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Background of the Panama Canal

Fact sheet from the Panama Canal Company, 1996

Posted in: Panama, Rainforest Connection Live


As early as 8000 B.C., the Isthmus of Panama was used as a transit route by prehistoric man migrating through Central America to settle in South America. It wasn’t until 1502, on his fourth voyage of exploration, that Christopher Columbus, sailing under the Spanish flag, arrived on the Isthmus.

Spain began settlement of the Isthmus in 1510, and in 1534, Charles V ordered the first survey for a proposed canal across the 50-mile-wide Isthmus. A canal was beyond their capabilities, but the Spanish did pave mule trails with cobblestones to carry tons of gold moving back to Spain from the conquest of Peru. Vestiges of the Las Cruces trail can still be seen today.

In 1850, U.S. interests began construction of the Panama Railroad, just in time to make a fortune carrying gold-seekers on their way to California. They came to the Isthmus by boat, crossed the Isthmus, and continued on by boat.

In 1880, Ferdinand de Lesseps, fresh from his triumph building the Suez Canal, sold stock to millions of Frenchmen to finance the building of a canal in Panama. But the considerable skill of the French engineers was not enough to overcome the disease and geography they found on the Isthmus or make up for the mismanagement in France that brought the enterprise to financial ruin before the end of the century.

In 1903, following Panama’s declaration of independence from Columbia, Panama and the United States entered into a treaty by which the United States undertook to construct an inter-oceanic ship canal across the Isthmus. The following year the United States purchased the rights and equipment of the French Canal Interoceanique for $40 million and took over construction.

It took ten years, the labor of more than 75,000 men and women, and almost $400 million to complete the job. The builders of the Canal faced unprecedented problems: tropical disease; the unusual geology of the Isthmus that made landslides a constant hazard; the enormous size of the locks and volume of the excavation needed; and the need to establish whole new communities, to import every last nail, and to organize work on a scale never before seen.

Most of the names of the men and women who worked on the Canal are forgotten today, but their legacy lives on. Of those most well remembered, Colonel William Crawford Gorgas and his medical team are credited with eradicating yellow fever from the Isthmus and bringing malaria under control. Early Chief Engineer John F. Stevens and other railroad men set up the towns and the supply system and organized the all-important train system to haul dirt out of Culebra Cut, and Col. George Washington Goethals and his staff deserve credit for the final engineering designs and for pushing through the construction of the locks and Gatun Dam and excavation of the Cut.

The Canal opened to traffic on August 15, 1914; since that time, there have been more than 700,000 transits through the waterway. An aggressive program of maintenance has kept the Canal in top operating condition, and although the basic design remains as good as ever, the channel has been straightened, widened, and deepened, and improvements over the years have speeded operations and cut overhaul time at the locks. Over the past ten years, approximately $100 million per year has been spent in streamlining and improving Canal facilities and operations.

Since 1979, the Canal has operated under the terms of a treaty between the United States and the Republic of Panama signed in 1977, providing for the disestablishment of the Canal Zone, the growing participation of Panamanians at all levels of the Canal organization, and the turnover of the operation of the Canal to Panama on December 31, 1999.

Under the treaty, the Canal is operated by a United States Government agency, the Panama Canal Commission. The Commission is headed by an administrator and a deputy administrator and will operate through 1999 under the supervision of a bi-national Board of Directors comprised of five United States citizens and four Panamanian citizens. As provided in the treaty, the post of administrator was held until December 31, 1989, by a United States citizen, and the post of deputy administrator by a Panamanian citizen. After that period, the situation reversed, and for the remaining ten years of the treaty the administrator post is held by a Panamanian and a United States citizen serves as the deputy administrator.

Long-range plans and programs for a variety of Canal maintenance and improvement projects are being constantly developed and updated. These include deepening, widening, or straightening selected portions of the channel; replacing worn out or outdated equipment with new and improved designs; scheduling regular overhauls for Canal Locks and equipment, and maintaining a program of continual dredging throughout the waterway. These measures are meant to ensure that the Panama Canal will continue to be an economically viable route for world shipping for many decades.


The Panama Canal is 50 miles long from deep water in the Atlantic to deep water in the Pacific. It was cut through one of the narrowest and lowest saddles of the long, mountainous Isthmus that joins the North and South American continents. The original elevation was 312 feet above sea level where it crosses the Continental Divide in the rugged mountain range.

The Canal runs from northwest to southeast with the Atlantic entrance being 33.5 miles north and 27 miles west of the Pacific entrance. The air distance between the entrances is 43 miles.

It requires about 8 to 10 hours for an average ship to transit the Canal. During this brief time, the passengers aboard have an opportunity to see one of the modern wonders in operation.

The Canal’s principal physical features are Gatun Lake, and the central man-made lake stretching nearly all the way across the Isthmus; Gaillard Cut, the eight-mile-long excavation through the Continental Divide that extends Gatun Lake to Pedro Miguel Locks; the locks on both sides of the Isthmus that raise ships between sea level and the lake (Gatun Locks on the Atlantic and Pedro Miguel and Miraflores Locks on the Pacific); and the ports of Balboa on the Pacific and Cristobal on the Atlantic. At the time the Canal was built, Gatun Dam was the largest earth dam that had ever been constructed, and Gatun Lake was the largest man-made lake in the world. The three sets of locks were the most massive concrete structures ever built.

