From Limón Bay a ship is raised by Gatún Locks (a set of three) to an elevation 85 ft (25.9 m) above sea level, traverses Gatún Lake, then crosses the Continental Divide through Gaillard (formerly Culebra) Cut and is lowered by Pedro Miguel Lock to Miraflores Lake and then by the Miraflores Locks (a set of two) to sea level. The average tidal range on the Atlantic side is less than a foot (.3 m); that on the Pacific side is 12.6 ft (3.8 m).
Building an interoceanic canal was suggested early in Spanish colonial times. The United States, interested since the late 18th cent. in trading voyages to the coast of the Pacific Northwest, became greatly concerned with plans for a canal after settlers had begun to pour into Oregon and California. Active negotiations led in 1846 to a treaty, by which the republic of New Granada (consisting of present-day Panama and Colombia) granted the United States transit rights across the Isthmus of Panama in return for a guarantee of the neutrality and sovereignty of New Granada.
The isthmus gained more importance after the United States acquired (1848) California and the gold rush began, and the trans-Panama RR was built (1848-55) with U.S. capital. At the same time, interest in an alternate route, the Nicaragua Canal, was strong in both Great Britain and the United States. Rivalry between the two countries was ended by the Clayton-Bulwer Treaty (1850), which guaranteed that neither power should have exclusive rights or threaten the neutrality of an interoceanic route. In the 1870s and 80s the United States tried unsuccessfully to induce Great Britain to abrogate or amend the Clayton-Bulwer Treaty.
After the United States acquired territory in the Caribbean and in the Pacific as a result of the Spanish-American War (1899), U.S. control over an isthmian canal seemed imperative. Following protracted negotiations, a U.S.-British agreement (see Hay-Pauncefote Treaties) was made in 1901, giving the United States the right to build, and by implication fortify, an isthmian canal. It was then necessary for Congress to choose between Nicaragua or Panama as the route for the canal.
Meanwhile a concession for building a sea-level canal in Panama (granted 1878) was acquired by a French company under Ferdinand de Lesseps. Work began in 1881, but poor planning, disease among the workers, construction troubles, and inadequate financing drove the company into bankruptcy in 1889. Amid charges of corruption and mismanagement, French courts transferred (1894) the rights and assets to a new company. Although the alternate Nicaragua route was favored by the United States, an American representative of the French company, William Nelson Cromwell, began working vigorously to interest the United States in the Panama route, and Philippe Bunau-Varilla, a leading figure in the new company, devoted himself to the cause. When a U.S. commission recommended a canal through Nicaragua in 1901, Bunau-Varilla persuaded the French directors to reduce the price of the company's rights, gaining the support of Mark Hanna and later of the new President, Theodore Roosevelt. The commission reversed its recommendation, and Congress authorized purchase of the French company's rights and construction of the Panama Canal.
The Hay-Herrán Treaty, signed (Jan., 1903) with Colombia, would have given the United States a strip of land across the Isthmus of Panama in return for an initial cash payment of $10 million and an annuity of $250,000, but the Colombian senate refused to ratify it. An insurrection, involving Bunau-Varilla and other proponents of the canal as well as the regional population, was encouraged by the United States. Panama rose in revolt on Nov. 3, 1903, declaring itself independent of Colombia. Invoking the treaty of 1846, the United States sent an American warship to Panama, and its presence prevented Colombian troops from quelling the outbreak. The new republic was formally recognized three days later, and on Nov. 17 the Hay-Bunau-Varilla Treaty was signed, granting to the United States, in return for the same terms offered Colombia, exclusive control of a canal zone in perpetuity, other sites necessary for defense, and sanitary control of Panama City and Colón. Colombia's efforts to secure redress for the loss of Panama later resulted in ratification of a treaty (1921) by which the United States paid Colombia $25 million, and Colombia recognized the independence of Panama.
Construction of a lock canal was decided on in 1906. The first three years were spent in the development of construction facilities, surveys, and disease control. The canal was informally opened Aug. 15, 1914; formal dedication took place on July 12, 1920. The total cost was $336,650,000, and c.240 million cu yd (184 million cu m) of earth were evacuated. Madden Dam, which stores additional water for the locks, was completed in 1935.
