Building the World

September 22, 2022
by Building The World
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TRANSPORT: Tunnels – Environmental Option

“Hamburg-Mitte-Elbe Tunnel” by Anita Janda, 2019. CC4.0 wikimedia. Included with appreciation.

Ten years to plan, nine years to build, seven billion to budget: the Fehmarnbelt Fixed Link Tunnel will offer an alternative to a 45-minute ferry between Germany’s Fehmarn island and Denmark’s Lolland isle. The new tunnel will clock travel time to ten minutes by car and seven minutes by train. Not just a faster trip between islands, Fehmarnbelt will reduce passage duration between Copenhagen and Hamburg.

Fehmarnbelt Fixed Link Tunnel will shorten the travel time between Copenhagen and Hamburg. Image: “Fehmarn bridge” by Bowzer. CC by SA 3.0, wikimedia. Included with appreciation.

It will be the world’s longest immersed tunnel, although at 11.1 miles long (18 kilometers) shorter than the Channel Tunnel stretching 31 miles (50 kilometers). Other differences include construction methods. The Channel Tunnel was built using a traditional boring machine. Fehmarnbelt will be pre-fab: tunnel sections completed on land will be submerged and then connected. Each section is 711 feet long (217 meters) – about half the size of a large container ship. All that length is heavy – each section weighs as much as 13,000 elephants.

One section of the tunnel’s pre-fab building blocks weighs as much as 13 elephants. Image: “Elephant,” by Felix Andrew, 2005. Public domain gnu. Included with appreciation.

In a world where the environment is part of every decision, Fehmarnbelt Fixed Link will include newly established stone reefs on both Danish and German sides, similar in some ways to the natural paths fashioned along the New River of England. Tunnels offer other environmental advantages, bringing automobiles, trains, and trucks below the surface where emissions be captured, if the tunnels are so equipped.

SMART Tunnel in Kuala Lumpur, Malaysia, combines transport and flood control. Image: “SMART tunnel entrance,” by David Boey, 2018. Wikimedia CC4.0. Included with appreciation.

Another environmental advantage of tunnels is response to flash floods. The Stormwater Management and Road Tunnel (SMART) in Kuala Lumpur, Malaysia, is designed to divert rainwater into a lower section, allowing the upper section to remain open to vehicular traffic. Floodwater diversion, storage, and reuse options are certain to present problems (and opportunities) in our future: can tunnels be part of the solution?

Thanks to Cherie E. Potts for suggesting this post, and to Frank P. Davidson for proposing and achieving the success of the Channel Tunnel.

Fehmarnbelt Fixed Link. “Why we’re building the Fehmarnbelt fixed link.” Femern. https://femern.com

Prisco, Jacopo. “Denmark and Germany now building the world’s longest immersed tunnel.” September 2022, CNN.com. https://www.cnn.com/travel/article/fehmarnbelt-longest-immersed-tunnel-cmd/index.html

SMART. https://smarttunnel.com.my/smart/what-is-smart/

Building the World Blog by Kathleen Lusk Brooke and Zoe G. Quinn is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Un

August 26, 2022
by Building The World
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TRANSPORT: Tunnel Visionaries

Underwater tunnels like the Channel Tunnel, and Japan’s new tunnel under the Tsugaru Strait, are engineering feats. Here, “Underwater tunnel in Mandalay Bay Aquarium” photo by Daniel Ramirez, 2014. Creative Commons 2.0. Included with appreciation.

Walking on water takes a miracle, but walking through water requires excellent planning. When the Channel Tunnel was first designed, over a luncheon meeting in New York City hosted by Frank P. Davidson, Thomas Lamont, and representatives of Bechtel, Brown & Root, and Morrison Knudsen Company, a 1959 decision saved lives in 2022. The group engaged Charles Dunn of International Engineering Company of San Francisco, CA, to design the project. Dunn added a service tunnel. It was not mandatory, but it proved prescient.

Channel Tunnel has three tunnels – two rail lines and a service tunnel between. The design by Charles Dunn has saved lives. Image: “Cross section with service tunnel in between two rail lines,’ by Commander Keane and Arz. Wikimedia commons. Public domain. Included with appreciation.

