Forested Overpasses Allow Animals to Cross Safely Over Highways • Hacker News Board

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#51

Post by melling » Fri, Sep 25, 2015, 9:42 PM UTC

tcdent wrote: post #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 i…

Someone proposes a cost effective solution then someone else feels the need to take the solution to a limit. "Just put everything underground"

How about we try the cheaper solution first then talk about burying highways at a later date?

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#52

Post by benihana » Fri, Sep 25, 2015, 9:56 PM UTC

tcdent wrote: post #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 i…

>build all major roads in tunnels, and bring the recovered surface area back to it's original state for all to enjoy.

How deeply have you thought this idea through? What happens in places like Florida where the water table is so high you can't dig deeper than a few feet? How do you manage entrances and exits, how do you make sure there's breathable air down there in case people have to get out of their cars? How do you vent poisonous gases? How do you keep the precious animals you're trying to save from getting in there and getting trapped or run over? What about emergency access? You can't open a gate on a service road and suddenly be underground.

Those are just a couple of simple practical considerations that don't even factor in cost, which would be prohibitive.

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#53

Post by afarrell » Fri, Sep 25, 2015, 10:03 PM UTC

jamespitts wrote: post #10

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.

They kinda did this in Boston and it was expensive but fantastic.

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#54

Post by scott_s » Fri, Sep 25, 2015, 10:04 PM UTC

Retric wrote: post #32

jamespitts wrote: post #10

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.

Baltimore has an interesting network of outdoor walkways above street level connecting the inner harbor, convention center, and a few nearby buildings. I have long thought a city could do this for a much larger part of downtown at reasonable expense. Crystal city VA on the other hand has an underground mall covering well over a mile including a subway stop. The upside is weather becomes irrelevant, but the downside i…

Minneapolis does this: https://en.wikipedia.org/wiki/Minneapolis_Skyway_System

I was there in early fall, when it wasn't cold enough to make a difference, but we went through them for the novelty. Every time we emerged on the street, we were terribly disoriented.

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#55

Post by tcdent » Fri, Sep 25, 2015, 10:29 PM UTC

benihana wrote: post #52

tcdent wrote: post #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 i…

>build all major roads in tunnels, and bring the recovered surface area back to it's original state for all to enjoy. How deeply have you thought this idea through? What happens in places like Florida where the water table is so high you can't dig deeper than a few feet? How do you manage entrances and exits, how do you make sure there's breathable air down there in case people have to get out of their cars? How do y…

These are all problems that have been solved. There are many existing solutions for elevating people...

Are you suggesting that it is impossible to build a subway where groundwater exists? [1]

All sizable tunnels have ventilation. While we still run combustion engines, we could capture unburnt fuel vapor and use it. With electric vehicles the capacities needed are much lower.

> How do you keep the precious animals you're trying to save from getting in there and getting trapped or run over?

Animals will not have a reason to enter if there is not something to be gained. Currently, they are provoked by the need for water and food, which justify the dangerous risks they must take. Living every day as a gatherer with no guaranteed access to water is not something I'm not convinced you have the empathy to understand.

[1] http://scienceline.org/2010/02/what-would-you-do-with-eight-...

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#56

Post by blux » Fri, Sep 25, 2015, 10:36 PM UTC

We already have a lot of those in the Netherlands. This is a step in the right direction. Ideally, I would like to see highways surfacing here and there between forests instead of the other way around. I think this is the direction we are heading in though. We are now at a point in time where we can afford to invest in beautifying our environment instead of just manipulating it to suit our needs.

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#57

Post by dalke » Fri, Sep 25, 2015, 11:14 PM UTC

benihana wrote: post #52

tcdent wrote: post #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 i…

>build all major roads in tunnels, and bring the recovered surface area back to it's original state for all to enjoy. How deeply have you thought this idea through? What happens in places like Florida where the water table is so high you can't dig deeper than a few feet? How do you manage entrances and exits, how do you make sure there's breathable air down there in case people have to get out of their cars? How do y…

Your points are all valid. I want to add that the equivalent for a tunnel for parts of Florida is an elevated roadway. When State Road 84 was built through the Everglades, it blocked water flow and generally had poor environmental planning. The upgrade to I-75 included 'bridges and culverts designed to let water and wildlife pass underneath' (quoting Wikipedia).

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#58

Post by rgovind » Fri, Sep 25, 2015, 11:15 PM UTC

Mikeb85 wrote: post #11

I still remember when these overpasses were first built, there was a lot of scepticism and animals were initially wary to cross. However it's nice to see how much of a success it's become. Not too long ago I took the wife's family to Banff, we checked out one of the information buildings, they showed a time-lapse video of the various animals that cross (pretty much every type of large mammal in the park). Was very in…

If I am a meat eating animal like a wolf or something, Do I just have to wait at this bridge to hunt?

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#59

Post by dalke » Fri, Sep 25, 2015, 11:31 PM UTC

tcdent wrote: post #55

benihana wrote: post #52

Earlier quoted context omitted.

>build all major roads in tunnels, and bring the recovered surface area back to it's original state for all to enjoy. How deeply have you thought this idea through? What happens in places like Florida where the water table is so high you can't dig deeper than a few feet? How do you manage entrances and exits, how do you make sure there's breathable air down there in case people have to get out of their cars? How do y…

These are all problems that have been solved. There are many existing solutions for elevating people... Are you suggesting that it is impossible to build a subway where groundwater exists? [1] All sizable tunnels have ventilation. While we still run combustion engines, we could capture unburnt fuel vapor and use it. With electric vehicles the capacities needed are much lower. > How do you keep the precious animals yo…

"Are you suggesting that it is impossible to ..."

No, merely expensive. The Gotthard Base Tunnel is US$10.3 billion for "a route length of 57 km (35.4 mi) and a total of 151.84 km (94.3 mi) of tunnels, shafts and passages". (Quoting Wikipedia.) That's $290 million/mile.

The Fehmarn Belt Fixed Link is estimate to cost €4.7 billion for 17.6 km of immersed tunnel, or $480 million/mile.

The boondoggle that is the Alaskan Way Viaduct replacement tunnel is in the same range.

By comparison, a rural interstate road costs about $5 million/mile, or a factor of 50 cheaper.

Re: Forested Overpasses Allow Animals to Cross Safely Over Highways

#60

Post by Cthulhu_ » Fri, Sep 25, 2015, 11:31 PM UTC

davedx wrote: post #28

I took our kids to find one of these ("ecoducts" in the Netherlands) about a half hour drive from where we live. It was fantastic: no sign of humans anywhere except the speeding traffic under us on the motorway; just lots of animal footprints, and a single surveillance camera that I imagine is used to check out the furry users of the bridge rather than for any "security" related tasks. The kids loved it :) They found…

I bet that's the same experience some people have with an aqueduct - https://upload.wikimedia.org/wikipedia/commons/d/d8/Ie-akwad...