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Greetings from Panama! My name is Marina Ehrman and I have been a professional tour guide and promoter for Panama Tourism and Travel Company since 2005. I love what I do and am proud to share what my country has to offer. It is filled with endless leisure and commercial attractions, friendly happy people who open their doors to all visitors. Panama is a country of incomparable natural beauty with a variety of tourist attractions, beautiful beaches in the Pacific and Caribbean. The tropical climate year round with its diversified flora, fauna and indigenous groups make it one of the most important of Ecotourism in Latin America. I invite you to know our country’s history, culture and also enjoy the cuisine, folklore and traditions that only a place in the world can provide………Panama! Contact me and I’ll organize your visit and will be happy to welcome you in Panama. For more information on Panama, follow my Facebook page and my blog. Visit www.panamatourismtravel.com
Showing posts with label Panama Canal Locks. Show all posts
Showing posts with label Panama Canal Locks. Show all posts

See The Panama Canal at Miraflores Locks



Tour Avaliable
Panama Canal Partial Transit
Panama Canal Full Transit
Panama Canal Tour

For those wishing to see that “8th Wonder of the World”, but have little time, I suggest this tour. This two hour tour takes you to the Miraflores Locks where we will visit the Miraflores Visitor Center and see the great ships of the world transiting through.

Miraflores is the name of one of the three locks that form part of the Panama Canal and the name of the small lake that separates these locks from the Pedro Miguel locks upstream. In the Miraflores locks, vessels are lifted (or lowered) in three stages totalling 8 m, allowing them to transit to or from the Pacific Ocean port of Balboa (near Panama City). Ships cross below the Puente de las Américas (Bridge of the Americas) which connects North and South America.

Four exhibition halls constitute the heart of the Miraflores Visitor Center . The exhibitions include historic pieces, interactive modules, video presentations, models of the Panama Canal, and objects used in Canal operations.




  • The History Hall portrays the background, technological innovations, and sanitary initiatives that went hand in hand with the construction of the Canal. This exhibition hall honors the hundreds of men and women who made this achievement possible.



  • The Hall of Water: Source of Life emphasizes the importance of water, conservation of the environment and biodiversity, protection of the Canal Watershed, and the ACP’s commitment to the sustainable management of this resource and the interoceanic region.



  • The Canal in Action depicts in an amusing manner how the Canal operates and allows us the experience of being inside a navigation simulator and one of the lock culverts. A virtual ocean-to-ocean transit is also made possible through the use of a topographical model. This exhibition showcases Canal improvement, modernization, and maintenance projects.



  • The Canal in the World provides information on the importance of the Canal to world trade; describes the trade routes it serves; and identifies its main users, the various types of vessels that transit the waterway, and the commodities they carry. In addition, it presents an overview of studies conducted in order to guarantee the future competitiveness of the Canal and the benefits to the Republic of Panama.
  • The Expansion of the Panama Canal



    The Expansion of the Panama Canal (Third Set of Locks Project)  is a project that will double the capacity of the Panama Canal by 2014 by allowing more and larger ships to transit. Then-Panamanian President Martín Torrijos presented the plan on April 24, 2006 and Panamanian citizens approved it in a national referendum by 76.8% of the vote on October 22, 2006.

    The project creates a new lane of traffic along the Canal by constructing a new set of locks. Details of the project include the following integrated components:
    • Construction of two lock complexes—one on the Atlantic side and another on the Pacific side—each with three chambers, which include three water-saving basins;
    • Excavation of new access channels to the new locks and the widening of existing navigational channels; and,
    • Deepening of the navigation channels and the elevation of Gatun Lake's maximum operating level.
    On September 3, 2007, after approval by the Cabinet, National Assembly and referendum, the Panama Canal expansion project officially started. Panama's then-president Martín Torrijos stated that the Canal will generate enough wealth to transform Panama into a First World country. The project is also expected to reduce poverty by about 30%, resulting in an 8% poverty rate in Panama afterwards.
    Background

    The capacity of the Panama Canal is determined by a number of factors, of which the most important is the size of the locks that raise and lower ships as they pass through the canal. The smallest dimensions of the locks are 110 ft (33.53 m) wide, 1,050 ft (320.04 m) long, and 85 ft (25.91 m) deep. Because of clearance issues, the usable sizes are somewhat smaller (for example, the maximum usable length of each lock chamber is about 1,000 ft (304.8 m). The maximum size of the ships that can transit the canal is known as the Panamax.