A ship that transits the Canal from the Atlantic to the Pacific enters the channel from Limon Bay at the Cristobal breakwater.

This sea-level section of the Canal channel on the Atlantic side is 6.5 miles long and 500 feet wide and runs through a mangrove swamp that is only a few feet above sea level in most places.

A ship is Raised or lowered 85 feet in a continuous flight of three steps at Gatun Locks. Each lock chamber is 110 feet wide and 1,000 feet long. The length of Gatun Locks, including the two approach walls, is 1.2 miles.

Gatun Lake & Dam

Gatun Lake through which ships travel for 23.5 miles from Gatun Locks to the north end of Gaillard Cut, covers an area of 163.38 square miles and was formed by the construction of Gatun Dam across the Chagres River adjacent to Gatun Locks. The two wings of the dam and the spillway have an aggregate length of about 1.5 miles. The dam is nearly a half mile wide at the base, tapering to a width of 100 feet at the crest, which is 105 feet above sea level, or 20 feet above the normal level of Gatun Lake.

Gaillard Cut

Because of its historical background perhaps no part of the Canal trip is more interesting to the ship passenger than Gaillard Cut. During the Canal construction period it was called Culebra Cut, but was renamed for Col. David DuBose Gaillard, the engineer who was in charge of this section of the Canal work.

This portion of the channel is 8.5 miles long and was carved through rock and shale for most of the distance. It was here that the principal excavation was required and here that devastating slides occurred during construction and soon after the Canal was opened.

Coming from the Atlantic, the ship enters the Cut where the Chagres River flows into the Canal channel at Gamboa. In the Cut, the ship passes Gold Hill on the left, the highest promontory along the channel. It rises 662 feet above sea level.

Contractor’s Hill, seen on the west bank opposite Gold Hill, originally had an altitude of 410 feet, but this was reduced to 370 feet to stabilize the hill in 1954. The channel in Gaillard Cut was originally excavated to a width of 300 feet. During the 1930s and 1940s, the straight section immediately north of Gold Hill was widened to 500 feet to provide a passing section for large ships, and during the period 1957-1971, the remaining portions of the Cut were also widened to 500 feet. Another long-term program to further widen and straighten Gaillard Cut, begun in January of 1992, is designed to improve vessel scheduling and safety and to increase Canal transit capacity.

The Pacific-bound ship enters Pedro Miguel Locks at the south end of Gaillard Cut. Here it is lowered 31 feet in one step to Miraflores Lake, a small artificial body of water a mile wide that separates the two sets of Pacific locks. The length of Pedro Miguel Locks is .83 miles.

The transiting ship is lowered the remaining two steps to sea level at Miraflores Locks, which is slightly over a mile in length. The lock gates at Miraflores are the tallest of any in the system because of the extreme tidal variation of the Pacific Ocean.

Other Facts

The SS Ancon made the first official ocean-to ocean transit through the Canal on August 15, 1914. In fiscal year 1994 there were 14,029 transits, of which 12,478 were made by ocean-going vessels of 300 or more Panama Canal net tons. During the year transiting ships carried nearly 170.8 million long tons of cargo and paid $419.2 million in tolls. The pre-World War II traffic peak was 7,479 vessel transits in 1939.

The longest ship to transit was the San Juan Prospector, now Marcona Prospector, an ore-bulk-oil carrier that is 973 feet long and has a beam of 106 feet. The widest ships to transit are the U.S.S. New Jersey and its sister ships, which have beams of 108 feet. Measuring 804.13 feet long, 05 feet wide and 63,957 Panama Canal net tons, the Crown Princess is the largest passenger ship to transit the Canal. Previous passenger vessel record-holders have been the Regal Princess (October 9, 1992), the Star Princess (October 5, 1990), the Queen Elizabeth 2 (March 25, 1975), and the Bremen (February 15, 1939).

The record for cargo carried through the Canal is held by the tanker Arco Texas, which transited on December 15, 1981, with 65,299 long tons of oil.

The highest Canal toll, as of this writing, is $141,344.97, paid by the Crown Princess on May 2, 1993. The lowest toll is 36 cents, paid by Richard Halliburton for swimming the Canal in 1928. Implementation of the Panama Canal Universal Measurement System (PC/UMS) began on October 1, 1994. The system is compatible with the new worldwide standard of tonnage measurement prescribed by the 1969 International Convention on Tonnage Measurement of Ships. Tolls were last increased effective October 1, 1992, to $2.21 a ton for laden ships and $1.76 for ships in ballast. The average toll for ocean-going commercial vessels during fiscal year 1994 was $33,785.

The fastest transit was that of the U.S. Navy hydrofoil Pegasus, which passed from Miraflores through Gatun Locks in two hours and 41 minutes in June 1979. The average time for a ship in Canal waters (including time spent at anchorage awaiting transit) is approximately 24 hours. The average time spent in transit from port to port is approximately 8 to 10 hours.

Gatun Dam was the largest earthen dam in the world until the construction of the Fort Peck Dam. Until Lake Mead was formed by the construction of Hoover Dam, Gatun Lake was the largest artificial body of water in the world.