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Forested Overpasses Allow Animals to Cross Safely Over Highways

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Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#42

People in cities need something similar. It would be hugely beneficial to have a bustling business district lined up on the left and right side of urban freeway crossings.

Several cities in the colder parts of the US and Canada have extensive networks of enclosed pedestrian bridges, such that you could cross downtown without ever going outside.

For example, see Minneapolis https://en.wikipedia.org/wiki/Minneapolis_Skyway_System

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#43

We have these in Montana, at least on the Flathead Indian Reservation where I lived until recently. It's a great idea and really helps preventable deaths to elk herds. Here's a picture (note: the language on that sign is Salish) http://www.sunnyskyz.com/uploads/2015/01/mpr6e-animal-crossi...

Cool. I cannot help but think it would be majorly uncool if the elk decide to fight on it and come down on my car. I passed within 3 ft of an elk on a slippery road during a blizzard in the 90's. Those things are scary dangerous.

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#45
post #14

Earlier quoted context omitted.

This is the entire point of projects to put freeways in tunnels.

I run into this in Barcelona: https://goo.gl/maps/4fQfpa7CoPH2

On the other hand, look at something like the Cross Bronx Expressway.

https://goo.gl/maps/RfeVWuS2X5J2

A neighborhood torn apart 60 years ago....is still torn apart.

Do you know if the residential/commercial developments around the tunnel were built at the same time as the roadway? New transportation infrastructure is much easier to integrate into new urban developments, but it would be nice to see something done in existing communities.

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#46
You see a similar idea quite often on the north shore of the St. Lawrence in Quebec. Usually they are underpasses, though, and usually combined with a 8-10', very sturdy fence system to funnel the animals into these crossing points and prevent them crossing the highway. Honestly, I think they are more motivated by preventing human fatalities from moose-vehicle collisions, which are exceptionally deadly, primarily, with the ecological concerns secondary.

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#47

Wondering how/if they ensure the animals use the bridge rather cross the highway? Fencing? Natural selection (Animals who prefer bridges more likely to pass their genes down)?

the ones i have seen have fencing funnels to them, there are gates for humans to cross, but the fence runs from one overpass to the next. the animals have no choice but to use the overpass.

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#49
I have a vision, inspired by this problem, where every major highway is a "forested overpass".

Instead of bisecting the top layer with roads and fences, build all major roads in tunnels, and bring the recovered surface area back to it's original state for all to enjoy.

Availability of suitable habitat for native species is only getting worse. If we blindly follow the path we are on, confrontation and compromise are inevitable, and humans don't typically lose this battle.

It's no surprise city centers and golf courses occupy the most desirable land (valleys along waterways). Southern California especially has a habit of teraforming natural waterways and fencing them to prevent access; it's amazing any water is still available to wild animals.

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#50
post #3

I'm curious how they are engineering these overpasses to not be slowly torn apart by tree roots, if they even consider that at all.

From that viewpoint, the difference between this and a tunnel is minute.

They may be built the other way around, but you _can_ see these things as artificial hills with a tunnel dug through them. The effect of tree growth on their longevity will be similar.

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