    Since the 1930s, all of the Canal widening studies have determined that the most effective and efficient alternative to enhance Canal capacity is the construction of a third set of locks, with bigger dimensions than those of the locks built in 1914. In 1939, the United States initiated the construction of locks designed to allow the transit of commercial and war ships, whose dimensions exceeded the size of the existing locks. In 1942, after advancing the excavations significantly, the Americans suspended the third set of locks project because of the outbreak of World War II. In the 1980s, the tripartite commission formed by Panama, Japan, and the United States took up the issue again, and like the Americans in 1939, determined that a third set of locks with larger lock chambers was the most appropriate alternative for increasing Canal capacity. Today, the studies developed by the Panama Canal Authority (ACP) as part of its Master Plan, with a horizon to the year 2025, confirm that a third set of locks, larger than those existing now, is the most suitable, profitable and environmentally responsible way to increase Canal capacity and allow the Panamanian maritime route to continue to grow.

    Throughout its history, the Canal has continually transformed its structure and adjusted to trade requirements and international maritime transport technologies. In this manner, the Canal has managed to increase its competitiveness in a sustainable manner.

    Then-President Torrijos in his speech on April 24, 2006, announcing the project, said that "…to say it in a graphic manner, [the Canal] is like our 'petroleum'. Just like the petroleum that hasn't been extracted is worthless, and that in order to extract it you have to invest in infrastructure; the Canal requires to expand its capacity to absorb the growing demand of cargo, and generate more wealth for Panamanians".

    Cargo volume

    On the basis of ACP's projections, during the next 20 years, cargo volume transiting the Canal will grow at an average of three percent per year, doubling 2005's tonnage by the year 2025. As such, providing the Canal with the capacity to transit larger vessels will make it more efficient by allowing the transit of higher cargo volumes with relatively fewer transits and less water use.

    Historically, the dry and liquid bulk segments have generated most of the Canal's revenues. Bulk cargo includes dry goods, such as grains (corn, soy and wheat, among others), minerals, fertilizers, coal, and liquid goods, such as chemical products, propane gas, crude oil and oil derivatives. Recently, the containerized cargo segment has replaced the dry bulk segment as the Canal's main income generator, moving it to second place. On the other hand, the vehicle carriers segment has become the third income generator, replacing the liquid bulk segment. Shipping industry analysis conducted by the ACP and top industry experts indicate that it would be beneficial to both the Canal and its users to expand the Canal because of the demand that will be served by allowing the transit of more tonnage.

    The question is, however, whether the trend upon which the Panama Canal Authority makes those projections can continue for a generation.

    The growth in Panama Canal usage over the past few years has been almost entirely driven by increased U.S. imports from China passing through the canal en route to ports on the U.S. East and Gulf Coasts. But it is increasingly recognized in both the United States and China that this imbalance in trade is unsustainable and will be reduced in some sort of adjustment in the coming years, though it is important to note that any such imbalance need not be made up by physically shipped goods, but could be made by other trade such as intellectual property as China upgrades its intellectual property protection laws. The ACP, however, presumes that it will not only not be adjusted, but will continue to grow for a generation as it has for the past several years. One of the central points of the canal expansion proposal's critics, most prominently made by former canal administrator Fernando Manfredo, is that it's unrealistic to attempt to predict canal usage trends over a generation, most improbable to expect that U.S. imports from China will continue to grow as they have the past few years over a generation, and irresponsible to bet Panama's financial future on such a projection.

    Competition

    The most direct competition to the Canal is from alternative routes which present options for the transport of cargo between the same geographical points of origin and destination.

