=Tower columns for Three Gorges shiplift to be built | agency=[[Xinhua News Agency]] | date=February 27, 2012 | location=Yichang, Hubei Province | archive-url=https://web.archive.org/web/20130927235122/http://english.peopledaily.com.cn/90882/7741118.html | archive-date=September 27, 2013 | quote=The entire shiplift will be completed in 2015. | url-status=dead}}</ref> The report said that by that time, the towers had reached {{cvt|189|m}} of the anticipated {{cvt|195|m}}.

As of May 2014, the ship lift was expected to be completed by July 2015.<ref>{{cite web | archive-date=October 16, 2015 | archive-url=https://web.archive.org/web/20151016110932/http://www.scmp.com/news/china/article/1519185/three-gorges-dam-exceeds-cargo-target-set-2030 | url=http://www.scmp.com/news/china/article/1519185/three-gorges-dam-exceeds-cargo-target-set-2030 | title=Three Gorges Dam exceeds cargo target set for 2030 | work=South China Morning Post | date=May 23, 2014 | access-date=October 12, 2015 | url-status=live}}</ref> It was tested in December 2015 and announced complete in January 2016.<ref name=shipcom /><ref name=ChinaEconomicNet2016-02-17 /> [[Lahmeyer]], the German firm that designed the ship lift, said it will take a vessel less than an hour to transit the lift.<ref name=Lahmeyer2013 /> An article in Steel Construction says the actual time of the lift will be 21 minutes.<ref name=SteelConstruction2009 /> It says that the expected dimensions of the {{convert|3000|tonne|e6kg|0|abbr=unit}} passenger vessels the ship lift's basin was designed to carry will be {{convert|84.5|x|17.2|x|2.65|m}}. The moving mass (including counterweights) is 34,000 tonnes.

The trials of elevator finished in July 2016, the first cargo ship was lifted on July 15; the lift time comprised 8 minutes.<ref name="slt1">{{cite news | url=http://www.ctgpc.com/news/news1.php?NewsId=96484 | title=Phase I Field Trial of Ship Lift at Three Gorges Dam Successfully Ends | publisher=China Three Gorges Project | date=August 14, 2016 | access-date=August 14, 2016 | language=en | archive-url=https://archive.today/20160814114620/http://www.ctgpc.com/news/news1.php?NewsId=96484 | archive-date=August 14, 2016 | df=mdy-all | url-status=dead }}</ref> ''[[Shanghai Daily]]'' reported that the first operational use of the lift was on September 18, 2016, when limited "operational testing" of the lift began.<ref name=ShanghaiDaily2016-09-18 />

=== Portage railways ===
Plans also exist for the construction of short [[portage railway]]s bypassing the dam area altogether. Two short rail lines, one on each side of the river, are to be constructed. The {{convert|88|km|mi|adj=mid|-long}} northern portage railway ({{lang|zh|北岸翻坝铁路}}) will run from the [[Taipingxi]] port facility ({{lang|zh|太平溪港}}) on the northern side of the Yangtze, just upstream from the dam, via [[Yichang East Railway Station]] to the Baiyang Tianjiahe port facility in Baiyang Town ([[:zh:白洋镇|白洋镇]]), below Yichang.<ref name=mayor /> The {{convert|95|km|mi|adj=mid|-long}} southern portage railway ({{lang|zh|南岸翻坝铁路}}) will run from [[Maoping, Hubei|Maoping]] (upstream of the dam) via [[Yichang South Railway Station]] to [[Zhicheng]] (on the [[Jiaozuo–Liuzhou Railway]]).<ref name=mayor />

In late 2012, preliminary work started along both future railway routes.<ref name=Qq2012-10-12 />