
Why the Amazon River Can't Be Crossed by Bridge (2018) - apsec112
https://www.cntraveler.com/story/why-the-amazon-river-cant-be-crossed-by-bridge
======
tiagobraw
When I was young (I think I was 18 years old), me and my dad traveled across
all the length of Amazon river (from Belém to Manaus) in a crowded boat
sleeping on hammocks, it was a 6 days trip.
[https://goo.gl/maps/BFkCPx1HR1n](https://goo.gl/maps/BFkCPx1HR1n)

In some places the river was really narrow and almost could be crossed by
swimming, but there where times that I couldn't see any of the two margins
because of its enormous width.

Is was a really great experience, got to talk to indigenous people, saw a lot
of botos cor-de-rosa
([https://en.wikipedia.org/wiki/Amazon_river_dolphin](https://en.wikipedia.org/wiki/Amazon_river_dolphin))
and got to eat amazing local dishes.

~~~
tdfx
How did you set this up? Doesn't seem like the kind of tourist package you'd
see on TripAdvisor.

~~~
senorjazz
The river is / was the main highway, not sure about now with more year round
roads etc, but when I was last in the area, long time ago now mind,you would
just turn up and get on the boat. It wasn't comfortable, wasn't all that
enjoyable after (x) hours and (y) days.

Lots of being bored, interspersed with the odd enjoyable / memorable moments.
Which looking back on, is all you remember :)

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arjunvpaul
Always happy when bridges get discussed here. Having built (a couple of)
bridges across the Mississippi, i can attest that it is possible to build a
bridge across the Amazon. This headline is appears to be click bait

A river rising 30 feet is no big deal. I think the Amazon rises more than that
actually. The Mississippi very often rises to 40 feet.More in some years.
Here's a video of a 300yr flood hitting in the middle of bridge construction -
[https://www.youtube.com/watch?v=Orj6B46PJbY](https://www.youtube.com/watch?v=Orj6B46PJbY)
(skip and pause at 0:17)

~~~
Brendinooo
>the river rises thirty feet, and crossings that were once three miles wide
can balloon to thirty miles in a matter of weeks.

My impression wasn't so much that it was the 30 feet rise, but the fact that
it added 27 miles to the width of the river. Does the Mississippi do that as
well? (The Ohio/Monongahela/Allegheny are my baseline, so it's harder to
comprehend rivers that do stuff like this!)

~~~
arjunvpaul
The Mississippi would, but doesn't to that scale today, because the Army Core
has leveed/dyked in most places.

You can see in the pictures here
[http://bit.ly/2u7f2ta](http://bit.ly/2u7f2ta) that there is a lot of "marsh"
beyond where the river bank ends. You just have to extend the roadway as far
as you like. You can see how the bridge extends beyond the river on both
sides.

This particular bridge for example has 18 miles of approach roadways. Only
about 1600 feet of that, spans the Mississippi.

In short, if flooding adds 27 miles or 270 miles of width, the engineering is
pretty much the same. You just have to know, where to start and finish :-)

~~~
Brendinooo
Very interesting! Thanks for this.

------
renholder
> _For most of its length, the Amazon isn 't anywhere close to too wide to
> bridge—in the dry season. But during the rainy season, the river rises
> thirty feet, and crossings that were once three miles wide can balloon to
> thirty miles in a matter of weeks. The soft sediment that makes up the river
> bank is constantly eroding, and the river is often full of debris, including
> floating vegetation islands called matupás, which can measure up to 10
> square acres. It's a civil engineer's worst nightmare._

Isn't this the predominance of what the ACE (Army Corps of Engineers) deals
with when it comes to the Mississippi River[0]?

[0] -
[https://www.tulane.edu/~bfleury/envirobio/enviroweb/FloodCon...](https://www.tulane.edu/~bfleury/envirobio/enviroweb/FloodControl.htm)

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nisse72
_up to 10 square acres_

I cannot fathom this 4 dimensional unit!

~~~
benj111
That's because a fathom is a unit of length (or depth) so 4 in to 1 obviously
isn't going to work.

~~~
btown
What does work have to do with any of this? Sure, the water acts on the
floating vegetation in the direction of displacement, but without a measure of
the weight of the islands, it's somewhat meaningless.

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justinator
See also, the Darién Gap:

[https://en.wikipedia.org/wiki/Dari%C3%A9n_Gap](https://en.wikipedia.org/wiki/Dari%C3%A9n_Gap)

First crossed overland by bicycle (or I guess _with_ bicycle) by Ian Hibell in
1973:

[https://www.youtube.com/watch?v=3ylhWPCekdM](https://www.youtube.com/watch?v=3ylhWPCekdM)

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theNJR
I was hoping for this to be a lot longer and include pictures.

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minikites
The Amazon pushes a tremendous amount of fresh water into the ocean:

>The river pushes a vast plume of fresh water into the ocean. The plume is
about 400 kilometres (250 mi) long and between 100 and 200 kilometres (62 and
124 mi) wide. For centuries ships have reported fresh water near the Amazon's
mouth yet well out of sight of land in what otherwise seemed to be the open
ocean.

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brianbreslin
There are several huge highway projects in the area that are linked directly
to deforestation and other concerns as well.

[https://en.wikipedia.org/wiki/Interoceanic_Highway](https://en.wikipedia.org/wiki/Interoceanic_Highway)

------
trhway
like some countries/societies jumped straight into cell/smartphones by-passing
the landline stage, i think such areas like Amazon should and would go
straight the way of "flying car" (all those multi-copters popping around e.g.
[https://www.youtube.com/watch?v=FNxoHqZGYa0](https://www.youtube.com/watch?v=FNxoHqZGYa0)
\- just add ICE/hybrid generator for range and tilt-able ducts for safety).
Much less environmental damage, cheaper than whole road infrastructure and
much faster to cover those distances.

