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Kra Canal (Thailand) Excavation By Nuclear-powered Dredges

Richard Brook Cathcart
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Partial excavation of a Kra Canal in Thailand by nuclear-powered cutter-head suction dredges is examined. Such automated digging by a floating machine is deemed economically and geologically feasible. International and intra-national commerce will benefit greatly as well as the residents of peninsular Thailand. The 26 December 2004 tsunamis (particularly at Ko Phuket on the Andaman Sea coast) indicate more offshore and seaboard geological investigations must be carried out to ensure safe operation of the Kra Canal. Dredge spoils, if selectively sorted, have an unknown economic value in terms of heavy mineral mining potential. After the construction of the Kra Canal, the nuclear-powered dredges may find permanent useful work in the Malacca Strait, Sunda Strait and in the Gulf of Thailand or be used elsewhere.

1. Introduction

From 1405 until 1433, sailing ships – the largest of which displaced >2,500 tonnes – commanded by Admiral Zheng He departed from the Ming Empire's city of Nanjing in China and made port calls to exotic places as far away as Mombassa on Africa's east coast (Viviano, 2005). All seven trading voyages during that period sailed through the Strait of Malacca and usually stopped at Banda Aceh on Sumatra's west coast and then proceeded to Galle on Sri Lanka's west coast. The main goal of all seven fleet voyages was India's Malabar Coast, where rich China-India trading activities produced great personal wealth for the participants. Subsidiary commercial voyages from or to Galle occasionally passed through Adam's Bridge (Ravilious, 2004) and Palk Bay, where India has started dredging the Sethusamudram Shipping Canal, a long-planned macroproject, during June 2005 (Ramesh, 2005).

On 26 December 2004, the town of Banda Aceh located near the epicenter of the offshore ~9.3 Richter scale seismic moment magnitude Sumatra-Andaman earthquake was devastated by tsunamis (Wilson, 2005). The tsunamis generated in the Indian Ocean by that undersea seismic event killed many persons and damaged coast-sited infrastructure as far away as eastern Africa. (The largest aftershock so far, an 8.7 event occurring on 28 March 2005, did not cause damaging tsunamis.) Sri Lanka's Galle was badly affected and the tsunamis that entered Palk Bay – from the south and from the north – caused chaotic sea surface conditions that now call into serious question the wisdom of digging the channel for India's Sethusamudram Shipping Canal! The Sethusamudram Shipping Canal is not actually a land-cut "canal"; it is a dredged seafloor channel, probably first suggested by Alfred Dundas Taylor (1825-1898) sometime during the 1860s. Thailand's proposed shipping canal macro-engineering excavation effort, the Kra Canal Project to supplement the maritime chokepoint at the Strait of Malacca, will have to accommodate all new scientific data on the threats posed by future Sumatra-Andaman earthquakes.

Indeed, 21st century ocean shipping through the region extending from Thailand to the north coast of Australia must be prepared for future immense natural disasters that will directly and indirectly affect ship traffic negotiating the region by various passages: the shallow Sunda Strait may again experience a colossal volcanic eruption and consequent tsunamis at Krakatoa (Choi, 2003) and Japan is predicted to endure an economically crippling Tokyo earthquake (Mogi, 2004). Japan and China are the two main destinations of Middle East-loaded oil and LNG tankers to coastal Asia so a devastating earthquake in Tokyo could greatly impact the economics of the world oil market. Korycansky (2005) suggests that a Kra Canal Project won't be compromised by either the prospect or the occurrence of any future Sumatra-Andaman earthquakes owing to the W. G. Van Dorn Effect, whereby temblor-generated Indian Ocean tsunamis may break far offshore due to shoaling, reducing the deadly impact on Thailand's western shoreline, river mouths, seaports as well as at the several proposed entrances to the Kra Canal.

