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Comment by vondur | Hacker News Reader

Ha, this is California and it cost 92 million US dollars

More interestingly is the timeline. Broke ground in 2022, finished in 2025, and likely operational before the end of the year.

Now sure, it likely took some years in the planning as well, but it shows that infrastructure can be built in reasonable time lines when politics and nimbyism don't get in the way.

And this isn't a simple bit of construction- it spans a serious bit of active highway.

> shows that infrastructure can be built in reasonable time lines

This bridge for deer took 3 times longer to build than the Empire State Building.

A bridge for deer isn't any easier to build than a bridge for pedestrians, even if you don't care about deer being on a bridge that collapses there's a highway underneath. Cars would be crushed and traffic disrupted. So we're just talking about a bridge. It's built to the same standard as any other bridge. (Also it's more like a bridge for mountain lions but whatever.)

If the Empire State Building had been built across a highway, and had to schedule construction around avoiding disruptions to traffic, than it would've taken three years too.

Bridges for pedestrians are far lighter construction than bridges for cars and trucks.

Pedestrians are also far lighter than cars and trucks, and slightly lighter than deers.

Pedestrians also happen to be much denser than cars though, since cars are mostly air, while humans are mostly water, which can lead to some interesting situations (and Wikipedia articles)

My dad worked for a while as an accident investigator for the Air Force. One time there was a crash where a pilot deliberately flew into a cliff at top speed.

The only evidence they ever found of his body was a finger joint. My dad said the body just turns into spray at those speeds.

Typical pedestrian bridges aren't 150 feet wide, though. Nor do most have grass growing on them (at least, not intentionally). This is, in fact, a fairly unusual infrastructure project.

I'd imagine that once you're 150 ft wide the potential for several vehicles driving across or parking has to be considered.

Quite possibly. Although I'm not sure that's even significant compared to the increase in weight when it rains, waterlogging the soil on the bridge.

I'd make the bridge bed porous.

Easy to make it impassable for vehicles.

5 people died constructing the Empire State Building.

0 people died constructing this bridge.

I guess if you think working class people's lives aren't important then the human cost doesn't matter to you, but for non-sociopaths it does matter.

But in general, workers on road projects are killed every year. Yet we still build roads.

Plus the empire state building doesn't have to worry as much about crushing people to death in a 7.0 earthquake

We went faster when human life had less value. It has more value now, both in labor time (and therefore cost) and harm potential/reduction, so it takes more time and money than it used to. Similar story about disposable workers when the Hoover Dam was built.

We should expect this math to continue as prime working age cohort shrinks over the next century due to structural demographics.

Certainly this is a factor; is there a reason to think it is a significant one?

For deer? It's much more for the endangered wild life like mountain lions. I loved in so cal and we had multiple passes like this and it was incredibly helpful in maintaining the mountain lion population

However you slice it, the time it took for this project to complete is absurd. Project started in 2002, it took 20 years to plan this, then it took 3 years to build this low-tech bridge.

Even without looking at China and Middle East - in Texas they build entire highway intersection in a year.

Morbidly curious, I'd love to see a full cost and time breakdown of these projects to understand exactly where the $100M and 3 years goes. How much of that is actual people wearing boots and hardhats, and how much of it is paperwork, and waiting for this inspector to inspect that thing and then unblock this other bureaucrat to stamp onto that other paper. I'd bet the actual amount of time and money spent actually building was a single digit percentage vs. the amount of time and money spent on process and paperwork and waiting for clerks to go through their 1,000 item backlog of forms to fill out and stamp.

Bridge in earthquake zone vs an intersection is a great comparison!

This is an interesting point, but I wish the delivery wasn't so snarky. There probably are a number of issue of specialization that I wonder about now; is building bridges in an earthquake zone a solved problem at this point, or does it require additional focus that could justify some of the time and money cost. Similarly, desert ground can move a surprisingly large amount through heat and rain cycles; are similar challenges faced in places like Arizona and Texas for more ground-based infrastructure?

This bridge is not low tech. It utilizes a number of construction techniques and materials that weren't avaliable in 2002. It also spans a major freeway. It was never going to be cheap.

in Texas they build entire highway intersection in a year

California can and has rebuilt bridges in a weekend. And based on the TX Dept of Transportation website, construction on the Dallas High Five took 4 years from start to finish, after a decade of planning. And cost more than this bridge despite requiring less infrastructure to be constructed.

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