The three tunnels under the Channel (in French, “La Manche”) are a north-running tunnel, a south-running tunnel, and – between them – a service tunnel. During an August 2022 incident, a train experienced an alarm warning, stopped, and held for assessment. Passengers walked for 15 minutes from the rail shuttle to a freight train that conveyed them through and out of the service tunnel. That freight train did not have the usual accommodation for passengers: no elegant meal service, not even seats. But with Dunn’s design, the service tunnel, and its freight train did provide safety. When passengers arrived in Folkestone, terminal restaurants welcomed them with free food and beverages.

Strait of Dover between England and France. Image: NASA, 2000. Public Domain. Included with appreciation.

The service tunnel in the Channel Tunnel has proven its worth before. In 1996, a fire broke out in the Channel Tunnel when a train carrying heavy goods vehicles (there are passenger trains as well as freight trains carrying trucks) sparked a fire. The train was brought to a controlled stop adjacent to an entrance to the service tunnel. While there were no reported fatalities, some people suffered from smoke inhalation. The fire was fought by English and French teams who extinguished the flames after considerable effort. Tunnel repair was carried out by Freyssinet, a French engineering firm. Bi-national Channel Tunnel Safety Authority (CTSA) chaired one of three inquiries: the result was regular bi-national team practice exercises and shared operational procedures. In 2008, a fire in the Chunnel, started by a truck that spread to other vehicles, caused damage but no fatalities or serious injuries. It is worth noting that when the Channel Tunnel project began, the service tunnel was the first built.

“Tsugaru Srait” by Kyoyaku, adapted by Bourrichon, 2019. Creative Commons 4.0. Included with appreciation.

How can the Channel Tunnel’s design inspire the future? Japan, home to many tunnels that connect the nation composed of four main islands – Hokkaido, Honshu, Kyushu, and Shikoku – is currently planning a new tunnel across the Tsugaru Strait for automobile traffic between Honshu and Hokkaido. The tunnel would span 31 kilometers (19. 26 miles) and cost about $7 billion (720 billion yen). In the new Tsugaru Strait tunnel, there will be two decks: the top for autonomous vehicles like self-driving cars; the lower for freight trains. Economic benefits include increased ability to transport agricultural produce from Hokkaido, estimated at 34 billion yen ($249 million).  The project will take 15 years to build; construction costs would be recouped in 32 years. Tolls are estimated to be 9,000 yen for cars ($65).

“Platooning” is a method for linking controls of lines and groups of autonomous vehicles. Could this be used in the new Tsugaru Strait Tunnel? Image: “Platooning Back” by U.S. Department of Transportation, 2019. Public Domain. Included with appreciation.

Tsugaru Strait is also the location of Japan’s Seikan Tunnel, serving only trains; it was not built with a separate escape or service tunnel, but with two emergency escape points in the system, Tappi-Kaitei station and Toshioka-Kaitei station. Shinkansen trains in Japan’s high speed rail network use the Seikan system. Fifty trains traverse the Seikan Tunnel every day, and night trains offer sleeping accommodation. Seikan suffered inundation accidents during construction but no fatalities.

“Cross-Harbour Tunnel Bridge Fire,” in Hong Kong, 2019. Photograph by Studio Incendo. Wikimedia. Included with appreciation.

Other tunnels around the world have experienced accidents, fires, and floods. In Hong Kong, the Cross-Harbour Tunnel was the first built there for underwater transit; in 2019, protestors set fire to tollbooths, causing the tunnel to close but avoiding any fatalities. In 1991, two trains collided in the Severn Tunnel joining England and Wales; 185 passengers were injured but none fatally. In 1999, a fire in the Mont Blanc Tunnel joining France, Italy, and Switzerland, caused 39 deaths and 14 non-fatal injuries. These examples point out the wisdom of Dunn’s design of an extra service tunnel for the Channel Tunnel.

“Shadertoy Tunnel Example,” by Inigo Quilez, 2016. Creative Commons, wikimedia. Included with appreciation.

In a time of budget cuts, along with an increased focus on transportation infrastructure, this week’s Channel Tunnel problem and its successful rescue solution may serve to underscore the importance of safety, and its support by budget and planning. In a new era when safety measures for autonomous vehicles and driverless cars are forefront, Japan’s new tunnel may set an important example for tunnel transport infrastructure for autonomous vehicles. What safety measures should be included?