In 1939 treaty amendments increased Panama's annuity to $434,000 (retroactive to 1934 to offset dollar devaluation), provided for a transisthmian highway, and (at Panama's insistence) abrogated the U.S. guarantee of the neutrality and sovereignty of Panama. Although in the same year Congress authorized construction of a third set of locks, World War II intervened, and the plans were shelved. In 1955 the annuity was raised to $1,930,000, and the United States undertook to build a high-level bridge (completed 1962) over the Pacific side of the canal. The Gaillard Cut was widened in 1969 to permit two-way traffic. The largest modern merchant and fighting ships, however, cannot pass through the canal.
In the 1960s there was increasing agitation in Panama to achieve greater Panamanian control over the canal, resulting in the negotiation of a new treaty (1967) which failed, however, to gain ratification by the Panamanian government. In 1977 negotiations were successful, and a new treaty was signed. It returned the Panama Canal Zone to Panama while setting up joint U.S.-Panamanian control of the canal until the end of 1999, when Panama gained full control. A separate treaty (1979) guarantees the permanent neutrality of the canal. In 0ct., 2006, Panamanian voters approved expanding the canal by adding a third series of locks paralleling the existing locks; the new locks, whose construction was inaugurated in 2007, will be larger, enabling wider, longer vessels with deeper drafts to transit the Isthmus. The plan will utilize the work begun but abandoned on a third series of locks prior to World War II.
See G. W. Goethals, The Panama Canal: An Engineering Treatise (1916); M. P. DuVal, And the Mountains Will Move (1947, repr. 1968); D. G. Payne, The Impossible Dream (1972); J. P. Speller, The Panama Canal (1972); G. H. Summ and T. Kelly, The Good Neighbors: America, Panama, and the 1977 Canal Treaties (1988); A. C. Richard, The Panama Canal in American National Consciousness, 1870-1990 (1990).
Since opening, the canal has been enormously successful, and continues to be a key conduit for international maritime trade. The canal can accommodate vessels from small private yachts up to large commercial vessels. The maximum size of vessel that can use the canal is known as Panamax; an increasing number of modern ships exceed this limit, and are known as post-Panamax or super-Panamax vessels. A typical passage through the canal by a cargo ship takes around nine hours. 14,011 vessels passed through in 2005, with a total capacity of 278.8 million tons, making an average of almost 40 vessels per day.
While the Pacific Ocean is west of the isthmus and the Atlantic to the east, the journey through the canal from the Pacific to the Atlantic is one from east to west. This is a result of a the isthmus's "curving back on itself" in the region of the canal. The Bridge of the Americas at the Pacific end is about a third of a degree of longitude east of the end near Colon on the Atlantic.
The earliest mention of a canal across the Isthmus of Panama dates back to 1534, when Charles V, Holy Roman Emperor and King of Spain, ordered a survey for a route through Panama that would ease the voyage for ships traveling to and from Spain and Peru. During his expedition of 1788–1793 Alessandro Malaspina demonstrated the feasibility of a canal and outlined plans for its construction.
Given the strategic situation of Panama and its narrow isthmus separating two great oceans, other forms of trade links were attempted over the years. The ill-fated Darien scheme was an attempt launched by the Kingdom of Scotland in 1698 to set up an overland trade route, but was defeated by the generally inhospitable conditions, and abandoned two years later in 1700. Finally, the Panama Railway was built across the isthmus, opening in 1855. This overland link greatly facilitated trade and this vital piece of infrastructure was a key factor in the selection of the later canal route.