    The opening of the Northwest Passage to commercial traffic could pose an alternative to the Canal in the long term. It is thought that global warming is likely to open the passage for increasing periods of time, making it attractive as a major shipping route. However the passage through the Arctic Ocean would require significant investment in escort vessels and staging ports. Therefore the Canadian commercial marine transport industry does not anticipate that this route will be a viable alternative to the Panama Canal within the next 10 to 20 years.

    The two main current competitors of the Panama Canal are the U.S. intermodal system and the Suez Canal. The main ports and merchandise distribution centers in these routes are investing in capacity, location, and maritime and land infrastructure to serve Post-Panamax container ships and handle their cargo volumes. According to the ACP, the growing trend to use such ships in transcontinental routes competing with the canal is irreversible. If so, by the year 2011, approximately 37% of the capacity of the world's container ship fleet will consist of vessels that do not fit through the current canal, and a great part of this fleet could be placed in routes that compete with Panama.

    The proposal states that strengthening its competitive position will allow the canal to accommodate demand and serve its customers. If the canal were to have the capacity to serve the growing demand, Panama could be transformed into the most important connectivity hub in the continent by joining together at the isthmus the north–south continental routes with the east-west transcontinental routes. Accordingly, the canal will continue to be viable and competitive in all of its routes and segments, and contribute significantly to Panama's development and growth while maintaining its position as one of the main world trade routes.

    Predictions

    According to the ACP, the canal will reach its maximum sustainable capacity between the years 2009 and 2012. When it reaches this capacity it will not be able to continue to handle demand growth, resulting in a reduction in the competitiveness of the Panama maritime route

    As approved by the Panamanian people, construction for the expansion project is slated to conclude by 2014. All creative means will be employed by the ACP to stretch capacity until the construction is done.
    The proposed expansion of the canal by the construction of a third set of locks will allow it to capture the entire demand projected through 2025 and beyond. Together, the existing and new locks will approximately double the capacity of the present Canal.

    Critics such as former legislator Dr. Keith Holder, co-author of the legislation that created the ACP, point out that canal usage is seasonal and that even during the few months when it is most crowded the bottleneck that slows traffic is not the locks but the narrow Culebra Cut, in which there is a limited capacity for large ships to pass one another.

    Although the Canal is reaching its maximum capacity, the ACP clarifies that this does not mean that ships will be unable to transit the Canal. However, it does mean that the Canal's growth capacity will stagnate and that it will not capture additional cargo volumes.

    The former head of the Panama Canal's Dredging Division, Thomas Drohan, who is a critic of the expansion plan, discounts allegations that this is a problem in the short term—he argues that if the supply of any good or service becomes short, any business can raise its price for it and this would apply to Panama Canal tolls as much as it does to petroleum.

    The project

    Locks


    The Canal today has two lanes each with its own set of locks. The proposal consists of adding a third lane through the construction of lock complexes at each end of the Canal. One lock complex will be located on the Pacific side to the southwest of the existing Miraflores Locks. The other complex will be located to the east of the existing Gatun Locks. Each of these new lock complexes will have three consecutive chambers designed to move vessels from sea level to the level of Gatun Lake and back down again. Each chamber will have three lateral water-saving basins, for a total of nine basins per lock and 18 basins total. Just like the existing locks, the new locks and their basins will be filled and emptied by gravity, without the use of pumps. The location of the new locks uses a significant portion of the area excavated by the United States in 1939 and suspended in 1942 because of the start of World War II. The new locks will be connected to the existing channel system through new navigational channels.
    The new lock chambers will be 1,400 ft (426.72 m) long, by 180 ft (54.86 m) wide, and 60 ft (18.29 m) deep. They will use rolling gates instead of miter gates, which are used by the existing locks. Rolling gates are used in almost all existing locks with dimensions similar to those being proposed, and are a well-proven technology. The new locks will use tugboats to position the vessels instead of locomotives. As in the case of the rolling gates, tugs are successfully and widely utilized for these purposes in locks of similar dimensions.