2. Kra Canal Macroproject History

Sometime during the early 21st century, the Isthmus of Kra may become the site for a new inter-oceanic canal macroproject which makes the circumnavigation of a peninsula unnecessary, saving shipping time for tanker vessels bound for China and Japan from the Middle East's oil and natural gas fields. If a final-version sea level Kra Canal is blueprinted, then a canal summit level will be absent and leakage from the canal will be minimal in a wet Isthmus of Kra flatland region with a prevailing high groundwater table. (The Cross-Florida Barge Canal, contemplated and excavated in the US from 1942 until its de-authorization in 1990, slightly resembles the proposed Kra Canal both in length and its effect geographically on transportation. The Cross-Florida Barge Canal was not a sea level channel and it was planned to be limited to barge traffic only. From 27 May through 2 June 2007, the World Dredging Congress [WODCON XVIII] will meet in Orlando, Florida)

Thailand's narrow, north-south running isthmus has been considered the likely site of a canal by shippers and macroengineers for more than a century. Non-native mapmakers first attempted inland exploration in 1839; the first printed planimetric map was sponsored and issued by the Royal Asiatic Society in 1879. The first iron-hulled, propeller-driven ship in the world, the SS Great Britain, was launched in 1843; vessels propelled in this manner can be scheduled and navigated virtually without consideration for natural wind and ocean currents. By 1863, British macroengineers A. Fraser and J. G. Furlong proposed a trans-isthmus barge canal utilizing the Pakchan River from its Indian Ocean mouth 42 km upriver to Kra (elevation ~34 m ASL) and then loading the barges onto a ship-railway for the remaining 80 km trip to the relatively shallow Gulf of Thailand, according to Charles Hadfield (1909-1996) (1986). The only ship-railway ever built during the 19th century, the Chignecto Marine Transport Railway, was located in Nova Scotia, Canada (Ircha, 1992).

The modern version of the Kra Canal will preferably be a twin-channel sea level facility, ~100 km long, ~100 m channel prism width featuring sloping sides stabilized at the local material's best angle of repose, ~25 m deep and will afford many types of vessels (oil and chemical tankers, bulk cargo carriers, refrigerated cargo ships, livestock carriers, LNG carriers, car carriers, container ships, dry cargo vessels, heavy lift vessels, tugs, RO-RO vessels) a direct route that bypasses the constricted – at its narrowest only ~3 km wide – and congested shipping lanes of the Strait of Malacca, saving ship owners several days of voyaging and associated operating expenses. A twin-channel Kra Canal would prevent head-on ship collisions and all traversing roads and rail tracks would not require extraordinarily long cross-Kra Canal bridge spans, including vertical lift bridges. (Short supplementary and complementary tunnels beneath the Kra Canal are feasible since off-worksite prefabricated concrete tubes can be floated to the work site, sunk and covered with material just like the subway constructed in Rotterdam, The Netherlands, that was opened for service in 1968.) Ships using the Kra Canal will have to adjust their operation to fit the tidal seawater movements in the two 100 m-wide one-way-only dedicated ship traffic channels, which probably will be ~1.0 to 1.75 m/s one way for a half day and then the same speed in the opposite direction for half a day. By comparison, a steady seawater maximum inflow into the Andaman Sea through the Strait of Malacca of ~1 m/s persists all year, altered only by temporary meteorological events such as the seasonal monsoons. Since ships must adjust their operations to the tides, it might seem just a single 200 m-wide channel would suffice, wherein convoys of ships would move in one direction for 12 hours, then move in the other direction for an equal period. Even Europe's heavily traveled (mostly by single barges or short barge trains) Rhine River has few head-on vessel collisions. However, the size of the seagoing ships and the volatile and pollution potential of their cargoes intended to use the Kra Canal is so much greater that it would pay in the long run economically to forestall any possible shipping disasters and simultaneous, widespread local contamination events, especially as intensive industrial and residential development is planned for the waterway's banks, which can be protected from erosion by ship waves, return currents and tidal fluxes by geotextile tubes filled with soil! The world's widest sea-level canal is the Cape Cod Canal. It is 162 m wide, 112 km long with a depth of 9.5 m and a tidal cycle that repeats every 6 hours, flowing first in one direction, then the other. Owing to some gentle curves, ships of >247 m length cannot safely use the Cape Cod Canal. From 1908 until 1940, when the waterway reached its final form, ~42,000,000 m3 of material was dredged, shifted from one place to another, obliterating immobile life forms where the spoil was removed and where it finally came to rest. Its banks are armored with riprap to prevent regular tidal currents and frequent ship-generated waves from eroding the sides of the man-made maritime passage.