An all-water route between the oceans was still seen as the ideal solution, and the idea of a canal was enhanced by the success of the Suez Canal. The French, under Ferdinand de Lesseps, began construction on a sea-level canal (i.e., without locks) through what was then Colombia's province of Panama, on January 1, 1880. The French began work in a rush with insufficient prior study of the geology and hydrology of the region. Among other problems, sea level on the Caribbean side of Panama is lower than on the Pacific side. In addition, disease, particularly malaria and yellow fever, sickened and killed vast numbers of employees, ranging from laborers to top directors of the French company. Public health measures were ineffective because the role of the mosquito as a disease vector was then unknown. These conditions made it impossible to maintain an experienced work force as fearful technical employees quickly returned to France. Even the hospitals contributed to the problem, unwittingly providing breeding places for mosquitoes inside the unscreened wards. Actual conditions were hushed-up in France to avoid recruitment problems. In 1893, after a great deal of work, the French scheme was abandoned due to disease and the sheer difficulty of building a sea-level canal, as well as lack of French field experience, such as downpours causing steel equipment to rust. The high toll from disease was one of the major factors in the failure; as many as 21,900 workers are estimated to have died during the main period of French construction (1881–1889).
In 1902, after having run into a 10-cent Nicaraguan postal stamp produced in the US by the American Bank Note Company erroneously depicting a fuming Momotombo volcano (which was nearly dormant and stands more than 160 km (100 miles) from the proposed Nicaraguan canal path) and taking advantage of a particularly volcanic year in the Caribbean, Cromwell planted a story in the New York Sun reporting that the Momotombo volcano had erupted and caused a series of seismic shocks. He thereafter sent leaflets with the above stamps pasted on them to all U.S. Senators as witness to the volcanic activity in Nicaragua. On June 19, 1902, three days after senators received the stamps, they voted for the Panama route for the canal. For his lobbying efforts, Cromwell received the sum of $800,000.
In November 1903, Phillipe Bunau-Varilla, Panama's ambassador to the United States, signed the Hay-Bunau Varilla Treaty, granting rights to the United States to build and indefinitely administer the Panama Canal. Bunau-Varilla, although serving as Panama's ambassador, was a French citizen, and was not authorized to sign treaties on behalf of Panama without the review of the Panamanians. This treaty became a contentious diplomatic issue between the two countries, culminating in riots in which 21 Panamanians and 4 U.S. soldiers were killed on Martyr's Day, January 9, 1964. The issues were resolved with the signing of the Torrijos-Carter Treaties in 1977, returning the former Canal Zone territories to Panama.
The United States, under President Theodore Roosevelt (with John Frank Stevens as Chief Engineer from 1905–1907), bought out the French equipment and excavations for US$40 million, and began work on May 4, 1904, after helping Panama achieve the separation from Colombia by deploying troops and naval forces to prevent Colombia from suppressing the rebellion against Colombian governance, created by the United States of America. The United States paid Colombia $25,000,000 in 1921, seven years after completion of the canal, for redress of President Roosevelt's role in the creation of Panama, and Colombia recognized Panama under the terms of the Thomson-Urrutia Treaty.
Chief Engineer (1905–1907), John Frank Stevens', primary achievement in Panama was in building the infrastructure necessary to complete the canal. He rebuilt the Panama Railway and devised a system for disposing of soil from the excavations by rail. He also built proper housing for canal workers and oversaw extensive sanitation and mosquito-control programmes that eliminated yellow fever and other diseases from the Isthmus. Stevens argued the case against a sea level canal like the French had tried to build. He successfully convinced Theodore Roosevelt of the necessity of a canal built with dams and locks.
A significant investment was made in eliminating disease from the area, particularly yellow fever and malaria, the causes of which had originally been theorized by Cuban physician/scientist Dr. Carlos Finlay in 1881 who had identified the mosquito as the vector that causes the disease and whose theory and investigative work had recently been confirmed by Dr. Walter Reed while in Cuba with U.S. Army motivation during the Spanish-American War (see Health measures during the construction of the Panama Canal). With the diseases under control, and after significant work on preparing the infrastructure, construction of an elevated canal with locks began in earnest and was finally possible. The Americans also gradually replaced the old French equipment with machinery designed for a larger scale of work (such as the giant hydraulic crushers supplied by the Joshua Hendy Iron Works), quickening the pace of construction, President Roosevelt had the former French machinery minted into medals for all workers who spent at least two years on the construction to commemorate their contribution to the building of the canal. These medals featured Roosevelt's likeness on the front, the name of the recipient on one side, and the worker's years of service, as well as a picture of the Culebra Cut on the back.
