Civil engineering tends to be massive in scale by its very nature, but some civil engineering projects are so impressive that they stretch the imagination of what is possible.

Difficult at times to truly comprehend


Spectacular feats of engineering are always impressive, but when it comes to civil engineering marvels, the sheer scale of the feat can be difficult at times to truly comprehend.

Some projects are singular, elegant, and record-breaking efforts, as is the case of the Millau Viaduct in Millau, France, the tallest bridge in the world.

Millau Viaduct, Millau, France. Source: Richard Leeming/Flickr

Others were the accumulation of several smaller projects that together transformed an entire region the way the Tennessee Valley Authority did in the Tennessee Valley in the United States, building a dozen hydroelectric dams and completely electrifying several US states at the height of the Great Depression.

Whatever the project, the scale of these civil engineering marvels put them at the forefront of what can be achieved through human ingenuity.

The Millau Viaduct in the south of France, reaching 343 metres tall at its highest point, is taller than the Eiffel Tower by several metres, and supports a roadway that passes over the Tarn river at a height of 270 metres.

In an interesting twist, the Millau Viaduct was built by the construction company Eiffage, the same company that built the Eiffel tower.

Elegance of the design


While its height makes it impressive on its own, the elegance of the design in its valley setting makes the viaduct a breathtaking work of civil engineering.

MOSE Venice Tide Barrier, Venice, Italy. Source: Chris 73/Wikimedia Commons

Venice, Italy, is located in the middle of a lagoon, so it might not be all that surprising that it has long known how to deal with water.

That said, nature is still a force to be reckoned with even for the Venetians, and the Adriatic Sea can still produce high tides that can flood the plazas and 'street-level' storefronts of one of the most popular tourist destinations on the planet.

These events, known as acqua alta high tides, have become more frequent, prompting local authorities to develop new systems for managing this large influx of water by isolating the lagoon from the Adriatic through a series of mobile gates and other efforts to hold back a high tide of nearly 10 feet.

Palm Islands, Dubai, United Arab Emirates. Source: Skatebiker/Wikimedia Commons

Land reclamation isn't a new idea, and regaining valuable land from the sea goes back centuries, but the Palm Islands of Dubai, United Arab Emirates, stand out more than most.

Shaped like a palm tree in the middle of the sea, the Palm Islands –technically Palm Jumeirah and Palm Jebel Ali – are dredged sand shaped into the form of a palm tree topped by a nearly seven-mile-long crescent.

It is only the most famous of several artistic land reclamation projects in the UAE and is home to several luxury resorts.

The Hoover Dam (main photo) is arguably one of the most famous in the world. Built during the Great Depression – from 1933 to 1936 – the Hoover Dam sits on the Colorado River, between the states of Arizona and Nevada, about 30 miles (50km) south of Las Vegas, Nevada.

The site had been scouted as a dam site a couple of decades earlier and was approved in 1928 by the US Congress.

The largest-ever dam construction when it was built, the arch-gravity dam used several techniques in dam construction that were at the time untested.

Required thousands of workers


The construction required thousands of workers to build, more than 100 of whom died during construction. The result is a modern marvel of civil engineering that impounds the largest reservoir of water by volume in the United States, Lake Mead, which supplies drinking and irrigation water for much of the American southwest.

Tennessee Valley Authority, Tennessee Valley, United States. Source: Carol Highsmith/Library of Congress

Speaking of dams, around the same time as the construction of the Hoover Dam, the US government was funding another major effort over a thousand miles away in the Tennessee Valley, located in the Appalachia region of the eastern United States.

This area, particularly hard hit by the Great Depression was also largely rural and poor, and largely lacked any form of electrification.

In 1933, the US Congress created the Tennessee Valley Authority (TVA) as a federally owned corporation with Eminent Domain authority to begin economic development in the region, with a particular focus on infrastructure projects.

Over the next 20 years, the TVA would build more than a dozen dams in the region, including 11 concurrent dam projects at one time, to bring electric power to a region that otherwise might have been left behind for decades.

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The TVA wasn't without controversy, however. More than 15,000 families were displaced as a result of the dam constructions, engendering considerable resentment by many that hasn't been forgotten nearly 100 years later.

This article was written by John Loeffler and is reproduced with kind permission from InterestingEngineering.com. Find the link to the original article here.