    Navigational channels

    According to the plan, a 3.2 km (2.0 mi)-long access channel will be excavated to connect the new Atlantic locks with the existing sea entrance of the Canal. To connect the new Pacific-side locks with the existing channels, two new access channels will be built:
    • The north access channel, which will connect the new Pacific-side lock with the Gaillard Cut, circumventing Miraflores Lake, and which will be 6.2 km (3.9 mi) long; and,
    • The south access channel, which will connect the new lock with the existing sea entrance on the Pacific Ocean, and which will be 1.8 km (1.1 mi) long (see figure 5). The new channels will be at least 218 meters (715 ft) wide, both on the Atlantic and Pacific sides, which will permit Post-Panamax vessels to navigate in these channels in a single direction at any time.

    Gatun Lake raised 1.5 feet (0.46 m)

    All Canal elevations are referred to Precise Level Datum (PLD), which is close to Atlantic and Pacific entrance mean sea level. The maximum operational level of Gatun Lake will be raised by approximately 0.45 meters (1.5 ft) — from the present PLD level of 26.7 meters (87.5 ft) to a PLD level of 27.1 meters (89 ft). Combined with the widening and deepening of the navigational channels, this component will increase Gatun Lake's usable water reserve capacity and will allow the Canal's water system to supply a daily average of 165,000,000 US gal (625,000,000 L; 137,000,000 imp gal) of additional water. This additional water volume is enough to provide an annual average of approximately 1,100 additional lockages without affecting the water supply for human use, which is also provided from Gatun and Alhajuela Lakes.

    Construction timeline

    The construction of the third set of locks project is slated to take between seven to eight years. The new locks could begin operations between fiscal years 2014 and 2015, roughly one hundred years after the canal first opened.

    Finances

    The main purpose of the Canal expansion program is to increase Panama's ability to benefit from the growing traffic demand. This growing demand is manifested both in increased cargo volume and vessel size that will use the Panama route. In this sense, the Canal, with a third set of locks, will be able to manage the traffic demand forecast beyond 2025, and total revenues for that year, adjusted for inflation, will amount to over USD $6.2 billion.

    Estimated cost

    The cost to construct the third set of locks is estimated by the ACP at approximately US $15 to 25 billion. This estimate includes design, administrative, construction, testing, environmental mitigation, and commissioning costs. Additionally, this cost includes contingencies to cover risks and unforeseen events, such as those that might be caused by accidents, design changes, price increases, and possible delays, among others. The most relevant program cost is that of constructing the two new lock complexes – one on the Atlantic side and the other on the Pacific side – with estimated costs of approximately US $1.110 billion and US $1.03 billion each, plus a US $590 million provision for possible contingencies during their construction.

    Opponents contend the project is based on uncertain projections about maritime trade and the world economy. Prof. R.N. Mendez, an economist who works for the University of Panama, alleged that the economic and financial projections are based on manipulated data. Independent engineers, most notably Humberto Reynolds and Tomas Drohan Ruiz, the former head of Engineering and Dredging of the Panama Canal, say that the project will cost much more than currently budgeted and that it is too risky for Panama.
    M.A. Bernal, professor at the University of Panama, thinks that confidence in the budget of the Panama Canal Authority is undermined because of engineering and consultancy firm Parsons Brinckerhoff's involvement. Parsons Brinckerhoff is best known for the Big Dig in Boston, which ended up costing three times the estimated amount with several structural and safety concerns.

    Estimated profit

    According to the ACP, the third set of locks is financially profitable, producing a 12% internal rate of return. The third set of locks project is self-financed and its financing will be separate from the Government's financing. The state will not guarantee or endorse any loans undertaken by the ACP for the project's execution. With tolls increasing at an annual average rate of 3.5% for 20 years, and according to the most probable traffic demand forecast and construction schedule, the external financing required will be mainly temporary and on the order of USD $2.3 billion to cover peak construction activities between 2009 and 2011. With the cash flows generated by the expanded Canal, investment costs will be recovered in less than 10 years and financing could be repaid in approximately eight years.
    What "self-financing" actually means, however, is disputed. At least half of the money needed for the canal expansion project will have to be borrowed, and the ACP does not calculate the interest on that as part of the project's costs.
    The ACP's revenue projections are based on suppositions about increase in canal usage and the willingness of shippers to pay higher tolls instead of seeking competing routes, both of which critics question.