In 1907 Roosevelt appointed George Washington Goethals as Chief Engineer of the Panama Canal. The building of the canal was completed in 1914, two years ahead of the target date of June 1, 1916. The canal was formally opened on August 15, 1914 with the passage of the cargo ship Ancon. Coincidentally, this was also the same month that fighting in World War I (the Great War) began in Europe. The advances in hygiene resulted in a relatively low death toll during the American construction; still, 5,609 workers died during this period (1904–1914). This brought the total death toll for the construction of the canal to around 27,500.
By the 1930s it was seen that water supply would be an issue for the canal; this prompted the building of the Madden Dam across the Chagres River above Gatun Lake. The dam, completed in 1935, created Madden (later Alajuela) Lake, which acts as additional water storage for the canal. In 1939, construction began on a further major improvement: a new set of locks for the canal, large enough to carry the larger warships which the U.S. had under construction, or planned for future construction. The work proceeded for several years, and significant excavation was carried out on the new approach channels, but the project was canceled after World War II.
After the war, United States' control of the canal and the Canal Zone surrounding it became contentious as relations between Panama and the U.S. became increasingly tense. Many Panamanians felt that the canal zone rightfully belonged to Panama; student protests were met by the fencing in of the zone and an increased military presence. Negotiations toward a new settlement began in 1974, and resulted in the Torrijos-Carter Treaties. Signed by President of the United States Jimmy Carter and Omar Torrijos of Panama on September 7, 1977, this set in motion the process of handing the canal over to Panamanian control for free as long as Panama signed a treaty guaranteeing the permanent neutrality of the canal (Neutrality Treaty) and allowed the U.S. to come back anytime. Though controversial within the U.S., the treaty led to full Panamanian control effective at noon on December 31, 1999, and control of the canal was handed over to the Panama Canal Authority (ACP).
Before this handover, the government of Panama held an international bid to negotiate a 25-year contract for operation of the canal's container shipping ports (chiefly two facilities at the Atlantic and Pacific outlets), which was won by the firm Hutchison Whampoa, a Hong Kong-based shipping concern whose owner, Li Ka Shing, is the wealthiest man of Chinese descent in the world.
The canal consists of artificial lakes, several improved and artificial channels, and three sets of locks. An additional artificial lake, Alajuela Lake (known during the American era as Madden Lake), acts as a reservoir for the canal. The layout of the canal as seen by a ship passing from the Pacific end to the Atlantic is as follows:
Thus, total length of the canal is 47.9 miles (77.1 kilometres).
Initially the locks at Gatun had been designed as 28.5 metres wide. In 1908 the United States Navy requested that the locks should be increased to have a width of at least 36 metres which would allow for the passage of US naval ships. Eventually a compromise was made and the locks were to be constructed to a width of 33 meters. Each lock is 300 metres long with the walls ranging in thickness from 15 metres at the base to 3 metres at the top. The central wall between the parallel locks at Gatun has a thickness of 18 metres and stands in excess of 24 metres in height. The lock gates are made from steel and measure an average of 2 metres thick, 19.5 metres in length and stand 20 metres in height. It is the size of the locks, specifically the Pedro Miguel Locks, along with the height of the Bridge of the Americas at Balboa, which limits the size of ships that may use the canal and determines the Panamax.
(links to map & photo sources)
|Bas Obispo Reach|
|Las Cascadas Reach|
|Pedro Miguel Locks|
Tolls for the canal are decided by the Panama Canal Authority and are based on vessel type, size, and the type of cargo carried.
For container ships, the toll is assessed per the ship's capacity expressed in twenty-foot equivalent units or TEUs. One TEU is the size of a container measuring by by 8.5 feet (6 m by 2.4 m by 2.6 m). Effective May 1, 2007, this toll is US$54 per TEU. A Panamax container ship may carry up to . A reduced toll is charged for container ships carrying no cargo or passengers.
