[jonstewart]

Have you ever heard of induced demand? More roads and bridges are not the answer, especially since the associated capital costs could go a long ways towards fixing Metro and thereby provide greater utility.

Northern Virginia has some of the absolute dumbest land use policies and traffic planning of anywhere in the nation. It's reaping what it's sown with traffic congestion. This is a big step in the right direction. (I live in DC, because I can't stand Virginia.)

[AnthonyMouse]

> Have you ever heard of induced demand?

That is not what happens. The effect they're measuring is that a road gets congested, the congestion suppresses the natural demand, and if you expand the road to reduce the congestion then more of the natural demand comes back and there is still more congestion than you expected.

But the same applies to any of the alternatives. If you build more housing in the metro area then there are less cars, which reduces congestion some, but not very much because as soon as there is less congestion for any reason, more people drive.

The only way to eliminate the congestion is to satisfy the entire demand. You can do that by expanding the roads, you can do that by making it less expensive to actually live in the city, but it's often more effective to do both.

A much worse choice is to suppress the natural demand with tolls, which will certainly reduce congestion, but will also screw up your city even worse because people are severely punished for living in the suburbs even though there still isn't enough urban housing. So urban housing prices go up, commuting costs go up, and everyone in the city becomes poorer (except the landlords and toll companies).

[jonstewart]

DC's been on a building spree and rents have stabilized, maybe even decreased a bit. In the greater Metro area, there are four fundamental problems: 1) new housing and jobs are placed too far away from Metro; 2) Metro is severely under-capitalized due to a lack of a dedicated funding source, so they can't undertake the projects they need to restore the level of service that was unsustainably enjoyed in the late 90s/early 00s; 3) we haven't prioritized bus service with BRT, transit ways, dedicated bus lanes, etc., to serve as a middle tier between cars and Metro; 4) DC lacks autonomy from Congress and Congress has explicitly forbade DC from enacting anything that resembles a commuter tax. If we tolled every car coming into DC (NYC and SF have tolls on their bridges and tunnels), that could be a nice funding stream for mass transit projects; but we can't simply because of Congress.

#1 is probably the overall most important factor. See https://ggwash.org/view/65596/the-best-way-improve-transport..., and check out the link to the actual study report.

There's also an exacerbating problem, especially within DC's boundaries, that the rise of Uber and Lyft at the same time Metro has taken a nose-dive means an individual can be better off using ride-hailing instead of using mass transit, but it puts more cars on the street and makes street-level congestion horrible. Hopefully DC's DDOT will start carving out dedicated bus lanes so that many DC residents are assured better commutes through bus than through ride-hailing.

[AnthonyMouse]

> DC's been on a building spree and rents have stabilized, maybe even decreased a bit.

You can obviously offset something that raises rents by doing something that lowers rents, but then you're only depriving yourself of the benefits you would have had from actually lowering rents (or lowering them more) instead of having the benefit canceled out. And it still screws over anyone who still can't afford to live in the city.

> new housing and jobs are placed too far away from Metro

It's probably also that new housing and jobs are placed too far away from each other.

> dedicated bus lanes

Bus lanes are crazy. It's impossible for them to cause congestion relief because the instant they actually did the bus lane would no longer confer any advantage to the bus and any incentive it provided not to drive would evaporate. So it's logically impossible for them to actually solve the problem, but they can easily make it worse by wasting road capacity when the reason people don't take the bus isn't just congestion, e.g. if the bus doesn't go where they need it to.

> If we tolled every car coming into DC (NYC and SF have tolls on their bridges and tunnels), that could be a nice funding stream for mass transit projects; but we can't simply because of Congress.

Tolls are popular with some cities because it's effectively taxation without representation. The city gets to collect money from people who live in neighboring cities and states, who don't get a vote on whether there should be a toll there. This is not commendable behavior.

And there is no magic. One way or another the citizens have to pay for the infrastructure. It's not like tolls can cost them less money than to pay for it with normal taxes. For most people it will cost them more, because tolls are incredibly regressive. Even more regressive than flat taxes. And on top of that you have to pay the overhead cost to collect the tolls.

Build housing and eliminate rules that prevent it from being built, and build infrastructure and pay for it with normal taxes. Don't make driving worse, make the alternatives better.

[xtreme]

I never understood this argument against more roads/bridges. Even if there is no improvement in latency (travel times), isn't the increase in throughput (number of people traveling) and the associated economic benefit worth it?

[jonstewart]

In addition to the counterintuitive traffic congestion stuff, you also have to consider cost. Bridges ain't cheap. Metro isn't either... but you could make a lot of improvements to Metro for the price of a bridge.

The 7000 series has fortunately been a godsend for Metro. Now it just needs a miracle for each of: power supply, rail insulators, water leaks, automated control, and the union contract/pension.

[usaar333]

Not necessarily

https://en.m.wikipedia.org/wiki/Braess%27s_paradox

[philwelch]

At the expense of turning cities into 1970’s-era concrete hellscapes where you need to drive to get anywhere.