    Environmental Impact


    The ACP claims in the proposal that the third set of locks project is environmentally viable. It has been found that all possible adverse environmental impacts can be mitigated through existing procedures and technology, and no immitigable or permanent adverse impacts on the population or the environment are anticipated. There are no elements within the scope of the project that will compromise its environmental viability, such as communities, primary forests, national parks or forest reserves, relevant patrimonial or archaeological sites, agricultural or industrial production areas, or tourist or port areas. The project will not cause permanent or irreversible impacts on water or air quality. The proposed water supply program fulfills the objectives of maximizing the water capacity of Gatun and Alhajuela Lakes, and applies the most efficient water utilization technology at the locks so no new reservoirs will be required. Consequently, it will not be necessary to relocate communities. The entire area directly affected by the project is located within ACP operational and administrative areas.

    Critics to the project contend there are a lot of environmental topics to be considered. For example: link between El Niño (ENSO) and global warming threat to water supplies. The ACP has commissioned a number of studies by a number of consultants about water supply and quality issues, and some like Eric Jackson (editor of the Panama News internet newspaper), Gonzalo Menendez(former head of the National Environmental Authority or ANAM by its Spanish initials), Ariel Rodriguez (University of Panama biologist), former Vice Minister of Public Works Grettel Villalaz de Allen and others are some of the most prominent critics of the canal expansion plan from the point of view of water quality issues. Jackson contends that ACP's public statements often do not match the findings of their studies. He says that the Delft Hydraulics, WPSI Inc, and DHI studies all say that no matter what is done to mitigate the problem, the water saving basins feature of the proposed new locks would increase the intrusion of salt water into Gatun Lake, from which about half of Panama's population takes its drinking water. The chosen method to partially mitigate this problem is to "flush" the new locks with fresh water from Gatun Lake — but that tends to defeat the proposed new locks’ water saving feature and raises questions about the security of the urban water supply.
    However, one of the leading environmental organizations in Panama, ANCON (National Association for Nature Conservation) says that the studies and projections of operation of the Third Lock, including the water saving basins, state in a credible manner that there will be very low levels of salinization of waters of Gatun Lake and that these levels would preserve the biologic separation of the oceans with the safekeeping of the biodiversity and water quality for human use.

    Employment generation

    According to the ACP, the Canal expansion's impact on employment will first be observed in the jobs directly generated by the economic boom experienced during the years of its construction. Approximately 35,000 to 40,000 new jobs will be created during the construction of the third set of locks, including 6,500 to 7,000 additional jobs that will be directly related to the project during the construction's peak years.
    However, officials state that the most important impact on employment will be medium and long term and will come from the economic growth brought about by extra income generated by the expanded Canal and the economic activities produced by the increase in Canal cargo and vessel transits – all of these contributing to fully leverage the advantages of Panama's geographic position.
    The labor required for construction of the third set of locks will, in its vast majority, be done by Panamanians. To ensure the availability of Panamanian labor necessary for the third set of locks project and its connected activities, the ACP and public and private authorities will work jointly to train the required workforce with sufficient lead time, so that it has the necessary competencies, capabilities and certifications. The amounts necessary to carry out these training programs are included in the cost estimates of the project.

    Critics dismiss this as pure demagogy, noting that by the ACP's own studies at the peak of construction there will be fewer than 6,000 jobs created and that some of these will be highly skilled posts filled by foreigners because there are no Panamanians who are qualified to fill them.
    Among those who oppose the canal expansion proposal is Panama's construction workers' union, SUNTRACS. The union's secretary general, Genaro Lopez, argues that while some construction jobs would be created by the project, the debt that Panama incurs to build a third set of locks would not be defrayed by increased canal usage and thus an increased part of canal revenues would go toward paying the debt, reducing the waterway's contributions to the national government's general fund and in turn reducing money for road projects, public schools, police protection and all other government services.
    Critics also claim the project lacks an accompanying social development plan. Then-President Torrijos has since accepted the request to develop one with the mediation of the United Nations Development Programme.