Most other types of vessel pay a toll per PC/UMS net ton, in which one "ton" is actually a volume of 100 cubic feet (2.8 m³). (The calculation of tonnage for commercial vessels is quite complex.) As of 2007, this toll is US$3.26 per ton for the first 10,000 tons, US$3.19 per ton for the next 10,000 tons, and US$3.14 per ton thereafter. As with container ships, a reduced toll is charged for freight ships "in ballast".
Small vessels are assessed tolls based on their length. As of 2007, these are:
|Length of vessel||Toll|
|Up to 15.240 metres (50 ft)||US$500|
|More than 15.240 metres (50 ft) up to 24.384 metres (80 ft)||US$750|
|More than 24.384 metres (80 ft) up to 30.480 metres (100 ft)||US$1,000|
|More than 30.480 metres (100 ft)||US$1,500|
The most expensive regular toll for canal passage to date was charged on May 16, 2008 to the 964-foot (295 m) Disney Magic cruise liner, which paid just over US$331,200. The least expensive toll was 36 cents to American adventurer Richard Halliburton who swam the canal in 1928. The average toll is around US$54,000. The highest fee for priority passage charged through the Transit Slot Auction System was US$220,300, paid on August 24, 2006 by the Panamax tanker Erikoussa, bypassing a 90-ship queue waiting for the end of maintenance works on the Gatun locks, thus avoiding a 7-day delay. The normal fee would have been just US$13,430.
There were fears that efficiency and maintenance would suffer following the U.S. withdrawal; however, this does not appear to be the case, and the canal's efficiency appears to be improving under Panamanian control. Canal Waters Time (CWT), the average time it takes a vessel to navigate the canal, including waiting time, is a key measure of efficiency; according to the ACP, CWT is decreasing.
The Panama Canal Authority claims that the waterway's rate of accidents is at a record low.
Increasing volumes of imports from Asia which previously landed on the U.S. west coast ports are now passing through the canal to the American east coast. The total number of vessel transits in fiscal year 1999 was 14,336; this fell to a low of 13,154 in 2003, due at least in part to global economic factors, but has risen to 14,194 in 2006 (the canal's fiscal year runs from October to September). However, this has been coupled with a steady rise in average ship size and in the numbers of Panamax vessels passing, so that the total tonnage carried has risen steadily from 227.9 million PC/UMS tons in fiscal year 1999 to 296.0 million tons in 2006. Given the negative impact of vessel size on the rate of transits (for example, the inability of large vessels to cross in the Gaillard Cut), this represents significant overall growth in canal capacity, despite the reduction in total transits. The canal set a traffic record on March 13, 2006, when 1,070,023 PC/UMS tons transited the waterway, beating the previous record of 1,005,551 PC/UMS tons set on March 16, 2004.
The canal administration has invested nearly US$1 billion in widening and modernising the canal, with the aim of increasing capacity by 20%. The canal authority cites a number of major improvements, including the widening and straightening of the Gaillard Cut to reduce restrictions on crossing vessels, the deepening of the navigational channel in Gatun Lake to reduce draft restrictions and improve water supply, and the deepening of the Atlantic and Pacific entrances of the canal. This is supported by new vessels, such as a new drill barge and suction dredger, and an increase of the tug boat fleet by 20%. In addition, improvements have been made to the operating machinery of the canal, including an increased and improved tug locomotive fleet, the replacement of more than 16 kilometres of locomotive track, and new lock machinery controls. Improvements have been made to the traffic management system to allow more efficient control over ships in the canal.
The withdrawal of the U.S. has allowed Panama to sell excess electricity produced by the canal's dams, which was previously prohibited by the U.S. government. Only 25% of the hydroelectric power produced in the canal system is required to run the canal
Despite the gains which have been made in efficiency, the canal is soon expected to approach its maximum capacity. An additional complication is that the proportion of large (close to Panamax-sized) ships transiting the canal is increasing steadily; this may result in a further reduction in the number of transits, even if cargo tonnage rises. In any case, if the canal is to continue to serve the needs of world shipping, action will be required to increase its capacity.