Bove, Tristan. “Passengers forced to walk through ‘terrifying’ emergency tunnel under the sea after France-England train breaks down.” 24 August 2022. Fortune. https://fortune.com/2022/08/24/eurotunnl-evacuation-passengers-walk-terrifying-service-tunnel-between-france-england/

Davidson, Frank P. and K. Lusk Brooke. “The Channel Tunnel,” pages 761-804, Building the World (2006) ISBN: 0313333742.

Failure Knowledge Database. “Train Fie in Hokuriku Tunnel.” http://www.shippai.org/fkd/en/cfen/CA1000605.html

Rosenberg, Jennifer. “How the Channel Tunnel Was Built and Designed.” 12 August 2019. ThoughtCo. https://www.thoughtco.com/the-channel-tunnel-1779429

Takahashi, Toru. “$7bn plan for new Japan undersea tunnel warms up after years on ice: Project would allow auto traffic between Honshu and Hokkaido.” 3 January 2021. Nikkei Asia. https://asia.nikkei.com/Business/Engineering-Construction/7bn-plan-for-new-Japan-undersea-tunnel-warms-up-after-years-on-ice

Building the World Blog by Kathleen Lusk Brooke and Zoe G. Quinn is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Un

 

October 25, 2019
by Building The World
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TRANSPORT: frequent flier programs

“Red Arrows at the Royal Air Show” August 2011 Image: wikimedia. Will frequent flier programs change with the climate?

First, it was Greta Thunberg who traveled throughout Europe to speak to, among others, the French National Assembly; the teen climate activist, nominated for the Nobel Peace Prize, declared the transport decision as a preference for lower-emissions travel. A new word came into common parlance: Flygskam (Swedish) or “Flight Shame.”

Greta Thunberg who traveled by train in Europe and by sailboat to the United Nations in New York, USA, in 2019. Image: wikimedia

Next, Imperial College London and Richard Carmichael reported to the Committee on Climate Change (CCC), an independent advisory agency of the UK government, that the nation’s goal of carbon neutrality by 2050, to meet the Paris Agreement of COP21, must address air travel: “Flying is a uniquely high-impact activity and is the quickest and cheapest way for a consumer to increase their carbon footprint.”

As a result, frequent flier programs, both of airlines and of credit cards, might have to go. Citing data that just 15% of the UK population takes 70% of the flights, CCC report states: “Given the scope for frequent fliers to have carbon footprints many times that of the average UK household, a lack of policy in this area is likely to be increasingly seen as inconsistent and unjust and risks damaging engagement with climate action.” (Carmichael 2019)

In the United States, 12% of Americans fly more than six round-trips per year; mainly business travelers, these frequent fliers are responsible for two-thirds of air travel, and therefore participating in aviation emissions. That’s 3 tons of carbon dioxide per year, per flier. Some policy specialists differentiate between business and pleasure air travel. But 83% of Americans drive cars, and most heat or cool their homes – activities that also cause considerable carbon emissions.

Concerned about aviation’s future, some airlines are staying ahead of the trend: British Airways, Aer Lingus, and Iberia (art of IAG, International Airlines Group) announced a strategic sustainability plan to 1)replace older aircraft, 2)invest in sustainable jet fuel, and 3) develop new technologies that take carbon out of the atmosphere. (Guy, 2019) Businesses and universities are starting to allow longer travel time for staff who travel for work, so that they may avoid flying; train travel, including the Channel Tunnel, is recommended. Japan is updating Shinkansen (high speed rail originally built for the 1956 Olympics) in anticipation of the Tokyo 2020 Olympic Games.

Saying “bye” to frequent flier programs? Image: wikimedia

Do you have frequent flier miles? What is your opinion on how incentives in transport may change?

Carmichael, Richard. “Behavior change, public engagement, and Net Zero.” 10 October 2019. Committee on Climate Change, Centre for Energy Policy and Technology and Centre for Environmental Policy, Imperial College London. https://www.theccc.org.uk/publication/behaviour-change-public-engagement-and-net-zero-imperial-college-london/behaviour-change-public-engagement-and-net-zero-richard-carmichael/

Guy, Jack. “Ban air miles to combat climate crisis, recommends UK research.” 15 October 2019. CNN/Travel. https://www.cnn.com/travel/article/air-miles-ban-report-scli-intl/index.html.