    Voices supporting the project

    ANCON (National Association for Nature Conservation) has given its approval of the environmental studies of the proposal and stated some recommendations if the project is approved. The following have also endorsed the proposal:

    Voices against the project

    Former President Jorge Illueca, former sub-administrator of the Panama Canal Commission, Fernando Manfredo, shipping consultant Julio Manduley and industrial entrepreneur George Richa M. say that the expansion is not necessary; they claim that the construction of a mega-port on the Pacific side would by itself be sufficient to meet probable future demand. The logic behind this is that said port would be the second port (the first being Los Angeles) deep enough in the American Pacific capable of handling post-panamax ships. As Panama is already a natural trading route, it would be able to handle the movement of containers from the Pacific to the Atlantic side via railroad, where containers would be reloaded to other ships for worldwide distribution. In addition, the following organizations and people oppose the project:
    • The Council on Hemispheric Affairs (COHA) stated in a press release that under the Torrijos government, the expanding Panama Canal will not likely serve the needs of the vast majority of Panamanians. Much of the benefits will be tied to the commercial interests of the country's accountants, bankers and lawyers, as well as their U.S. counterparts, and world trade. They also say that the administration's rampant corruption and other flaws raise questions about Panama's capacity to supervise such an enormous project. COHA has received some letters which point out factual errors and plans to modify its statement to reflect this.
    • Former President Guillermo Endara and his Vanguardia Moral de la Patria Party,MOLIRENA, a conservative, business oriented party that normally gets about 10 percent of the vote.
    • Most of the Panamanian left and most of the labor movement, including for example CONUSI(National Independent Syndicate Union) and FRENADESO (National Front for the Defence of Social and Economic Rights).
    • Most members of the nationalistic Panameñista Party (Grettel Villalaz de Allen and Gonzalo Menendez, mentioned above, and former legislator Gloria Young are prominent examples).
    • Some environmentalist leaders and groups: Biodiversidad Panama, whose principal leader is University of Panama biologist Ariel Rodriguez, and former National Environmental Authority director Gonzalo Menendez.
    • Proponents of Liberation Theology, in part because they suspect that poor farmers among whom they have a social base would be adversely affected. The canal expansion issue has aggravated the breach between this mainly Catholic strain and the Catholic hierarchy. This group has chosen the radical Catholic priest Father Conrado Sanjuras as its principal spokesperson for relations with the Electoral Tribunal.

    Panama Canal Locks

    The Panama Canal Locks, which lift ships up 25.9 m (85 ft) to the main elevation of the Panama Canal, were one of the greatest engineering works ever to be undertaken at the time, eclipsed only by other parts of the canal project. No other concrete construction of comparable size was undertaken until the Hoover Dam in the 1930s. The total length of the lock structures, including the approach walls, is over 3 kilometres (nearly two miles).
    The locks, which have a total of six steps, limit the maximum size of ships which can transit the canal, known as Panamax. Each of these steps has two lock chambers, doubling the amount of traffic that can be handled; together they raise ships from sea level to a height of 25.9 m (85 ft).
    The locks are to be expanded in the near future to allow more and larger ships to use the canal.