~~~
burfog
Skipping the landline stage means skipping the need to stabilize the situation
on the ground, particularly involving crime. There is a lot to be said for the
side-effects of landlines, other utilities, a postal service, roads, and so
on. Widely exposed public assets need protection, and so they get it, and thus
the place is becalmed.

Cell towers are tiny little spots that can be fortified without much concern
for the surrounding situation. They don't provide an incentive to care about
any troubles in the area.

~~~
magduf
They have landlines and postal service in Baltimore, yet the murder rate is
horrific.

------
mc32
If they did build one, it’s quite likely, as feared by some, to result in
increased human activity in the vecinity of the basin. That’s to say, expect
some clearing of parts of the forest.

------
mirimir
Near its headwaters, the Amazon is not so wide, and runs through ~narrow
canyons. I wouldn't be surprised if there were footbridges. I don't find
images of any, though. But there is this:
[https://planetsave.com/2010/07/23/amazon-river-10-friday-
pho...](https://planetsave.com/2010/07/23/amazon-river-10-friday-
photos/amazon-river-headwaters/)

~~~
mcv
That article reflects similar lessons learned in Netherland: rivers need space
to expand. We've got a long and treasured history turning lakes and seas into
land (polder), but recently, and somewhat controversially, we've started
abandoning a few polders in order to give floods a better place to go than
population centers.