International Airlines Group (IAG). “Sustainability.” https://www.iairgroup.com/en/sustainability

Tabuchi, Hiroko and Nadja Popovich. “How Guilty Should You Feel About Flying?” 17 October 2019, The New York Times. https://www.nytimes.com/interactive/2019/10/17/climate/flying-shame-emissions.html.

Thunberg, Greta. “Address to the National Assembly” July 23, 2019. France. https://www.youtube.com/watch?v=ESDpzwWrmGg

Building the World Blog by Kathleen Lusk Brooke and Zoe G. Quinn is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unporte

May 20, 2019
by Building The World
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TRANSPORT: Channel Tunnel Celebrates 25 Years

“Chris Froome: First person to cycle through Eurotunnel.” In the Chunnel’s third ‘service’ tunnel. Image: wikimedia.

Frank P. Davidson, American co-founder, in 1957, of the Channel Tunnel Study Group, coined the word “chunnel” for the fixed link between France and England that had been a dream of Napoleon, and drawn up as an engineering plan by Albert Mathieu-Flavier in 1802. Many historians credit Davidson whose Study Group worked with Charles Dunn of International Engineering Company/Morrison-Knudsen. Bechtel Corporation, Brown & Root, and banker Thomas Lamont, to design the three-tunnel system, as the “father of the Channel Tunnel.”

“Folkestone White Horse” carved by artist Charlie Newington as a Millennial Landmark on the cliffs overlooking the English Terminus of the Channel Tunnel.

Built by 13,000 workers from France and England, the tunnel opened 6 May 1994 and was immediately named one of the Seven Wonders of the Modern World. It’s an economic, and environmental, success. The Channel Tunnel has proved valuable to participating economies (2018 figures):

Total passengers: 20,611,337

Total cars: 2,610,242

Total freight trains: 1,797

Total trucks: 1,641,638

Total trade through the Channel Tunnel: Euro 137.8bn

Source: Ernst & Young 2018

ENVIRONMENT: Economic contribution is matched, perhaps exceeded, by environmental value: the tunnel helps to collect and mitigate emissions, making the Eurostar trip from London to Paris 90% cleaner than a short-haul air flight.

ANNIVERSARY GIFT: For its 20th anniversary, in 2014, Eurotunnel added another Channel to the Chunnel (the neologism was coined by Davidson): mobile telephone and internet came to the Channel Tunnel. What should the Channel Tunnel do for its 25th anniversary. One possibility: enhancing the power of connectivity, seeing borders as opportunities, not barriers.

Davidson, Frank P. MACRO (New York: William Morrow and Company, 1983). ISBN: 0688021824. Pages: 38-40; 94-102, 296-97.

Davidson, Frank P. editor. With photography by Lilian Kemp. Tunneling and Underground Transport: Future Developments in Technology, Economics, and Policy. (New York: Elsevier, 1985). ISBN: 0444011307

Ernst & Young LLP: Peter Arnold, Harriet Walker, Carmela Carrea. “Economic Footprint of the Channel Tunnel in the EU: An analysis of the value of trade traveling through the Channel Tunnel between the UK and EU countries.” June 2018. https://www.getlnkgroup.com/uploadedFiles/assets-uk/the-channel-tunnel/180604-EY-Channel-Tunnel-Footprint-Report.pdf/

Hunt, Donald. The Tunnel: The Story of the Channel Tunnel 1802-1994. (London: Images Publishing, 1994). ISBN: 1897817347.

Minihane, Joe. “How the Channel Tunnel changed Europe forever.” 4 May 2019, CNN.com. Includes video about how the world’s longest sea tunnel was built with 13,000 English and French workers. “A shared achievement that should stand the test of time.” https://www.cnn.com/travel/article/channel-tunnel-anniversary/index.html.

