Panama Canal

===Capacity===
The canal handles more vessel traffic than had ever been envisioned by its builders. In 1934 it was estimated that the maximum capacity of the canal would be around 80 million tons per year;<ref>{{Cite book |url=http://www.czimages.com/CZMemories/thirdlocks/tlpage3.htm |title=The Land Divided—A History of the Panama Canal and other Isthmian Canal Projects |first=Gerstle |last=Mack |year=1944 |access-date=January 7, 2006 |archive-date=May 1, 2013 |archive-url=https://web.archive.org/web/20130501112749/http://www.czimages.com/CZMemories/thirdlocks/tlpage3.htm |url-status=live }}</ref> as noted above, canal traffic in 2015 reached 340.8 million tons of shipping.

To improve capacity, a number of improvements have been made to maximize the use of the locking system:<ref name="3rdLockProposal">
{{cite web |url=http://www.acp.gob.pa/eng/plan/documentos/propuesta/acp-expansion-proposal.pdf |title=Proposal for the Expansion of the Panama Canal |date=24 April 2006 |publisher=Panama Canal Authority |url-status=dead |archive-url=https://web.archive.org/web/20110721055325/http://www.acp.gob.pa/eng/plan/documentos/propuesta/acp-expansion-proposal.pdf |archive-date=2011-07-21 |page=45}}
</ref>
* Implementation of an enhanced locks lighting system;
* Construction of two tie-up stations in Culebra Cut;
* Widening Culebra Cut from {{convert|192|to|218|m|ft|sp=us}};
* Improvements to the tugboat fleet;
* Implementation of the carousel lockage system in Gatun locks;
* Development of an improved vessel scheduling system;
* Deepening of Gatun Lake navigational channels from {{convert|10.4|to|11.3|m|ft|sp=us}} PLD;
* Modification of all locks structures to allow an additional draft of about {{convert|1|ft|m|sp=us|order=flip}};
* Deepening of the Pacific and Atlantic entrances;
* Construction of a new spillway in Gatun, for flood control.
These improvements enlarged the capacity from 300 million PCUMS (2008) to 340 PCUMS (2012). These improvements were started before the new locks project, and are complementary to it.