| > 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). |
#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.