    Design
    There are three sets of locks in the canal. A two-step flight at Miraflores, and a single flight at Pedro Miguel, lift ships from the Pacific up to Lake Gatun; then a triple flight at Gatun lowers them to the Atlantic side. All three sets of locks are paired; that is, there are two parallel flights of locks at each of the three lock sites. This, in principle, allows ships to pass in opposite directions simultaneously; however, large ships cannot cross safely at speed in the Gaillard Cut, so in practice ships pass in one direction for a time, then in the other, using both "lanes" of the locks in one direction at a time.
    The lock chambers are 33.53 meters (110 ft) wide by 320.0 meters (1050 ft) long, with a usable length of 304.8 metres (1000 ft). These dimensions determine the maximum size of ships which can use the canal; this size is known as Panamax. The total lift (the amount by which a ship is raised or lowered) in the three steps of the Gatun locks is 25.9 m (85 ft); the lift of the two-step Miraflores locks is 16.5 m (54 ft). The single-step Pedro Miguel lock has a lift of 9.5 m (31 ft). The lift at Miraflores actually varies due to the extreme tides on the Pacific side, between 13.1 m (43 ft) at extreme high tide and 19.7 m (64.5 ft) at extreme low tide; the tides on the Atlantic side, however, are very small.
    The lock chambers are massive concrete structures. The side walls are from 13.7 to 15.2 metres (45 to 55 feet) thick at the bases; towards the top, where less strength is required, they taper down in steps to 2.4 m (8 ft). The centre wall between the chambers is 18.3 m (60 ft) thick, and houses three long galleries which run the full length of the centre wall. The lowest of these is a drainage tunnel; above this is a gallery for electrical cabling; and towards the top is a passageway which allows operators to gain access to the lock machinery.

    Filling and draining
    Each lock chamber requires 101,000 m3 (26,700,000 US gal; 22,200,000 imp gal) to fill it from the lowered position to raised; the same amount of water must be drained from the chamber to lower it again. Embedded in the side and centre walls are three large water culverts, which are used to carry water from the lake into the chambers to raise them, and from each chamber down to the next, or to the sea, to lower them. These culverts start at a diameter of 22 ft (6.71 m), and reduce 18 ft (5.49 m) in diameter — large enough to accommodate a train. Cross culverts branch off from these main culverts, and run underneath the lock chambers to openings in the floors. There are fourteen cross culverts in each chamber, each with five openings; seven cross culverts from the sidewall main culverts alternate with seven from the centre wall culvert.
    The water is moved by gravity, and is controlled by huge valves in the culverts; each cross culvert is independently controlled. A lock chamber can be filled in as little as eight minutes; there is significant turbulence in the lock chamber during this process

    The gates
    The gates which separate the chambers in each flight of locks must hold back a considerable weight of water, and must be both reliable and strong enough to withstand accidents, as the failure of a gate could unleash a catastrophic flood of water downstream.
    These gates are of enormous size, ranging from 47 to 82 ft (14.33 to 24.99 m) high, depending on position, and are 7 ft (2.13 m) thick; the tallest gates are required at Miraflores, due to the large tidal range there. The heaviest leaves weigh 662 t (730 short tons; 652 long tons); the hinges themselves each weigh 16.7 t (36,817 lb). Each gate has two leaves, 65 ft (19.81 m) wide, which close to a V shape with the point upstream; this arrangement has the effect that the force of water from the higher side pushes the ends of the gates together firmly. The gates can only be opened when, in the operating cycle, water level on both sides is equal.
    The original gate machinery consisted of a huge drive wheel, powered by an electric motor, to which was attached a connecting rod, which in turn attached to the middle of the gate. These mechanisms were replaced with hydraulic struts beginning in January 1998, after 84 years of service. The gates are hollow and buoyant, much like the hull of a ship, and are so well balanced that two 19 kW (25 hp) motors are enough to move each gate leaf; if one motor fails, the other can still operate the gate at reduced speed.
    Each chamber also contains a pair of auxiliary gates which can be used to divide the chamber in two; this is designed to allow for the transit of smaller vessels — such as canal tugs — without using the full quantity of water. They were originally incorporated because the overwhelming majority of all ships of the early 1900s were less than 600 ft (183 m) in length, and would therefore not need the full length of the lock chamber. Nowadays these gates are rarely used; instead, small boats such as tour boats, tugs, and yachts are passed in groups