“New Channel in the Chunnel,” Lusk Brooke, 6 May 2014, Building the World Blog. https://blogs.umb.edu/buildingtheworld/2014/05/07/new-channel-in-the-chunnel/

Building the World Blog by Kathleen Lusk Brooke and Zoe G Quinn is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported Licen

May 12, 2017
by Building The World
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Mothers Walk for Peace

Image: Photographer, Rebecca Eschler, 2008. Wikimedia commons.

A higher purpose, above ground; a safer world, below. Why not send cars and trucks underground, where new roads for autonomous vehicles might be easier to build? Elon Musk, of Tesla and SpaceX fame, envisions cars positioned on platforms that descend to traverse networks below ground. A similar design was earlier suggested by David Gordon Wilson of MIT whose palleted highways would increase speed and decrease accidents. Tunnels have changed transport around the world: the Channel Tunnel and the Mount Blanc Tunnel are recent examples. Boston depressed the Central Artery, resulting in a Greenway atop with a special park called the Mothers’ Walk. Nearby, walk towards a better world with the Louis D. Brown Peace Institute for the Mother’s Day Walk for Peace. Will Elon Musk’s underground highways promote a cleaner, safer environment with more parks above where people can walk and nature flourish? It’s an exciting idea with a name that belies the innovation: The Boring Company.

For more: mothersdaywalk4peace.org

For Elon Musk, watch the YouTube video: https://www.youtube.com/watch?v=hpDHwfXbpfg

Building the World Blog by Kathleen Lusk Brooke and Zoe G Quinn is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

November 4, 2016
by Building The World
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Faster Than A Speeding Bullet Train

Chuo Shinkansen: Japanese “flying trains” will travel 1 mile every 10 seconds. Image: wikimedia commons.

What’s faster than a speeding bullet, a phrase used to describe Superman? The new Shinkansen, or Japanese bullet train. Japan Rail announced the design of a magnetic levitation train that will achieve speeds over 600 kilometers per hour (374 miles per hour), or 1 mile (1.5km) every 10 seconds. Maglev trains are already in regular service in China: Shanghai and Changsha; as well as Korea, in Incheon. When Japan hosted the 1964 Olympics, Shinkansen was introduced, with the Tokyo-Osaka line. By  2002, Shinkansen had transported 382 billion passengers, with a 99% on-time record. Japan’s success inspired France’s TGV and Germany’s Intercity-Express. Maglev Chuo Shinkansen will shoot from Tokyo to Nagoya in 40 minutes; the line will soon extend to Osaka. Japan will follow a new law passed in 2001 that decrees that developers need not purchase land above, if digging more than 40 meters (131 feet) below. The law names the underground territory as daishindo (extreme underground). When will Amtrak emulate Japan’s leadership in train transport?

Hongo, Jun. “Tokyo underground: taking property development to new depths.” Japan Times. 12 April 2014. http://www.japantimes.co.jp/life/2014/04/12/lifestyle/tokyo-underground/#.WBuoQygylDJ/

Lo, Andrea. “Can mega-fast maglev revive Japan’s rail reputation?” 3 November 2016. CNN. http://www.cnn.com/2016/10/31/asia/japan-record-breaking-maglev-train/

Building the World Blog by Kathleen Lusk Brooke and Zoe G Quinn is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

June 9, 2016
by Building The World
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Tunnel (En)Vision

World’s longest tunnel, Gotthard. Image: wikimedia commons.

The Gotthard Base Tunnel, world’s longest, opened to fanfare and diplomacy, and a ballet corps of 600, in June 2016. The Gotthard massif has long challenged transport efforts; Gotthard now joins the Mont Blanc Tunnel in traversing mountainous terrain. Boston’s Central Artery/Tunnel Project also features a tunnel to bring vehicular traffic underground while a new greenway park graces the urban landscape above. Tunnels are an ancient instinct: moles know the routes underground, while human endeavors appear to have been early home-improvement projects by cave dwellers adding a second room. Land tunnels preceded water transit ways such as the Channel Tunnel. But all tunnels have one aspect in common: emissions trapped in a contained environment. Research contrasting on-road carbonyl emission factors in two highway tunnels, Caldecott Tunnel near San Francisco, California and Tuscarora Mountain Tunnel in Pennsylvania, was conducted 2002. WSP|Parsons Brinckerhoff recommended jet fans to move fumes through long road tunnels. But could there be a better solution? Will the EPA‘s capture and sequestration research apply to tunnels? Might ExxonMobil and FuelCell Energy‘s innovation to cleanse carbon dioxide from the exhaust of natural gas- and coal-fired plants be applied to other situations? Carbon capture could take on a new meaning if tomorrow’s tunnels might become channels for environmental improvement.