To form the proposed Kra Canal's twin 100 m-wide navigation channels, a minimum of 820,000,000 m3 of soil and broken rock must be removed and re-deposited. (A slightly greater volume of materials is alleged, by some landscape historians, to have created The Netherlands by planned shifting of ~1,000,000,000 m3 of materials, initiating vast human control of both the landscape and the seascape.) Four funnel-less and partly automated nuclear-powered cutting-head suction dredges, working 24 hr/day per year for approximately 5 years could shift all the material excavated and piled to create the finished Kra Canal. Four nuclear-powered dredges, two commencing work on the east coast and two starting on the west coast of Thailand could complete the work before AD 2020, if the nuclear reactors that power them are working (post-prototype) machines by AD 2015. Refueled and serviced in dry-dock, the four dredges will have long post-Kra Canal working histories elsewhere in Thailand and at the other two vital-to-world-trade maritime straits around Indonesia. To avoid the necessity of a summit level lock system or an elaborate ship-railway – that is, to insure the Kra Canal functions as a fully sea-level waterway – some standard industrial mining explosives blasting must break the few intervening hard rock barriers. It is unknown yet whether the dredge spoil material, if properly sorted mechanically, chemically or magnetically, will have any economic value – it could contain tin and other valuable minerals – encouraging industrial separation from the bulk material mass moved out of shear necessity to create the Kra Canal. The waste material may find special uses in reshaping the landscape next to the completed Kra Canal, where adjacent drainage basin integrity will inevitably be permanently altered; additionally, there will be new possibilities at both terminals of the Kra Canal related to a linkage of onshore and offshore macroprojects, such as is evident (by the Kansai International Airport opened in 1994) in Japan's Osaka Bay.

The major hazard to all shipping traffic will be found in the Indian Ocean where vessels entering or leaving the Strait of Malacca will intersect the sea-lane for ships leaving or entering the Kra Canal; side impact ship collisions will be the greatest risk to mariners using the Kra Canal and the Strait of Malacca! Currently, piracy and the threat of terrorism plagues shippers using the choke-point sea route passing Singapore at slow speeds owing to the narrowness and shallowness (~25 m) of the Strait of Malacca and the crowdedness of the several dedicated sea lanes traveled by ~50,000 to 100,000 ships yearly. The risk of damaging tsunamis in the Strait of Malacca may be remarkably greater than at the western entrance of the proposed Kra Canal. A terrorist attack on ships that could close both (separated) channels of a Kra Canal seems about as unlikely as a total physical closure of the Strait of Malacca. It is worthwhile noting that the wartime shutdowns (1956-1957 and 1967-1975) of the sea level Suez Canal, which was dug through sand and soft rock ~15 m ASL and opened to commerce in 1869, and now has a depth of ~19 m, induced oil and natural gas producers and shippers to rely on fast supertankers that simply took other suitable routes. In other words, macro-engineers simply designed ports, and other onshore and offshore facilities that facilitated the building and servicing of enormous ships, making it economically worthwhile to travel a longer-distance detour route. Total closure of the narrowest section of the Strait of Malacca between Sumatra and Singapore could force all vessel types to use diversions that are nearly 1,000 km further! However, a supplementary/complementary Kra Canal single 100 m-wide channel temporary closure may not suffer that economic decline since passing smaller ships using the parallel channel could still serve the many seaports on the coastlines of mainland Asia and Japan, negating the need for costly gigantic offshore big tanker anchorages and marine oil and LNG unloading facilities. Furthermore, Singapore's freshwater imports can be augmented with seagoing plastic pods – sometimes termed "dracone barges" – safely using a markedly less-crowded sea-lane serving metropolitan Singapore (Cathcart, 2005).

