Bridges: Safe and otherwise, Issue 2, Dec 2012: Viaducto de Conchi

Built: Late19th Century
Length: 224m
Longest Span:24m
Height: 102m
Other Names: Loa Viaduct; El Viaducto de Conchi
Reason for listing: Old age combined with poor maintenance.

The Conchi Viaduct is located in Northern Chile, near the city of Calama. It was originally built for the Antafogasta - Bolivia railway, but became disused in the early 20th century when they rerouted the railway. Unfortunately, information on this impressive bridge is somewhat scarce, partly because it's fame in Chile is overshadowed by the more impressive but less scary Viaducto del Malleco.

Today there is a single lane roadway deck across the Conchie Viaduct, along with a number of pipes. The road is gated off, closing it to vehicle use. It is unclear if any of the pipes are in use, or if the bridge is completely abandoned. The level of maintenance being done is also unclear, but it does not appear to be much, if any.

Map showing location of the Conchi Viaduct.

(Map credit CIA World Fact Book)

Taking a look around we get a good feel for the area. Located in the Atacama desert, this bridge is in one of the driest deserts in the world. When it was first built the railroad only had steam locomotives, so water was even more of a problem. However, a common misunderstanding about the Atacama desert is to think that all of it gets no precipitation. While some parts of the Atacama have no recorded rainfall, large parts do in fact get rain. Sometimes it even exceeds a few centimeters a year! The mountains even get a little snow every year. As a result, there are a very few places where water can be found. But it is very scarce.

To fully appreciate this scary bridge we need to take a look at the lower deck, of which has what passes for a walkway.

Photo of The Conchi Viaducti, lower deck.

People clearly could cross this walkway. But before doing so they should note that it is poorly maintained, has some holes in it, and is is a very long way down. There is also a high risk of improperly secured planks, of which would move when stepped on. Sticking with the upper deck is a safer option.

After taking another look at the Conchi Viaduct, we will compare it to a Not At All Scary Bridge (NAASB).

Here is a nice looking bridge, and it is about as not-scary as a good sized bridge can get.

While admiring the curves of the NAASB, take a moment to consider its history. When the Conchi Viaduct was built in 1888, this was a toll ferry. Since then this is the third bridge to stand on the site. Come 2100 which bridges will still stand?

That's it for now. The reader is left to consider what scary bridge will be found next and why there is a good sized lake in the middle of the Atacama.

Last Updated: Mar 2014; Minor corrections & formatting fixes

The Conchi Viaduct

Scary Bridges · Issue 2