Building the World Blog by Kathleen Lusk Brooke and Zoe G Quinn is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License

March 10, 2016
by Building The World
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Hyperloop Pod(cast)

Duke Ellington’s theme song: “Take the ‘A’ Train.” Image: wikimedia commons.

Duke Ellington once sent a note to Billy Strayhorn, giving directions to his New York apartment. As the Pennsylvania pianist rode the rails, another kind of note came to him, a song: “Take the ‘A’ Train.” Public transport, whether the A Train or the Hyperloop, is an opportunity to engage the traveler. For example, in Beijing, on subway Line 4, riders can scan a barcode on their mobile device, opening a cultural window. Each month, ten works of Chinese culture are offered, the collection rotating in connection with the China National Library. Opportunities for bystanders to become understanders could expand in Japan, originator of the QR code that combines four modes: numeric, alphanumeric, byte/binary, and kanji. Shinkansen, Japan’s fast train network, opened to success for the 1964 Tokyo Olympics. As Shinkansen improves and expands, will Japan use QR codes as cultural portals? Hyperloop is projected to zoom from Los Angeles to San Francisco in 35 minutes. At speeds reaching up to 760mph, (as contrasted with proposed high-speed rail taking 2.5 hours at a top speed of 200 mph) passengers will remain seated, perhaps especially ready for a Hyperloop podcast. Design of Hyperloop passenger pods recently opened to student competition.  MIT won the January 2016 round when Elon Musk invited top contenders to demonstrate their designs on the SpaceX California Test Track later in 2016. Included in the design of the passenger experience might be cultural transport with a nod, and a note, to Ellington and Strayhorn.

Ella Fitzgerald sings “Take the ‘A’ Train.”https://www.youtube.com/watch?v=BJ_4cRG8B1g

Nath, Trevor. “Hyperloop System Vs. High Speed Train: What’s Best for California?” 29 October 2015. http://www.investopedia.com/articles/investing/050815/elon-musks-hyperloop-economically-feasible.asp

Patel, Neel V. “After Winning the Hyperloop Competition, MIT Looks Ahead.” National Geographic/Inverse.com. 17 February 2016.

Hyperloop.mit.edu; @MITHyperloop.

Building the World Blog by Kathleen Lusk Brooke and Zoe G Quinn is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License

 

July 30, 2015
by Building The World
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Channels of Migration

Photo: Makisig, “Malinta Tunnel, Corrigedor, Philippines,” wikimedia commons.

Eurotunnel estimates that 37,000 people may have attempted migration through the Channel Tunnel. Tragically, fatalities have occurred. People seeking a way out, a way forward, another way, are using the tunnel linking France and England. In a world challenged by climate migration, political migration, and employment migration, what kinds of channels can be safely provided to get from a troubled “here” to a better “there?”

Building the World Blog by Kathleen Lusk Brooke and Zoe G Quinn is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

May 29, 2012
by zoequinn001
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It’s All in the Timing

The Canal des Deux Mers was not a new idea by Riquet’s time, although he perfected it. The Archbishop of Toulouse headed a special commission chartered by King Henry IV (1553-1610) to study feasibility of a canal linking the Atlantic and the Mediterranean. Henry IV was following a line of similar visionaries. Even Charlemagne wanted to build the canal. There is evidence of ancient Roman emperors trying to engineer the route. Charlemagne, to be fair, didn’t have the technology. But Riquet was able to conquer a rocky patch near Beziers by blasting a tunnel – measuring 157 meters (515 feet) long, 6.7 meters (22 feet) wide and 8 meters (27 feet) high – with black powder. It was one of the earliest uses of explosives in subterranean construction.

The tunnel as it exists today, from canaldumidi.org

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Building the World Blog by Kathleen Lusk Brooke and Zoe G Quinn is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

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