    Safety features
    A failure of the lock gates — for example, caused by a runaway ship hitting a gate — could unleash a flood on the lands downstream of the locks, as the lake above the locks (Gatun Lake or Miraflores Lake) drains through the lock system. Extra safety against this is provided by doubling the gates at both ends of the upper chamber in each flight of locks; hence, there are four gates in each flight of locks which would have to fail to allow the higher level of water to pass downstream. The additional gates are 21 m (70 ft) away from the operating gates.
    Originally, the locks also featured chain barriers, which were stretched across the lock chambers to prevent a ship from running out of control and ramming a gate, and which were lowered into the lock floor to allow the ship to pass. These fender chains featured elaborate braking mechanisms to allow a ship up to 10,000 tons to be safely stopped; however, given the precise control of ships made possible by the mules, it was very unlikely that these chains would ever be required. With many modern canal users being over 60,000 tons, and given the expense of maintaining them, the fender chains were reduced in number in 1976 and finally removed in 1980.
    Beyond this, the original design of the locks had yet another safety feature — emergency dams which could be swung across the locks at the upper end of every flight. These consisted of swinging bridges, from which girders were lowered to the lock floor; steel shutters could then be run down these girders to block the flow of water. Monthly drills were held, by night and day, to make sure that these dams could be deployed in an emergency.
    In the late 1930s, the original dams were replaced by new dams, which were raised out of slots in the bottom of the lock chambers, either hydraulically or by compressed air. The new dams were themselves retired in the late 1980s, and today, no emergency dams are in place

    Controls
    Since all the equipment of the locks is operated electrically, the whole process of locking a ship up or down can be controlled from a central control room, which is located on the centre wall of the upper flight of locks. The controls were designed from the outset to minimise the chances of operator error, and include a complete model of the locks, with moving components which mirror the states of the real lock gates and valves. In this way, the operator can see exactly what state the locks and water valves are in.
    Mechanical interlocks are built into the controls to make sure that no component can be moved while another is in an incorrect state; for example, opening the drain and fill valves of a lock chamber simultaneously

    Construction

    The project of building the locks began with the first concrete laid at Gatun, on August 24, 1909, by Philadelphia based company Day & Zimmermann (formerly known as Dodge & Day).
    The locks at Gatun are built into a cutting made in a hill bordering the lake, which required the excavation of 3,800,000 m³ (5,000,000 cubic yards) of material, mostly rock. The locks themselves were made of 1,564,400 m³ (2,046,100 cubic yards) of concrete.
    The quantity of material needed to construct the locks required extensive measures to be put in place to handle the stone and cement. Stone was brought from Portobelo to the Gatun locks; the work on the Pacific side used stone quarried from Ancon Hill.
    Huge overhead cableways were constructed to transport concrete into the construction at Gatun. 26 metre (85 ft) high towers were built on the banks of the canal, and cables of 6 cm (2.5 inch) steel wire were strung between them to span the locks. Buckets running on these cables carried up to six tons of concrete at a time into the locks. Electric railways were constructed to take stone, sand and cement from the docks to the concrete mixing machines, from where another electric railway carried two 6-ton buckets at a time to the cableways. The smaller constructions at Pedro Miguel and Miraflores used cranes and steam locomotives in a similar manner.
    Concrete is normally moulded in formwork, temporary structures which give shape to the concrete as it sets. For a simple construction, these would normally be made quite simply of wood, but the scale of the locks demanded extraordinary forms.
    The forms for the walls consisted of towers, fronted with braced vertical sheets, 19 cm (7½ inches) thick, mounted on rails to allow the locks to be constructed in sections; a section of lock would be poured behind the form, and when it was set, the form would be moved to do the next section. Each of the twelve towers was 23.8 m (78 ft) high by 11.0 m (36 ft) wide. The forms for the culverts were made of steel, and were collapsible so they could be removed and moved along after each section of culvert had set. There were, in all, 33 forms for the centre and side-wall culverts, each 3.7 m (12 ft) long; and 100 smaller forms for the lateral culverts.
    The Pacific-side locks were finished first; the single flight at Pedro Miguel in 1911 and Miraflores in May, 1913.
    The seagoing tug Gatun, an Atlantic entrance working tug used for hauling barges, had the honor on September 26, 1913, of making the first trial lockage of Gatun Locks. The lockage went perfectly, although all valves were controlled manually since the central control board was still not ready.