Critics have also voiced their concerns over the planned increase in canal tolls, suggesting that the Suez Canal may become a viable alternative for cargo en route from Asia to the U.S. east coast. Nevertheless, demand for the Panama Canal continues to rise.
The increasing rate of melting of ice in the Arctic Ocean has led to speculation that the Northwest Passage may become viable for commercial shipping at some point in the future. This route would save 9,300 kilometres (5,800 mi) on the route from Asia to Europe compared with the Panama Canal, possibly leading to a diversion of some traffic to that route. However, such a route would still hold significant problems due to ice, as well as unresolved territorial issues.
Another interesting fact is that the mean sea level on either side of the canal is different. The Pacific side sea level is about 20cm higher than that of the Atlantic side due to differences in ocean conditions (e.g. water densities) and weather conditions.
An enlargement scheme similar to the 1939 Third Lock Scheme, to allow for a greater number of transits and the ability to handle larger ships, has been under consideration for some time. This enlargement scheme had been approved by the government of Panama. This proposal to expand the Canal was approved on a national referendum by approximately 80% on October 22, 2006.
The current plan is for two new flights of locks to be built parallel to and operated in addition to the old locks: one to the east of the existing Gatún locks, and one south west of Miraflores locks, each supported by approach channels. Each flight will ascend from ocean level direct to the Gatún Lake level; the existing two-stage ascent at Miraflores / Pedro Miguel will not be replicated. The new lock chambers will feature sliding gates, doubled for safety, and will be 427 metres (1,400 ft) long, 55 metres (180 ft) wide, and 18.3 metres (60 ft) deep; this will allow for the transit of vessels with a beam of up to 49 metres (160 ft), an overall length of up to 366 metres (1,200 ft) and a draft of up to 15 metres (50 ft), equivalent to a container ship carrying around 12,000 20-foot (6.1 m) long containers (TEU).
The new locks will be supported by new approach channels, including a 6.2 kilometre (3.8 mi) channel at Miraflores from the locks to the Gaillard Cut, skirting around Miraflores Lake. Each of these channels will be 218 metres (715 ft) wide, which will require post-Panamax vessels to navigate the channels in one direction at a time. The Gaillard Cut and the channel through Gatún Lake will be widened to no less than 280 metres (918 ft) on the straight portions and no less than 366 metres (1,200 ft) on the bends. The maximum level of Gatún Lake will be raised from reference height 26.7 metres (87.5 ft) to 27.1 metres (89 ft).
Each flight of locks will be accompanied by nine water reutilisation basins (three per lock chamber), each basin being approximately 70 metres (230 ft) wide, 430 metres (1410 ft) long and 5.50 metres (18 ft) deep. These gravity-fed basins will allow 60% of the water used in each transit to be reused; the new locks will consequently use 7% less water per transit than each of the existing lock lanes. The deepening of Gatún Lake, and the raising of its maximum water level, will also provide significant extra water storage capacity. These measures are intended to allow the expanded canal to operate without the construction of new reservoirs.
The estimated cost of the project is US$5.25 billion. The project is designed to allow for an anticipated growth in traffic from 280 million PC/UMS tons in 2005 to nearly 510 million PC/UMS tons in 2025; the expanded canal will have a maximum sustainable capacity of approximately 600 million PC/UMS tons per year. Tolls will continue to be calculated based on vessel tonnage, and will not depend on the locks used.
The new locks are expected to open for traffic in 2015. The present locks, which will be 100 years old by that time, will then have greater access for maintenance, and are projected to continue operating indefinitely. An article in the February 2007 issue of Popular Mechanics magazine describes the plans for the canal, focusing on the engineering aspects of the expansion project.
On September 3, 2007, work commenced on the expansion of the canal, with thousands of Panamanians at Paraiso, Panama City, witnessing a huge explosion bite into a hill. However the event was marred by the death of a worker, killed when his truck hit an electricity pylon. The first phase of the project will be dry excavations of the 218 meter (715 ft) wide trench connecting the Culebra Cut with the Pacific coast, removing 47 million cubic meters of earth and rock. The tendering process for the $3 billion project to build a new set of locks will begin later this year.