If the proposed Kra Canal is ever to become a physical reality during the 21st century, the Government of Thailand will have to finally approve the macroproject's justification literature related to its building based on reliable feasibility studies covering the amount and type of traffic that could be accepted and passed safely, kinds of commodities that would be transported on the waterway, the effect on the regional and national landscape and subsequent economic development of Thailand along with the anticipated carefully estimated cost of all necessary excavation, construction, maintenance and operation. The 26 December 2004 tsunamis, which even retarded piratical attacks afterwards, is alleged to have caused the postponement or outright cancellation during 2005 of Thailand's proposed $7.3 billion (2005 USA dollar) "Land Bridge" consisting of seaboard ports on the Andaman Sea and the Gulf of Thailand and cross-Kra peninsula oil and natural gas pipelines, superhighways, high-speed railways and other infrastructure. That earthquake as well as the tsunamis it generated also highlights the very real need for constant re-mapping of the continental shelf seafloor and the coastline since many obvious-to-observer geographical changes have occurred! There may be many entirely unknown new hazards to ship navigation that await accidental discovery by big vessels transiting the region!

3. The Nuclear-Powered Dredge

At the 1970 World Dredging Conference of the World Dredging Association (founded 1967), William R. Murden (1915-1997) and Robert E. Donovan (1942-1996) proffered the first floating nuclear-powered cutter-head suction dredge proposal. Thirty-five years before the US Supreme Court held in a 22 February 2005 ruling on Stewart v Dutra Construction Company (No. 03-814) that a tugboat-moved dredge is a "vessel" under the Longshore and Harbor Workers Act, Murden and Donovan designed a sleek self-propelled prototype vessel capable of plying the ocean and excavating a sea level canal route through Columbia south of the water-locked, continually dredged Panama Canal (opened 1914). With the escalation during 2005 AD of the world price for bunker oil burned by ships, and the regional and global ecological necessity to not befoul the air with polluting gases and aerosols from the cheapest grades of oil, nuclear-powered ships should be reconsidered by 21st century industrial infrastructure developers. A small, sealed, tamper-resistant, portable, autonomous nuclear reactor container, producing up to 100 MW may become available to shipbuilders during the early 21st century – that is, before 2020 AD.

One example of a technically possible source of nuclear power generated electricity for electric turbine-propelled big dredges is the NEREUS Project (Naturally Safe, Efficient, Reactor, Easy to operate, Ultimately simple and Small). "Nereus" is Greek mythology's God of Shipping. Another example of a suitable device is the SSTAR (Small, Sealed, Transportable, Autonomous Reactor) being developed by the US Department of Energy in collaboration with Lawrence Livermore National Laboratory (Rennie, 2004). SSTAR, in its 100 MW incarnation, will weigh 500 tonnes and be 15 m high by 3 m wide in the shape of cylinder with domed ends and an estimated volume of ~438 m3. It will be a thoroughly tested R&D prototype by circa AD 2015. Both modern reactor designs are ship-suitable in that they have the necessary safe power output, small volume and low weight characteristics. Thailand is eligible under provisions of the Non-Proliferation Treaty enacted in 1970 to obtain access to peaceful nuclear technology. Operational monitoring of NEREUS and SSTAR can be done remotely.

The Kra Canal Project will require approximately 4 nuclear-powered dredges, each dredge costing (in 2005 US dollars) about $100,000,000. The planned estimated total cost of the Kra Canal is $25,000,000,000. So the cost of 4 globally mobile nuclear-powered suction dredges – which can be recycled after ~5 years of near-autonomous operation and securely moved great distances in traveling casks conveyed by ships and trucks – amounts to merely 1.6% of the Kra Canal macroproject's total construction cost, about equal to all pre-excavation geo-technical investigation cost. One or two of these powerful dredges may be retained for maintenance operations while one or two may be moved elsewhere on the planet. We think one logical application would be to dredge and maintain deep approach channels in the Gulf of Thailand, which has a mean depth of ~45 m and a maximum depth of ~80 m; on Thailand's 740 km-long Andaman Sea shoreline the depth of the water on the continental shelf as far as 3 km from the beach is often only ~3 m. Continuous dredging of the Strait of Malacca and the Sunda Strait will also be potentially profitable future business options.