------
ngcc_hk
Shouldn’t ... but can’t? Always can.

~~~
rflrob
But the title “if you want to cross the Amazon by bridge, you’ll first need to
build one” isn’t nearly as snappy.

------
nkoren
Tracing the Amazon from its headwaters...

Here's a bridge:
[https://www.google.com/maps/@-15.2762023,-71.6326301,334m/da...](https://www.google.com/maps/@-15.2762023,-71.6326301,334m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-15.1768982,-71.6372406,233m/da...](https://www.google.com/maps/@-15.1768982,-71.6372406,233m/data=!3m1!1e3)

Here's a couple of bridges:
[https://www.google.com/maps/@-14.8748328,-71.5192037,233m/da...](https://www.google.com/maps/@-14.8748328,-71.5192037,233m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-14.8073581,-71.4882189,863m/da...](https://www.google.com/maps/@-14.8073581,-71.4882189,863m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-14.7501513,-71.4792706,326m/da...](https://www.google.com/maps/@-14.7501513,-71.4792706,326m/data=!3m1!1e3)

Here's a bridge (with some spectacular ancient ruins just north of it, wow!):
[https://www.google.com/maps/@-14.7317275,-71.4653133,372m/da...](https://www.google.com/maps/@-14.7317275,-71.4653133,372m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-14.6865893,-71.4459353,271m/da...](https://www.google.com/maps/@-14.6865893,-71.4459353,271m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-14.6503598,-71.4346162,335m/da...](https://www.google.com/maps/@-14.6503598,-71.4346162,335m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-14.6068402,-71.4539496,370m/da...](https://www.google.com/maps/@-14.6068402,-71.4539496,370m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-14.5375724,-71.4662274,376m/da...](https://www.google.com/maps/@-14.5375724,-71.4662274,376m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-14.4966649,-71.4655178,619m/da...](https://www.google.com/maps/@-14.4966649,-71.4655178,619m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-14.4821393,-71.4651525,932m/da...](https://www.google.com/maps/@-14.4821393,-71.4651525,932m/data=!3m1!1e3)

Here's a bridge, fascinating remnants of high-intensity agriculture in the
area. Clearly supported a much larger population during pre-Columbian times:
[https://www.google.com/maps/@-14.4041017,-71.4689323,467m/da...](https://www.google.com/maps/@-14.4041017,-71.4689323,467m/data=!3m1!1e3)

Here's a couple of bridges, including a famous rope bridge:
[https://www.google.com/maps/@-14.3821426,-71.4849719,637m/da...](https://www.google.com/maps/@-14.3821426,-71.4849719,637m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-14.2970991,-71.5081793,491m/da...](https://www.google.com/maps/@-14.2970991,-71.5081793,491m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-14.2257273,-71.5213399,828m/da...](https://www.google.com/maps/@-14.2257273,-71.5213399,828m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-14.1689771,-71.5576715,754m/da...](https://www.google.com/maps/@-14.1689771,-71.5576715,754m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-14.1260513,-71.6607489,453m/da...](https://www.google.com/maps/@-14.1260513,-71.6607489,453m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-13.9539948,-71.7544463,863m/da...](https://www.google.com/maps/@-13.9539948,-71.7544463,863m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-13.932637,-71.7777958,853m/dat...](https://www.google.com/maps/@-13.932637,-71.7777958,853m/data=!3m1!1e3)

Here's a bridge, with Streetview! The former bridge looks pretty dodgy:
[https://www.google.com/maps/@-13.8145316,-71.8335396,3a,60y,...](https://www.google.com/maps/@-13.8145316,-71.8335396,3a,60y,18.5h,84t/data=!3m6!1e1!3m4!1sv843XwPsUXbIPJanyqSdYw!2e0!7i13312!8i6656)

Here's a bridge:
[https://www.google.com/maps/@-13.8304518,-71.942204,375m/dat...](https://www.google.com/maps/@-13.8304518,-71.942204,375m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-13.8211571,-71.9706923,320m/da...](https://www.google.com/maps/@-13.8211571,-71.9706923,320m/data=!3m1!1e3)

Here's a bridge, with an ex-bridge just upstream:
[https://www.google.com/maps/@-13.7749211,-72.0847456,168m/da...](https://www.google.com/maps/@-13.7749211,-72.0847456,168m/data=!3m1!1e3)

I don't understand why there's a bridge here, but there is:
[https://www.google.com/maps/@-13.77597,-72.0966336,194m/data...](https://www.google.com/maps/@-13.77597,-72.0966336,194m/data=!3m1!1e3)

Here's a pre-bridge:
[https://www.google.com/maps/@-13.6966954,-72.2455627,451m/da...](https://www.google.com/maps/@-13.6966954,-72.2455627,451m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-13.6901983,-72.3356296,515m/da...](https://www.google.com/maps/@-13.6901983,-72.3356296,515m/data=!3m1!1e3)

Here's a bridge, with more streetview:
[https://www.google.com/maps/@-13.5627059,-72.5751752,3a,60y,...](https://www.google.com/maps/@-13.5627059,-72.5751752,3a,60y,71.84h,91.03t/data=!3m6!1e1!3m4!1sgeFdQ8Yatbwq3h3HcgQu_w!2e0!7i13312!8i6656)

Here's a bridge:
[https://www.google.com/maps/@-13.4215974,-72.852207,437m/dat...](https://www.google.com/maps/@-13.4215974,-72.852207,437m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-13.4163366,-72.8835264,419m/da...](https://www.google.com/maps/@-13.4163366,-72.8835264,419m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-13.4450156,-73.1816146,699m/da...](https://www.google.com/maps/@-13.4450156,-73.1816146,699m/data=!3m1!1e3)

Here's a bridge:
[https://www.google.com/maps/@-13.3103693,-73.329247,409m/dat...](https://www.google.com/maps/@-13.3103693,-73.329247,409m/data=!3m1!1e3)

Now we're starting to get into lowlands jungle, but still, here's a bridge:
[https://www.google.com/maps/@-12.6227864,-73.7872767,846m/da...](https://www.google.com/maps/@-12.6227864,-73.7872767,846m/data=!3m1!1e3)

...And I believe that is indeed the last one.

~~~
arcticfox
At least in Brazil, it's not considered truly the Amazon until the Rio
Solimões and Rio Negro combine, which makes sense, as they are the two
enormous tributaries that combine to form the mega-river. You're splitting
hairs here, of course the tributaries have bridges across them.

That said I do agree that the whole premise of the article is pretty dumb,
considering the Brazilians fairly easily (minus graft) built a bridge across
the Rio Negro right before it becomes the Amazon. If they wanted to, they
could do it after as well.

~~~
alexhutcheson
Interesting! Brazil calls it the Solimões, but most of the rest of the world
just calls it the Amazon:
[https://en.wikipedia.org/wiki/Solim%C3%B5es_River](https://en.wikipedia.org/wiki/Solim%C3%B5es_River)

On the US version of Google Maps, the Amazon starts where the Marañón and
Ucayali rivers combine in Peru:
[https://goo.gl/maps/ia7gCLD1k5M2](https://goo.gl/maps/ia7gCLD1k5M2)

------
pwaivers
The _matupás_ mentioned in the article are also really interesting:
[https://www.atlasobscura.com/articles/the-science-and-
legend...](https://www.atlasobscura.com/articles/the-science-and-legend-of-
the-amazon-s-floating-forest-islands)

------
cpeterso
Too wide

~~~
taneq
Too wide, width too variable with season, insufficient roads to justify the
effort and expense.