4. Nuclear-Powered Dredge Specifications

Our dredge design concept is based on a seagoing, self-propelled, hydraulic cutter-head dredge capable of sailing under its own power to Thailand. An SSTAR or a NEREUS-powered dredge will have efficient and aesthetically attractive ship form lines. Its greatest advantage over all existing barge-like floating dredges is due to the absence of large onboard oil bunkers and freshwater tanks. Heavy minerals (columbite, magnetite, ilmenite, rutile, zircon) – identified and sorted during post-excavation spoils distribution – can then be pumped via flexible pipelines or floating conveyor-belts from or to bank-side portable extraction machines (with appropriate holding bins), making it unnecessary to have any onboard bulk material storage accommodation. Each vessel will be equipped with 4 retractable cutter-head dredge pumps that can be enclosed by streamlined bow doors as on extant car ferries. Each NEREUS or SSTAR power plant installation should produce at least 50,000 SHP (~37 MW) for each self-propelled seagoing dredge – about the equivalent of a modern-day cruise liner. The remaining ~63 MW of power will then be available to operate all other equipment.

5. Summary

The literature of modern oceanography generally exposes the ever-increasing impacts of humanity on the Earth's ocean. The geologic foundation and sediment dynamics of the sea-bottom define the basic environment for living biotic communities of bottom-dwelling organisms, which are influenced by seawater circulations that also affect organisms living in the water column. Earth-crust events, such as the 26 December 2004 earthquake and following tsunamis, can rapidly alter the environment drastically and strongly affect all humans living on epicenter-adjacent seaboards. Thailand's Kra Canal Project proposal needs a thorough reexamination subsequent to this catastrophic early-21st century seismic event and also requires us to consider the use of nuclear-powered cutter-head suction dredges to stabilize and improve the entire region surrounding it. 21st century macroengineers are becoming increasingly influenced by a prevailing new historical viewpoint regarding the past, current meaning and future importance to humanity of Earth's ocean. Dredge tailings have almost the same properties as the silica particles found in a child's outdoor play-box; dredge spoils leave open to the Kra Canal macroproject planners' imagination, moods and desires just what things can or will be constructed eventually by piling and shaping of such particulate materials (Beatty, 1966).

6. References

Beatty, R. A., 1966. The inert becomes ‘ert'. Landscape Architecture, January, 125-128.
Cathcart, R. B., 2005. Nautical jugs or not? Current Science, 88, 1211-1212.
Choi, B. H., 2003. Simulation of the trans-oceanic tsunami propagation due to the 1883 Krakatau volcanic eruption. Natural Hazards and Earth System Sciences, 3, 321-332.
Hadfield, C., 1986. World Canals: Inland Navigation Past and Present. New York: Facts on File. 186.
Ircha, M. C., 1992. The Chignecto ship railway: a 19th century engineering innovation, Canadian Journal of Civil Engineering, 19, 164-177.
Korycansky, D. G, 2005. Offshore breaking of impact tsunami: The Van Dorn effect revisited. Geophysical Research Letters, 32, L10608.
Mogi,, K., 2004. Two grave issues concerning the expected Tokai Earthquake. Earth Planets Space, 56, li-lxvi.
Murden, W. R. and Donocan, R. E., 1971. A Nuclear Powered Dredge for the 70s. In Anon., 1970 Proceeding of WODCON World Dredging Conference. Canoga Park, California: Xyzyx Information Corporation, 163-208.
NEREUS website.
Ramesh, R., 2005. Sethusamudram Shipping Canal Project. Current Science, 88, 536-537.
Ravilious, K., 2004. The new stone age. New Scientist, 184, 38-41.
Rennie, G., 2004. Nuclear Energy to Go: A Self-Contained, Portable Reactor. Science & Technology Review, July-August, 20-22.
Viviano, F., 2005. China's Great Armada. National Geographic. 208, 28-53.
Wilson, M., 2005. Modeling the Sumatra-Andaman Earthquake Reveals a Complex, Nonuniform Rupture. Physics Today, 58, 19-21.